What causes an engine to hesitate when accelerating?

What causes an engine to hesitate when accelerating?

Probable Causes: An engine that hesitates, stumbles or misfires when accelerating or when it is under load, is an engine that is either sucking too much air, not getting enough fuel, or misfiring.

Why does my Toyota Corolla hesitate during acceleration?

When a vehicle is hesitating during acceleration, it should be inspected by a mechanic. A vehicle with a combustion (gas or diesel) engine requires an exact mixture of fuel and air to run efficiently. If this mixture is thrown off in any way, it may result in an engine running too lean (not enough air), or too rich (not enough fuel).

Why does my Buick Lucerne hesitate when accelerating?

Dirty fuel injectors may cause the engine to run lean which will in turn, cause hesitation when accelerating. A top-rated mobile mechanic will come to your home or office to determine the reason why your vehicle is hesitating while accelerating.

What should I do if my check engine hesitates?

Protective eye wear and gloves. Begin by parking the vehicle on level ground, in park with the emergency brake on. The engine will be running in many of these tests so use necessary safety precautions. Step 1 – If a malfunction has occurred that the computer has realized, the check engine or service engine soon light will be illuminated.

Probable Causes: An engine that hesitates, stumbles or misfires when accelerating or when it is under load, is an engine that is either sucking too much air, not getting enough fuel, or misfiring.

When does your car hesitate at 45 mph?

I started getting a hesitation/bucking in my 2001 F150 SCREW 5.4L 96,000 miles. It does it most often when you are barely on the gas at 45 to 50 MPH and then you press the gas to accelerate. It hesitates for a second and then takes off.

Why does my Mercedes hesitate at a light?

2) when stopped at a light the idle is perfectly fine and steady except for these sudden dips in rpm and the engine rumbles/shakes, then back to normal. these dips are very random and don’t last more than a second. 3) when in reverse these same dips in rpm and shaky engine get more intense and more constant.

Why does my car hesitate when I open the throttle?

Engine Hesitates, Stumbles, Lacks Normal Power. The computer uses this information to determine how much fuel is needed to maintain the correct air/fuel mixture, and when extra fuel is needed if the throttle suddenly opens wide.

What should I do if my Honda engine is hesitating?

Let the engine cool. Remove the hose between the air box and the front of the throttle body. Apply a small amount of brake/carburetor cleaner to a rag, and remove the grease, dirt, or oil from around the intake valve. Check for proper throttle movement and operation. Then, re-assemble. The cost for a throttle body cleaner is $4. Figure 2.

Why does my Mitsubishi Starion have engine hesitation?

As another example, I still have a 1987 Mitsubishi Starion, which ran perfectly for 35,000 miles. Then it developed an intermittent hesitation problem- you would be cruising at 60mph, on a 400 mile trip, ease off the gas pedal, and suddenly for 1/4 second, it was as though someone had switched off the engine and then turned it back on again.

How to solve engine hesitation and stumble problems?

One way is to divide the problem into 2 parts- one which involves locating “conventional ” faults and the other deals with the computer controlled aspects. Conventional fault tracing involve basic checks such as vacuum leaks, bad fuel, wiring faults, and worn or fouled spark plugs, loose alternator belt or faulty alternator.

As another example, I still have a 1987 Mitsubishi Starion, which ran perfectly for 35,000 miles. Then it developed an intermittent hesitation problem- you would be cruising at 60mph, on a 400 mile trip, ease off the gas pedal, and suddenly for 1/4 second, it was as though someone had switched off the engine and then turned it back on again.

One way is to divide the problem into 2 parts- one which involves locating “conventional ” faults and the other deals with the computer controlled aspects. Conventional fault tracing involve basic checks such as vacuum leaks, bad fuel, wiring faults, and worn or fouled spark plugs, loose alternator belt or faulty alternator.

Dirty fuel injectors may cause the engine to run lean which will in turn, cause hesitation when accelerating.

Why does my Nissan Frontier hesitate during acceleration?

If you notice some symptoms like hesitation, you should have your vehicle inspected immediately. Mass Airflow Sensor: The mass airflow sensor measures how much air is entering the engine and relays this information to the vehicle’s computer so that the right amount of fuel can be delivered from the fuel injectors.

Why does my car hesitate when I start up a hill?

This warning may be accompanied by hesitation while accelerating, or while driving up a hill. A vehicle with a failing mass airflow sensor may also stall soon after starting. Fuel Pump:The fuel pump in most modern vehicles sits inside the fuel tank and pumps fuel up to the engine.

How did I solve the hesitation problem in my car?

I made up the lengths and took a ground from battery to Intake manifold drivers side (with a cut back to strut tower) then to passenger side manifold and onto the other strut tower, with a final one from battery negative to fire wall.

What causes a car to stumble on acceleration?

Other problems that cause acceleration stumble include vacuum leaks, low fuel pressure, a weak spark caused by low coil voltage or bad coil (s), retarded ignition timing, and contaminated gas. Look at the following with your scantool (as shown in Figure 7): throttle position, mass airflow (MAF),…

Engine Hesitates, Stumbles, Lacks Normal Power. The computer uses this information to determine how much fuel is needed to maintain the correct air/fuel mixture, and when extra fuel is needed if the throttle suddenly opens wide.

Why does my car hesitate when I change gears?

Engine hesitation is a symptom that shows, an imperfect internal combustion in your engine. Insufficient burning inside the engine, will make the vehicle hesitate when driving. This could happen during acceleration, driving downhill, or when changing gears.

Why does my car hesitate at 1500 rpm?

For a minute or so rev and hold the engine at 1500 to 2000 RPM, take a look on STFT, if the values is drop back to the more normal reading, it tell you at idle there a vacuum leaks on the engine.

Why does my car hesitate when I hit the gas?

Engine hesitation can make your vehicle seem like its; bogging down, misfiring or stumbling when you hit the gas pedal. When you step on the gas pedal; you will suddenly feel like the power has been lost in the engine. Consequently, After the engine hesitation it goes back to normal; but it may take a second or two to respond.

Dirty fuel injectors may cause the engine to run lean which will in turn, cause hesitation when accelerating.

Many times an engine can hesitate without the computer detecting a problem, if this is the case proceed to the next step. Step 2 – Poor fuel pressure can cause the engine to go “lean” when the throttle is opened. The first check is to remove the fuel filter and check the flow by trying to blow through it, the filter should flow freely.

For a minute or so rev and hold the engine at 1500 to 2000 RPM, take a look on STFT, if the values is drop back to the more normal reading, it tell you at idle there a vacuum leaks on the engine.

When a vehicle is hesitating during acceleration, it should be inspected by a mechanic. A vehicle with a combustion (gas or diesel) engine requires an exact mixture of fuel and air to run efficiently. If this mixture is thrown off in any way, it may result in an engine running too lean (not enough air), or too rich (not enough fuel).

Can a faulty fuel pump cause bad acceleration?

A faulty fuel pump will not pose problems at low speeds, but you might be left wanting when you are looking for quick acceleration. Fuel pumps usually have a long life, so checking the fuel pump on your car shouldn’t be your first action.

When does a car lose power under load?

Engine started fine, revs fine in neutral but once over 3000 revs in gear loses power under load. Has new plugs, fuel lines all seem ok, just seems it wants to kick on but splutters and drops back. Didn’t stall at all just lack of power. Can’t get it in for service until jan 2 either so anyone got any ideas that may solve my problem.

Why does my Toyota Corolla hesitate when I accelerate?

In turn, the ECM will inject a lower fuel amount for the supposedly lower airflow in order to keep the air-fuel ratio, which in turn will end up being too lean. This will produce the hesitation or stalling you are experiencing. In the worst cases, it will include engine knocking. Toyota Corolla ECM/ECU replacement.

What can cause an air intake to backfire?

A leak in the air injection system can also cause the intake to backfire, since this affects the amount of air taken in. Another possible reason is a malfunctioning fuel pump or obstructed air filter.

What to do if your car engine hesitates when you accelerate?

A good trick is if you drove your car right before doing this and the engine is still warm, just put the MAF sensor on top of the plastic cover of the engine for at least 15 minutes and the heat will dry it completely. IMPORTANT!

In turn, the ECM will inject a lower fuel amount for the supposedly lower airflow in order to keep the air-fuel ratio, which in turn will end up being too lean. This will produce the hesitation or stalling you are experiencing. In the worst cases, it will include engine knocking. Toyota Corolla ECM/ECU replacement.

Where is the intake manifold on a V6?

The manifold is located on the top of V6 and V8 engines. For inline four- or six-cylinder engines, the intake manifold is installed on the side. The manifold’s job is to provide a mixture of air and fuel to the engine’s cylinders. To do this, the intake valve opens to draw gas and air into the engine.

What can cause a backfire through the intake system?

Although there are many problems that can cause the intake system to backfire, the overall effect is the same. Since the intake valve needs to provide the engine with a proper balance of fuel and air, a backfire occurs when that balance fails.

What happens when an engine is not firing properly?

When one or more cylinder is not firing properly, the engine will become unbalanced, and this can cause heavy vibrations inside your cabin on acceleration or at idle.

How can you tell when an engine misfire is happening?

When a misfire occurs, you can feel it like a light or massive jerk coming from the engine. These misfires do often come under load from the engine, and you have the most load on the engine when you are accelerating on higher RPMs and higher gears.

What makes a GM 4.8L misfire engine stall?

P0306: Cylinder #6 Misfire. P0307: Cylinder #7 Misfire. P0308: Cylinder #8 Misfire. Really bad gas mileage. Lack of Power when you accelerate your van, pickup or SUV. Engine may start, run for a few minutes and stall.

What causes engine hesitation on a Dodge truck?

The engine hesitation on your Dodge may be created by problems in one or more components. In most cases, a bad throttle position sensor (TPS) fails to signal the engine computer about throttle operation. Other causes may be bad or worn out components in the ignition secondary system, causing the engine to accelerate poorly and even stall.

Why does my Mercedes Benz engine misfire so often?

Engine misfires are one of the most common problems we see in many Mercedes-Benz cars. To be honest, it is not because MB cars are weak in this area, but because most owners forget that spark plugs are wear items and need to be replaced at the recommended intervals.

What happens when your car’s engine is misfiring?

Whatever the cause, if your car’s engine is misfiring or surging, it will prompt error codes to appear in your OBD-II Diagnostics system. These codes can cause you to fail your local vehicle inspection, or at the very least can result in that alarming orange glow to appear on your dashboard: the Check Engine Light.

Can a phantom misfire be a check engine light?

Often called “phantom” misfires. It’s possible to find a misfire in your Ford, even if there is no check engine light. All you need is an OBDII scanner with Mode 6 function. It is a common situation. You’re driving your F150, F250, E150 van, or Expedition, etc and you can feel the engine skipping here and there.

What kind of CARB causes hesitation on acceleration?

I have an autolite 2100 that I got from Pony Carbs, put it on a 302 V8. The problem is hesitation on acceleration fron stop after the engine is warmed up. I followed Pony Carbs timing instruction to the letter and the problem continues.

What can cause hesitation on an intake manifold?

Valve Clearance: The Haynes Manual indicates that incorrect valve clearance may cause hesitation. Intake Manifold: Two considerations regarding the intake manifold: Pre-heat and air inleakage.

When does a car hesitate at a stop sign?

Car ran great except when pulling off from a dead stop under normal acceleration, like at a traffic light or stop sign in traffic. The car hesitates and stumbles, but give her a little more gas and she takes off.

Why does my Buick Lucerne engine hesitate during acceleration?

A vehicle with a combustion (gas or diesel) engine requires an exact mixture of fuel and air to run efficiently. If this mixture is thrown off in any way, it may result in an engine running too lean (not enough air), or too rich (not enough fuel).

I have an autolite 2100 that I got from Pony Carbs, put it on a 302 V8. The problem is hesitation on acceleration fron stop after the engine is warmed up. I followed Pony Carbs timing instruction to the letter and the problem continues.

Why does my car not accelerate when I press the accelerator?

If the TPS malfunctions, the engine speed cannot be controlled by the accelerator pedal and engine speed will increase or decrease without any press or depress the pedal. Report this ad #4 – Dirty or Clogged Fuel Filters A dirty or clogged fuel filteris another reason for a car not accelerating like it’s supposed to when required to do so.

What to do if your Silverado hesitates during acceleration?

Chevrolet Silverado 1500 Engine hesitates during acceleration Inspection at your home or office. Our certified mobile mechanics come to you 7 days a week between 7 AM and 9 PM. Our certified mobile mechanics can come to you now. received a Engine hesitates during acceleration Inspection.

Why does my Jeep Compass hesitate to accelerate?

An engine that is hesitating to accelerate is most likely dealing with a fuel/air mixture that is too lean. Engine’s that are running inefficiently will begin to show signs like hesitation which will only become worse over time. If you notice some symptoms like hesitation, you should have your vehicle inspected immediately.

When did the ABC system start on my Mercedes SL500?

In July of 2014, I purchased a used 2003 Mercedes SL500 with 80,000 miles on it. And within days the infamous “ABC Drive Carefully” message started appearing on the dash.

Why does my Mercedes C230 stall when I idle?

Folks I have a 1997 C230 Mercedes, This seems to be having the same problem, but when it Idles it runs rough and when driving it is stalling out but will re-start. I had the codes checked, came up with bad cam sensor. I replaced it as well the MAF.

What kind of problem does a Mercedes C230 have?

21 people found this helpful. Folks I have a 1997 C230 Mercedes, This seems to be having the same problem, but when it Idles it runs rough and when driving it is stalling out but will re-start. I had the codes checked, came up with bad cam sensor.

What are the problems with a Mercedes SL600?

Seems like a small problem, but wait until it rains. Next, air conditioning wasn’t blowing cool air and the brake warning lights were coming off all the time. There were also oil leaks, as Hoover pointed out, as well as a problem with the car’s famed hydraulic suspensions.

What to do if your car engine is bogging under acceleration?

A squirt of starter fluid at the boot while running will tell you. If it revs you have a vacuum leak. 2) the main jet is clogged (it could also be the main jet is too small but sounds like it was previously fine, so that’s unlikely) you’ll need to take the carb apart and give it a good cleaning.

How much does a Mercedes SL600 convertible cost?

However, that low price doesn’t come without any issues for sure. And that’s the case here in the $5,000 Mercedes SL600 bought by Hoovies Garage. In the video above, you could see Hoover whip out a long list of issues he could find in the five-grand-worth Mercedes convertible.

What’s the difference between a Zonda and a SL600?

There were also oil leaks, as Hoover pointed out, as well as a problem with the car’s famed hydraulic suspensions. Hoover also noticed how quiet his new old SL600 is, unlike the Zonda it shared the engine with, so he’s up for tweaking the exhaust as well.

Why does my Toyota Tacoma hesitate to accelerate?

If this mixture is thrown off in any way, it may result in an engine running too lean (not enough air), or too rich (not enough fuel). An engine that is hesitating to accelerate is most likely dealing with a fuel/air mixture that is too lean.

Why does my car hesitate when pulling away from a stop?

Delay in acceleration happens when the engine does not get enough power. It needs more power than driving at a constant speed when pulling away from a stop. That power comes from the systems that control the fuel and airflow supply.

When do you Know Your Car is not accelerating?

The symptoms that your car is not accelerating the way it used to may occur to any vehicle. You may not notice the problem on regular days along the usual routes but they become clear when you decide to drive up a steep hill or accelerate to move into the fast lane.

What does it mean when your car hesitates when accelerating?

Instead of going faster by stepping on the accelerator pedal, the speed will be reduced. The vehicle may even stumble entirely during these seconds. This is what it means when the car engine hesitates.

When does power come back on during acceleration?

The power comes back and then off again cycling every second or so during low rpm. Only happens during acceleration. When I open up the throttle it hesitates then all of the sudden the engine responds. It seems to be worse in the lower gears (1 & 2) and lessens in the higher gears.

What does it mean when your engine hesitates under load?

An engine that hesitates, stumbles or misfires when accelerating or when it is under load, is an engine that is either sucking too much air, not getting enough fuel, or misfiring. If the Check Engine Light comes on, you may find any of the following codes: P0171, P0174 Lean fuel condition codes P0120 to P0124 Throttle position sensor codes

If this mixture is thrown off in any way, it may result in an engine running too lean (not enough air), or too rich (not enough fuel). An engine that is hesitating to accelerate is most likely dealing with a fuel/air mixture that is too lean.

An engine that is hesitating to accelerate is most likely dealing with a fuel/air mixture that is too lean. Engine’s that are running inefficiently will begin to show signs like hesitation which will only become worse over time. If you notice some symptoms like hesitation, you should have your vehicle inspected immediately.

What happens when your engine hesitates before accelerating?

Consequently, After the engine hesitation it goes back to normal; but it may take a second or two to respond. Everyone wants their vehicle to accelerate smoothly; so it can be frustrating when that does not happen.

If the TPS malfunctions, the engine speed cannot be controlled by the accelerator pedal and engine speed will increase or decrease without any press or depress the pedal. Report this ad #4 – Dirty or Clogged Fuel Filters A dirty or clogged fuel filteris another reason for a car not accelerating like it’s supposed to when required to do so.

A bad TPS can easily cause jerking hesitation, since the computer thinks you’re rapidly opening and closing the throttle. If everything in the world seems to be going wrong at once, check your engine and frame’s ground straps and the battery connection. A bad ground will cause everything to act up, including the computer.

What causes a car to have no power when accelerating?

3. Defective Fuel Pump. If the car has no power when accelerating, it means there is some defect in the fuel pump. A fuel pump supplies fuel in the gas tank for the engine for combustion. Further, it also accommodates the engine’s need by regulating the pressure for the fuel.

What causes the engine speed to increase when you press the gas?

A slipping clutch causes the engine speed to increase while the ground speed remains constant. The mass airflow sensor/meter is attached to the inlet air cleaner. Its function is to measure the mass of air flowing into the intake.

When does a car lose power while driving?

Here’s one of the most expression you often encountered in car loses power while driving situation. You often encounter this situation when suddenly running at an unusually high speed. The soot in the combustion chamber fell into the mouth of the valve so it could not be closed, the machine died suddenly.

Why is my car losing power at low speeds?

If the pressure is low the fuel injectors will not be able to spray the correct amount of fuel into the combustion chamber and that will result in a loss of power. A faulty fuel pump will not pose problems at low speeds but when you are looking for quick acceleration you might be left wanting.

Why does my car not accelerate past 40 mph?

If your accelerating won’t go past 40 mph, then there might be a problem with your exhaust pipe. It might be blocked; you will need to take it to the mechanic.

What causes car RPMs to go up but not down?

There might be a leaking vacuum hose in the car, hoses deliver air and fuel to the combustion chamber. If it is leaking, the air will mix with the gas causing the RPMs to go higher than it should be. Another thing to look out for is a clogged air filter if the air is having difficulties entering the combustion chamber.

Why does my car not accelerate when I step on the gas?

It can be very annoying when you step on your gas pedal but the car is not accelerating. It might be that the car isn’t accelerating at all or it isn’t as fast as it should be. There are so many reasons why your car is not accelerating; it varies from simple to very complex problems.

Why does my car lag when I accelerate?

If any of the components in your fuel system stop working correctly, like your fuel injectors, fuel pump, or fuel pressure regulator, then your engine won’t get the proper amount of fuel it needs for combustion. This will cause your engine to lag, stumble, or hesitate.

A vehicle with a combustion (gas or diesel) engine requires an exact mixture of fuel and air to run efficiently. If this mixture is thrown off in any way, it may result in an engine running too lean (not enough air), or too rich (not enough fuel).

Why does my car hesitate when I Turn on the gas?

There are a handful of other issues that can cause your engine to hesitate as well. Bad Fuel Pump: Your fuel pump is what moves the fuel from your gas tank to your engine so that you can actually have the combustion reaction to get going in the first place.

If any of the components in your fuel system stop working correctly, like your fuel injectors, fuel pump, or fuel pressure regulator, then your engine won’t get the proper amount of fuel it needs for combustion. This will cause your engine to lag, stumble, or hesitate.

If you notice some symptoms like hesitation, you should have your vehicle inspected immediately. Mass Airflow Sensor: The mass airflow sensor measures how much air is entering the engine and relays this information to the vehicle’s computer so that the right amount of fuel can be delivered from the fuel injectors.

What causes your engine to hesitate during acceleration?

Top 10 Reasons Your Car Hesitates When Accelerating or Driving Bad Throttle Position Sensor. The throttle position sensor monitors the throttle valve’s position and then relays this information to the engine control unit. Vacuum Leak. If any of the vacuum hoses around your engine become damaged or worn out, you could experience air leakage from them. Faulty Fuel System. Faulty Ignition System. Dirty Fuel Injectors.

Why does my engine hesitate during acceleration?

In essence, delay or hesitation of the engine during acceleration happens when the engine does not get enough power , and it needs more power to accelerate from a dead stop than when maintaining the speed of a moving vehicle. The engine generates power by creating combustions in its chamber.

What causes hesitation during acceleration?

One of the most common causes of stumbling or hesitation during acceleration is a fouled spark plug (or plugs). This is a simple diagnosis and a simple fix. Remove the plugs and check the electrodes for wear and/or oil fouling them.

Why would my car hesitate on acceleration?

A failing or stuck sensor relays the wrong information, so the engine does not get the correct amount of fuel it needs, resulting in suboptimal energy generation and thus will cause the car to hesitate during acceleration from a stop or while driving uphill.

Why does my maxima not accelerate when the RPMs go up?

If your Maxima won’t accelerate, but the RPM’s go up it’s usually not going to be an engine related issue. Somehow, the power that your engine is creating is not making it to the rear wheels. This is typically a transmission related issue. Here are the most common cause of acceleration with the RPM’s going up:

Why does my Nissan Maxima not start up?

The timing chain (or belt) is responsible for keeping the upper valve train synced with the crankshaft. This is vital for spark timing. If the timing is off a little and the engine still runs, the timing belt may have skipped. If it has jumped too much the Maxima may not even fire.

Why does my car sputter when I drive?

Driving should be smooth. But, if you are driving and your car’s engine starts sputtering the first cause of concern would be low fuel. However, if your fuel gauge is full it could be a symptom of further engine problems. A blocked fuel injector can prevent fuel from reaching the combustion chambers.

What can I do to stop my engine from sputtering?

You can use a reliable scanner that is able to read and troubleshoot the codes. You can remove the fuel filter and physically test the flow of liquid by blowing through it. A good filter should be able to have a smooth flow when air pressure passes through it. Poor fuel pressure will force the engine to run on lean fuel causing the sputter.

Why does my car sputter when I Turn on the engine?

The fuel filter ‘s job is to filter the fuel going to the fuel injectors and then enter the engine. A clogged fuel filter can cause the engine to get too low fuel pressure or cause a clogged fuel injector. Low fuel pressure will cause the engine to run very leanly, and therefore it may cause the engine to sputter.

What causes a car to have slow acceleration?

This is then mixed with air and ignited by the spark plugs. When the fuel filter is dirty, then you have less fuel going to the combustion chambers. This will cause your car to experience slow acceleration. You can clean your fuel injectors and the problem may be solved. 3. Vacuum leak

What causes car engine to hesitate when accelerating?

The exhaust gas recirculation valve, or EGR valve, may be damaged and causing a leak. This is known to cause engine hesitation problems, so it should be addressed. If you are using bad fuel which is has been sitting in your tank for too long or is too low of an octane for your engine, it can cause many different problems.

What does it mean when your car engine is spluttering?

A spluttering engine is a cause of concern for many motorists. It could mean that your fuel injectors are clogged and are no longer supplying the right amount of fuel. If the catalytic converter is faulty, harmful gases can find their way to the atmosphere. Some of these gases, like sulfur, are identified by their strong egg smell.

Why does my car hesitate when I pass someone?

Or, worse yet, you try to pass someone on a two-lane road, punch the gas pedal, and there’s a brief hiccup before you start around them. That’s usually termed as “stumble and hesitation,” and it can be maddeningly difficult to pin down.

Why does my car stall at high speed?

The engine can stall at high speed, at low speed, or even at idle. A faulty throttle position sensor will not let your car accelerate normally. Though this doesn’t happen all the time. You may experience slow acceleration, acceleration surge at both high and low speeds, hesitation or delay in acceleration, and other related symptoms.

What happens when you hesitate at the throttle?

5) While driving at normal road speeds (after the hesitation) or accelerating and the throttle is not fully closed, there is no miss whatsoever, and the engine performs very smoothly. While ever the throttle is partially or full open, the engine performs very smoothly and with normal power, apart from the initial hesitation.

What does hesitation mean on a Ford truck?

Hesitation and power loss are signs that something is wrong, and if left unfixed, can get worse. Usually, regular maintenance will prevent any problems, but like anything else sometimes things slip by or just fail prematurely.

What should I do if my engine hesitates at idle?

A quick way to check the intake manifold and throttle body gaskets: Spray some carburetor cleaner around the gasket while the engine is at idle. If there’s a leak, you’ll notice a difference in engine idle.

Are there any problems with the 1993-2000 850?

Fortunately, the shift interlock micro-switch is fairly easy to replace. Many 1993-2000 850, S70, C70 and V70 models can have issues with the ABS control module that can cause the ABS warning lamp to illuminate.

Can a bad throttle position sensor cause idle surging?

Idle surging can be caused due to other issues in the car, but if it happens in conjunction with other throttle position sensor symptoms, the culprit is often the TPS. At idle, the ECM will not get the correct information and the throttle will variate randomly causing idle surges. 3) Check Engine Light