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Help! fuel

jjohnny

New member
Joined
May 12, 2008
Messages
4
Location
south carolina
Corvette
1991 Black Convertible (Vetsy)
hi im new here and learning alot :upthumbs. but im kinda confussed. ok so my dad gave me a 1991 chevy corvette c4. she was sitting in the garage for year 1/2 or two years without being crunk up. picked her up 3 weeks ago on saturday. got her home and replaced battery, plugs, fuel filter, rotor & distributor. drove her to work last monday and she was running really rough, loss of power, smoking. she shut off and would not crank until after she was sitting up for awhile. did a little research and replace the oxygen sensor which was really really dirty and went ahead and changed the pugs again but when i took the out there was gas coming off them. still would not start with new plugs! all it would do is turn over and not start. i got the owners manual to look at the fuse box. i took out the 20 amp fuel injector 1 fuse and then the 10 amp fuel injector 2 fuse. SHE STARTED for 3-5 secs. then shut off. put the fuses in and repeted the process. same thing. im lost! :confused fuel injector/s, fuel pressure regulator, etc bad? please help ;help
 
jjohnny, Welcome to CAC and vette ownership. Would recommend you purchase the GM service manual(s) for your 1991. I found mine on e-bay. FSM will really help you pinpoint the cause and minimize replacing good parts. Is the engine service light coming on? It appears that you are getting fuel, and a dirty O2 sensor maybe a hint of a "rich" condition. Have you checked for spark at each plug? I would check the fuel pressure and run a leak down test to make sure the injectors are not leaking. You can disconnect each injector and measure the resistance. Post the readings. They should all show similar readings.
 
Welcome

Wow what a nice car to get as a gift congratulations.

It appears you are trying to understand how the Corvette engine runs and what the different pieces do. Here is a thought I have on your problem.

Throttle Position Sensor (TPS)
Copied from 1993 Service Manual
The Throttle Position sensor (TPS) is a potentiometer connected to the throttle shaft on the throttle body. It is a potentiometer with one end connected to 5 volts from the ECM and the other to ECM ground. A third wire is connected to the ECM to measure the voltage from the TP sensor. As the throttle valve angle is changed (accelerator pedal moved), the voltage output of the TP sensor also changes. At a closed throttle position, the voltage output of the TP sensor is low (approximately .5 volt). As the throttle valve opens, the output voltage should be approximately 5 volts.

By monitoring the output voltage from the TP sensor, the ECM can determine fuel delivery based on throttle valve angle (driver demand). A broken or loose TP sensor can cause intermittent burst of fuel from the injectors and cause an unstable idle, because the ECM detects the throttle is moving.

If the TP sensor circuit is open, the ECM will set a DTC 22. If the TP sensor circuit is shorted a DTC 21 will be set. A problem in any of the TP sensor circuits will set either a DTC 21 or 22. Once a DTC is set, the ECM will use a default value for TP sensor, and some vehicle performance will return.

A personal note, when my TPS failed it DID NOT set a code other than to tell me the ECM was bad.


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:welcome

As John said....wow what a gift!!!

When it was running and smoking...what color was the smoke? Black would indicate a rich condition, blue would indicate burning oil, white (almost steam-like) would indicate coolant (antifreeze).

Sounds like maybe you're just getting entirely too much fuel to the cylinders...faulty fuel pressure regulator, Coolant Temp Sensor, TPS...any number of things. Make sure to check for stored trouble codes!

Bill
 
yes it was putting out black smoke. i bought a code reader from local auto store and the only code was 12. i wonder if the inj fuse 1 or inj fuse 2 has anything to do with faulty fuel pressure regulator, Coolant Temp Sensor, TPS etc etc.. i know for a fact that when i turn the key to crank it all you smell is fuel. this tells me shes getting way to much gas when the car is turning over? got home last night and tried to crank her and i think something is draining the battery now. lol just bought a new interstate mtp-75 last monday. not that im trying to get into another problem solving issue lol. (scratches his head) i may get a side mount battery disconnect switch to put on it till i figure out the gas issue
 
p.s. thank you all for the nice welcome. 1 small question. how do i get my car picture under my name like John Robinson & TedC :)
 
hi im new here and learning alot :upthumbs. but im kinda confussed. ok so my dad gave me a 1991 chevy corvette c4. she was sitting in the garage for year 1/2 or two years without being crunk up. picked her up 3 weeks ago on saturday. got her home and replaced battery, plugs, fuel filter, rotor & distributor. drove her to work last monday and she was running really rough, loss of power, smoking. she shut off and would not crank until after she was sitting up for awhile. did a little research and replace the oxygen sensor which was really really dirty and went ahead and changed the pugs again but when i took the out there was gas coming off them. still would not start with new plugs! all it would do is turn over and not start. i got the owners manual to look at the fuse box. i took out the 20 amp fuel injector 1 fuse and then the 10 amp fuel injector 2 fuse. SHE STARTED for 3-5 secs. then shut off. put the fuses in and repeted the process. same thing. im lost! :confused fuel injector/s, fuel pressure regulator, etc bad? please help ;help

well like everyone said...welcome to the CAC if you have a question dont hesitate to ask in the forum...someone out there knows all the answers im sure.......also i have to agree...nice gift!! as far as adding pics go to user cp..then on the left are a group of options..you will have a choice to edit your avatar etc....

have fun... and post some pics:beer
 
well like everyone said...welcome to the CAC if you have a question dont hesitate to ask in the forum...someone out there knows all the answers im sure.......also i have to agree...nice gift!! as far as adding pics go to user cp..then on the left are a group of options..you will have a choice to edit your avatar etc....

have fun... and post some pics:beer


just added you on myspace :cool
 

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