Do you need to adjust the base idle on a GM TBI?
For whatever reason you have determined that you need to adjust your base idle on your GM TBI vehicle. In most cases this is only done if you have modified the internals of your engine or you have swapped a larger throttle body onto your vehicle.
Where is the ECM on a GM TBI?
Start by jumping the A&B pins on the ALDL (Assembly Line Data Link) connector under the dash. Pins A&B are on the upper-right-hand side. These are the same two pins you jump to read codes from the ECM. Now turn the key on (the Check Engine light should be lit) and leave the key on for at least 30 seconds.
When to spray fuel on a GM TBI?
On a side note the ECM will note spray fuel untill it sees ~400 rpm! 8 people found this helpful. You can scan codes and live sensor data from this truck and most other GM OBD1 vehicles with the right equipment.
What should the voltage be on a GM TBI?
Loosen the two torx screws holding the TPS in place, but don’t remove them. Rotate the TPS until the voltmeter reads between 0.45 and 0.55 volts, with 0.50 being ideal. Tighten the mounting screws (carefully, they thread into soft aluminum) and re-check the voltage to make sure it’s still within range.
What makes a 95 TBI Chevy run crappy?
2–EGR….did you use the VIN # and go to the dealer for the correct one? to test it ,disconnect the vacuum line and plug it and go for a ride. 3–When I removed the cat on mine ,the 02 sensor set the check engine light on and was going thru more gas but didn’t run crappy.
What is the TBI code on a 1990 Chevy truck?
Consult a service manual or see below for any check engine light code definitions. You can use a late 80’s or early 90’s GM TBI definition. If you have access to a scan tool use a hook up for a 1990 350 cu. in. 5.7L Chevrolet truck. For some scan tools enter VIN 10th“L” 3rd“C” 8th“K”.
What kind of scan tool do I need for GM TBI?
A scan tool can be used and set up for a GM TBI application to read the data, or to check for stored codes. Consult a service manual or see below for any check engine light code definitions. You can use a late 80’s or early 90’s GM TBI definition. If you have access to a scan tool use a hook up for a 1990 350 cu. in. 5.7L Chevrolet truck.
What’s the gas milage on a 95 TBI?
Finally, when it dieseled, it threw a CTS code stating that a temp of -40f was indicated (in Houston TX). Replaced the CTS, problem went away, and my gas milage went to 17 mpg (no joke) on a 5.7 TBI with 200k miles. Beat it to fit. Paint it to match.
How to adjust the idle of a 1991 Chevy?
Put the wheel chocks around the front wheels of the Chevrolet and set the parking brake. Pop the hood and take off the air cleaner on the engine by taking off the factory wingnut with your hands and setting the air cleaner away from the engine bay. Have your assistant start the engine.
Where is the idle speed setting on a Chevy?
Locate the vehicle specifications sticker, which is on the underside of the hood, and lists the factory idle speed setting. Tighten down the adjusting screw on the throttle cable linkage with the flathead screwdriver to raise the idle speed, and loosen the screw to lower the idle speed.
Why does my car run too low at idle?
Sometimes, the idle speed drops too low, and the engine could stall while you’re stopped. Other times, the idle speed could be too high, causing the engine to spend more gas than usual. You can adjust the idle speed to the factory specifications, or to your personal preference.
Put the wheel chocks around the front wheels of the Chevrolet and set the parking brake. Pop the hood and take off the air cleaner on the engine by taking off the factory wingnut with your hands and setting the air cleaner away from the engine bay. Have your assistant start the engine.
Where is the idle button on a GM TBI?
The “A” and “B” terminals are located on the top right of the connector. Unplug the IAC valve located on the passenger side, rear of the throttle body. Start the engine. Insert a T-30 size Torx driver into the Idle adjustment screw that is located behind the plug removed earlier.
Locate the vehicle specifications sticker, which is on the underside of the hood, and lists the factory idle speed setting. Tighten down the adjusting screw on the throttle cable linkage with the flathead screwdriver to raise the idle speed, and loosen the screw to lower the idle speed.
Sometimes, the idle speed drops too low, and the engine could stall while you’re stopped. Other times, the idle speed could be too high, causing the engine to spend more gas than usual. You can adjust the idle speed to the factory specifications, or to your personal preference.