20 Most Recent 1994 GMC Jimmy - Page 3 Questions & Answers

Hi Nancy, this code says you have a MAP sensor fault.

Glow plugs would be an obvious starting point. If you have a multi meter you can check at the rail to make sure the relay is kicking in when you put the ignition on and you are getting voltage down there. Next test would be to test the glow plugs current draw but you would need a good ammeter to do that. A good glow plug should draw at least 16 amps and 20amps on a good day. Jon

By "sticking" I am assuming that you mean that the brakes are staying applied (calipers are not releasing)and burning the brake pads and rotors up.

The most common cause of this is brake hoses.

The hoses that connect your calipers to the steel brake lines have an inner lining and a reinforced outer "shell". sometimes the inner lining tears loose from the outer shell inside the hose. (It cannot be seen by "looking" at the hose.) The inner lining then starts to act similar to a "heart valve" where it allows fluid to be pushed down into the caliper, then collapses inside the hose, blocking the fluid from returning to the master cylinder when the pedal is released. This can happen just because of the age of the hose, but is more commonly caused by someone allowing the caliper to hang by the hose while replacing the brake pads without using anything to support the weight of the caliper.

To diagnose this condition, raise and support the vehicle and remove the wheels. Make sure that the transmission is in "Park" (Automatic Transmission) or "Neutral" (Manual Transmission) and apply the parking brake. Then start the engine and apply the service brake. (Press HARD on the pedal) Shut the engine off, release the service brake and open the bleeder screws on the calipers. If brake fluid squirts out of the bleeder screw under pressure, then the hoses are the cause of the calipers not releasing.

There is usually a vacuum hose diagram decal under the hood.

it sounds like a classic fuel injection relay to me. switch the relay with a known good relay that is in another spot...headlight, a/c, etc. if a known good relay isnt the problem, look into bad wiring, possible injector, or PCM.

check the fuse block for a blown fuse, the one that controls dash gauges should be identified in the owner's manual.

passenger glove box, two fuel relays are located. If you can pull them out and shake them, and they have rattle sound, odds are they are bad. Also on some models i believe they can be located passenger side firewall under hood

you can have worn injectors over time the knozzle gets worn and it affects the spray pattern and along with that it affects the atomization of the fuel...but you can also have your injectors professionally cleaned with a pressurized treatment , most well equipped dealers and some independent shops will be able to do that service.. at the same time have them clean the throttle body and plenum of any residue build up... please rate my help, thanks...

If egr valve is stuck open can cause raunchy smell from exhaust, hense high readings. usually this causes rough idle though.

check your fuses and the moter could be forzed up and need to be un stick..are my need to put new one in...you also have a lock on some of these models..

may be bad starter

I just had the same problem, when you change the distributor did you make sure the number one cylinder is up and Te rotor button is on the number one

under the front carrier very bottom of the front end sticks out a bit parallel to axel

check the temperature sensor for the computer. it may be telling the computer that the engine is still cold and causing the engine to run too rich at warmer temps

Concentrate on the starting circuit: from the ignition switch to the neutral safety switch to the starter relay to the starter solenoid on the starter. If it won't crank, one of these parts or the wiring associated is not working right. Quite often the electrical contacts in the starter solenoid become pitted, slightly burned maybe, and lose contact. If you have power on the solenoid wire when key is held in crank and starter won't operate, the solenoid is the problem.