20 Most Recent 1991 Chevrolet C1500 - Page 8 Questions & Answers

Chic Mechanic, I like that. Take and smear the grease from your fingers on your face like war paint and let out a Zenna yell.

The IAC could have some carbon build up on it, or not working properly. Unplug it and see if the motor just dies. You can also remove it and clean any carbon off. Also carbon can build up on the EGR and keep it open a little bit. And check your ignition timing. If you have an under hood label it should give instuctions and specs. It should tell you there is a tan (or tan with black stripe) single wire that needs to be unplugged. I don't recall the exact location but it will be in the large computer harness (usually sticking out of the loom) under the hood where it goes into the truck or under the dash near the ECM.

air blows out only defrost possible cause could be faulty ac and heater mode switch or broken vacuum line to ac and heater vacuum actuator.you have to remove ac and heater control switch to check it out.

THE WIRE YOUR LOOKING FOR IS PURPLE

The firewall is that whole area that is under the hood bellow the winshield and between the fenders. Its right behind the motor, you can't miss it. It seperates the engine compartment from the inside of the cab.

Hello, Your Code 32 means that an O2 circuit is reading high. Its position is Bank1 spot1. The Code 33 would go to a vehicle with a turbo or supercharger. Code 33 concerns the Turbo bypass circuit, if so equipped.

You can continue to get free scans at Autozone, Advance or Oreilys. The O2 sensor should be replaced or check the wiring for a grounded wire to the O2 sensor.

If it is located on the transmission it should just unscrew. Be prepared if fuild leaks out when removed.

Hello: Remove the distributor cap. Check the rotor, see if there is a black spot where the metal piece makes contact with the carbon stick out tha makes contact with the coil. Did you replace that piece when you replaced the coil, it should have come with the new coil? Also did you reinstall the ground strap that was under the coil and went to the stick-out that the black connector plugs into the cap?

Is it TRYING to go up but can't? You could have high resistance in the ground circuit to the passenger switch. It takes a LOT less power to move the window down than it does to make it go up. There mak be good enough ground to the switch to make it go down, bt not up.

Since it works from the driver's door, this pretty much eliminates the B+ circits and the grounds for the driver's switch. Since the passenger switch itself has been replaced twice, I would think that eliminates the switch itself as the cause. The ground circuit to the passenger switch is the only thing left.

This theory can be easilly verified by running a jumper from Pin "J" BLACK wire at the passenger switch t the battery negative post. If the window now goes up and down from the passenger switch, the ground circuit needs to be repaired.

if the light is ok, then there might be a fuse in the fuse box. I have a malibu and there is a fuse for each headlight. there could be on yours also!

If you are sure that your freon is not low..then stick with the low pressure switch circuit.
Check the wiring on your plug very thoroughly.. These have a problem on many vehicles..
Look at the prongs on the inside of your switch to make sure that neither pin has been bent or damaged. If all this checks out ok.. then plug it all in and shake or wiggle wiring to see if anything makes the system come on..

If all this fails to help you.. then I would unscrew the pressure switch and make sure that you are depressing the schraeder valve..(the valve stem looking guy that is in your accumulator).. There could be a problem with getting actual pressure to make the switch.. Good Luck.. Let me know how you come out..

I have seen this problem, if you have no oil pressure the engine would be rattling, the oil pressure sending unit could be bad, you can buy a oil pressure gauge to test and make sure oil pressure is ok, the sending unit may fix your problem.

Ignition module on distributor?