Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
Sounds like the fuel injectors are not getting any fuel to the engine. I assume you hear the fuel pump run since you said you have 42-44 psi of pressure. For the engine control wiring diagram, click here. Check the INJ Fuse 10A (hot in run or start). If ok, check for voltage to the injectors at the pink/black wires. Can you hear the injectors clicking when cranking the engine? If so and still no fuel you may have to clean the injectors. If no clicking and you do have voltage to them you will have to check the ground circuits to the ecm/pcm driver with a noid light.
1991 Chevrolet Lumina-Sedan/Coupe 3.1L vin T MFI OHV 6cyl.
For an explanation on how MFI works, click here.
OEM/6 pcs. noid light set
•For checking electrical impulses from the wiring harness to the fuel injectors•Includes GM TBI, GM SCPI, GM PFI, Ford TBI, GEO TBI, Bosch PFI•See through design to check electrical pulses
Actually after rereading that it appears that the ecm sends a signal to the injectors versus turning off and on the grounds, although the wiring diagram does no good it just shows all the injectors wired together. You would use the noid light on the positive wire leading to the injectors.
I have already do all but one of those checks, so I will check the injectors for the ohms. My father said that he had the same problem with his lumina van, he says its the "Torque Converter Clutch Solenoid" , I don't see how this would cause the problem but I figure I can ask maybe you have seen the same thing.
I know the tcc is hooked to the brake switch so when the brake is applied it disconnects the tcc. Plus the tcc disengages the egr when its applied, but I don't see any correlation between the tcc and fuel injectors.
What result did you get at this step 4? Yes or no? Circuit 639 is the pink/black wire coming from ign fuse to fuel injectors.
I did not do that step and I will not be able to do it until tomorrow or monday
I don't think a 12 volt test light is fast enough to check fuel injector pulses, that is why a noid light is used.
Just cause #1 and #6 fuel injectors have a pulse doesn't mean the injectors are not clogged.
Did you recently purchase any bad gas or is the gas real old like 1 year? Why not try some of that gas from your tank in your lawn mower or tractor or another vehicle and see how it runs. Maybe you just got some bad gas.
Well injectors 3 and 4 where not working.. I went to the junk yard and pulled a couple of injectors. It started right up, however I now have a vacum leak that I have to find tomorrow. I am very thankful for your help. I do have one more question for you if you know. My fuel gauge works but its a quarter of a tank off, is there a way to calibrate the gauge so that it reports the right amount of fuel in the tank.
Not that I know of, if the fuel gauge is off by 1/4 tank you may have a bent rod on the sender or possible a dent in the tank or some other problem with the sender. I am not aware of any adjustments or calibrations.
Another note while looking that up I did find a tsb on "do not clean multec fuel injectors", click here. Apparently the ball and seat design of the Multec injector eliminates the need of ever having to use an injector cleaner.