helo my 92 vette after takeing out of storage for the winter was running like it had water in the gas added stuff to the fuel then tuned it up and still the same the last couple of weeks the idle has jumped to 1500 rpms my mech. says its the ecm when he read the syestem check the codes were all over the place could this be the problem or is there something else wrong
The scan tool displays throttle position in volts. The voltage should display between .23 - .59, with throttle closed and ignition “ON,” or at idle. Voltage should increase at a steady rate as throttle is moved toward Wide Open Throttle (WOT) about 4.6 volts.
The ECM has the ability to Auto-Zero the TP sensor voltage if it is between .23 and .59 volt. This means that any closed throttle voltage between .23 and .59 volt will be determined by the ECM to be 0% throttle angle, and should display 0% when the throttle is closed. A failure in the TP sensor circuit should (MY OPINION MAY NOT )set a DTC 21 or 23.
Copied from the service manual for a 93 model
Try this with the car running disconnect the TPS wire. The idle should slow down. It won't go all the way back to a normal idle but it should drop. I just went through this with my car. Unfortunately I went the ECM route before finding the TPS was bad.
Your mechanic should be able to test the TPS. I hope this saves you the cost of an ECM. Please post the cure for your problem when you find it.
well i replaced every sensor that there was and the problem turned out to be the distributor it self i put in a msd cap and a new dist. i would highly recommend a msd cap it has the low sucksion that will keep the moisture out of the cap
92 vette is running weird
Linear Mode
