95 Caprice Fuel Related problem

Ok i have done my research on this site and other sites...but long story short the problem i having is....


Riding on the interstate car just stalls out...i was told it was the fuel pump...so i drop the tank and do what i do...the old feul pump look burned to shit and the wires where destroyed a lil as well....so i change the wires and the fuel pump...car still does nothing...i change some fuses that where also blown, now after all that it starts up and shuts right back down, so what could the problem be now...i feel like im one step away from getting it right but what needs to be done now...i also changed the fuel filter and strainer...

somebody help...:banghead:

ok, i poured a lil bit of gas into the tb to see if would start then and that it did...but of course it cut off because it didnt have enough gas...so i can find out why the gas isnt going through the system or whatever...do i need to go back in the tank and check the pump again...i changed the fuel filter

Test fuel pressure at the test port near the regulator. It's a lot easier than removing the tank. If the pump is not producing 37 PSIG ±3 PSIG, make sure the pump has power. The fuel pump relay is in the underhood electrical center.

ok, i poured a lil bit of gas into the tb to see if would start then and that it did...but of course it cut off because it didnt have enough gas...so i can find out why the gas isnt going through the system or whatever...do i need to go back in the tank and check the pump again...i changed the fuel filter


replace the fuel regulator it is located on the rear of the intake manifold. inside is a screen. this screen is most likely loaded with crap. i would just get new regulator...............hopefully if it is dirty your injectors did not get plugged with crap......

replace the fuel regulator it is located on the rear of the intake manifold. inside is a screen. this screen is most likely loaded with crap. i would just get new regulator...............hopefully if it is dirty your injectors did not get plugged with crap......


I have been around these cars awhile, active on several LT1 specific forums and this is the first I have ever heard this suggested.


I am with Blue Bowtie on this one, check pressure, if no pressure as I think you will find then start electrical diagnosis.

If a screen at the regulator plugged it would present as trouble under load LONG LONG before it would restrict so badly it would not start and idle.

Ok i have done my research on this site and other sites...but long story short the problem i having is....


now after all that it starts up and shuts right back down, so what could the problem be now...i feel like im one step away from getting it right but what needs to be done now...i also changed the fuel filter and strainer...

somebody help...:banghead:


because of this statment i believe that the flow is restricted as the engine starts but dies immediately. the regulator plugged will do this and in the oem service manual it actually lists this as a check with this issue.

I own helms manuals but with 8 years and over 185K miles of LT1/L99 ownership the manual is the last place I look. Enusiasts have a MUCH better feel for what actually goes wrong over time than the guy who wrote the manual when the car was showroom new.

The wiring from the connector under the trunk all the way to the pump and the ground connection in the trunk are actual common sources of trouble. So much so that most of us who modify our cars run relay harnesses of larger gauge wire to the rear of the car to up volate and reduce resistance and therefore heat. You already found electrical issues, now you just have to find the rest of the damage they caused.

I own helms manuals but with 8 years and over 185K miles of LT1/L99 ownership the manual is the last place I look. Enusiasts have a MUCH better feel for what actually goes wrong over time than the guy who wrote the manual when the car was showroom new.

The wiring from the connector under the trunk all the way to the pump and the ground connection in the trunk are actual common sources of trouble. So much so that most of us who modify our cars run relay harnesses of larger gauge wire to the rear of the car to up volate and reduce resistance and therefore heat. You already found electrical issues, now you just have to find the rest of the damage they caused.

I agree that you will not find what the problem is buy looking at a manual or plugging in your scanner ! you gotta get dirty and search for defects........

well i broke this lil hose think the other day ...this was after i had already changed the fuel pump...but it was old hard and brittle which is why im assumin it broke so easily..
this lil hose like thing in the middle between the two larger hoses..
http://i54.photobucket.com/albums/g85/cwoodley3/mychevy015-1.jpg
this is the other end of it ...it goes somewhere near the schrader valve...you see the that one lil hose thats next to a hole which seems to be where another hose would go...thats where it broke off at..

http://i54.photobucket.com/albums/g85/cwoodley3/mychevy017-1.jpg
...i still need to fix this...even though the car still wasnt not startin before this..

That's the vacuum line coming off EGR Solenoid to EGR vacuum source port

That's the vacuum line coming off EGR Solenoid to EGR vacuum source port

this is the source vacuum for the egr control valve. repair this line as you now have a large vacuum leak which can cause starting problems if you notice next to the egr is your fuel regulator.....also check the PCV valve hose for cracks in the 90deg rubber hose that it connects to...in this immediate area 3/8dia hose.....

this is the source vacuum for the egr control valve. repair this line as you now have a large vacuum leak which can cause starting problems if you notice next to the egr is your fuel regulator.....also check the PCV valve hose for cracks in the 90deg rubber hose that it connects to...in this immediate area 3/8dia hose.....

where is the pcv valve located..

where is the pcv valve located..

that 90deg hose that is sticking out of the intake manifold in your picture that needs repair well its about 2inches toward the front of the vehicle from that hose ..this larger 3/8inch hose goes to the PVC valve. the pcv valve should be replaced every 25,000mi so if this has never been done do it as well....the pvc valve sets into the intake manifold in a rubber grommet it just slides out....but the hose going to it is at this age suspect for leaking....

ok so today im told that its more then likely my theft system, because the pass key fault light had been on for so long its possibly a broken/damaged wire from the ignition lock cylinder which in return cuts fuel off...question 1 is where is the ignition lock cylinder and the wires

ok so today im told that its more then likely my theft system, because the pass key fault light had been on for so long its possibly a broken/damaged wire from the ignition lock cylinder which in return cuts fuel off...question 1 is where is the ignition lock cylinder and the wires

in your vehicle when built it has a anti theft ignition key.. the key has a resistor when you put key in ignition it measures the resistance and if its proper like my key is 1700ohms then the pcm will allow engine to start..... now there is a way to bypass this I never did but it can be bypassed and i believe like in my case i would find the appropraite terminals and put in a 1700ohm resistor now with any key i would be able to start engine ..of course it would have to be properly cut to fit ignition switch..but the other reason owners do this is because this key of the proper resistance costs 20-30.00 at dealer..........you get so many attempts with wrong resistance then you will have to wait some period of time before it will allow restart even if you find a good key.............

ok back to work on the car today...Ok so nothing has worked, I dropped the tank again and i check out the fuel pump and walllaaa one of the wires was off, so i pop it back in its place but before putting everythin back to together i wanted to make sure it would work...SO i turn the car on and it starts but then shuts back off again(i think the only reason it started was because of the lil bit of gas in the TB...Do i need to put the tank back on to make sure that its actually working because in the lil plastic part that goes from the fuel pump to the lines there is gas in it and when i started the car it bubbled up like it was flowing up through the lines ...or will i not be sure unless i put the tank back on and put some gas in it.

make sure all those wires are securely fastened in the fuel tank... put 3 gallons of gas or more in tank.... then turn key ignition on wait 2 seconds and repeat 3x then go for start.... make sure battery is charged... did you fix those vacuum leaks ..... check for other hoses broken etc.......??????? how was your key was the resistor ok?????

Does the resistor in the key just cut the fuel source off or the ignition and fuel? I don't know for sure but I always thought it interrupted the ignition source too. If what I stated is true, then it wouldn't be the problem since its got spark. Just a thought. I'm thinking its a bad ground or wire in the harness for the fuel pump by the tank. Figure its exposed to the elements so corrosion is possible. Easy to check. I always start with the simplest first. Change the relay for the fuel pump and check for pressure. If you have good pressure your injectors may not be firing. I know there is a way to safely check the injectors with out burning them out. If you dont have noid lights you can use a volt meter but not at 12 volts! The injectors have about 4 or 6 volts going to them. Maybe someone can help explain this better.

Does the resistor in the key just cut the fuel source off or the ignition and fuel? I don't know for sure but I always thought it interrupted the ignition source too. If what I stated is true, then it wouldn't be the problem since its got spark. Just a thought. I'm thinking its a bad ground or wire in the harness for the fuel pump by the tank. Figure its exposed to the elements so corrosion is possible. Easy to check. I always start with the simplest first. Change the relay for the fuel pump and check for pressure. If you have good pressure your injectors may not be firing. I know there is a way to safely check the injectors with out burning them out. If you dont have noid lights you can use a volt meter but not at 12 volts! The injectors have about 4 or 6 volts going to them. Maybe someone can help explain this better.

if the key is incorrect it will not crank no fuel pump and because its not cranking there wil be no spark.... as rotation is required for this to happen.....then after so many tries I forget how many then you will have to wait for some period of time before it will start when correct key is used... so even if you have correct key it will not start if you have exceeded the number of tries with bad key... these resistors in key fall out ,,,,most owners are unaware that it's a resistor ,,,think its a key ornament.........

I have someone coming tomorrow to do a bypass for the pass key and he will be checking for broken wires also and hopefully this is the problem

What does the fuel pump have to do with the motor cranking by the means of the starter? He said when he introduced gas to the TB it fired up until that fuel was burned off. That means there is spark.

What does the fuel pump have to do with the motor cranking by the means of the starter? He said when he introduced gas to the TB it fired up until that fuel was burned off. That means there is spark.

this i believe is a female type .... and it was stated that she was told she had a key issue as well as this fuel pump /wiring mess then vacuum lines broken so this is where it's at now..........found wire off of the fuel pump in tank......

got it looked at and checked..the ignition was a problem..and some broken wires...the pcm was not getting the signal from the by-pass...but the tank was not on the car so we are going to put the tank back on and by-pass it again because the sending unit is grounded through the tank(from what he said) so when we put the tank back on and put the bypass on and see if that works...please cross your fingers for me on this one...im almost done...
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Ok so this is where im at...
CHANGED FUEL PUMP
FUEL FILTER
FUEL PUMP RELAY...
Got it checked and was told something about some broken wires dealing with the ignition...Also when the pass key bypass thing was put in the pcm was not reading the signal from the by-pass(or something like that)...Guy was suppose to come back and check it out for me but he never called...He said in reality the car shouldnt even be starting because he was getting nothing from the ignition when he tested it, there are some broken wires he said...Ok so where does this leave me...I have some broken wires dealing with the ignition(how do i repair them), where do i get this by-pass thing that he had and how do i install it...and also he said that the pcm was not picking up the signal from the by-pass so it was not turning on the fuel pump(how can i fix that problem)...called dealership they told me to bring it over there and they going to charge me one hundred and something to put it on the machine and whatever is wrong they can fix it for a arm and a leg...

Ok so this is where im at...
CHANGED FUEL PUMP
FUEL FILTER
FUEL PUMP RELAY...
Got it checked and was told something about some broken wires dealing with the ignition...Also when the pass key bypass thing was put in the pcm was not reading the signal from the by-pass(or something like that)...Guy was suppose to come back and check it out for me but he never called...He said in reality the car shouldnt even be starting because he was getting nothing from the ignition when he tested it, there are some broken wires he said...Ok so where does this leave me...I have some broken wires dealing with the ignition(how do i repair them), where do i get this by-pass thing that he had and how do i install it...and also he said that the pcm was not picking up the signal from the by-pass so it was not turning on the fuel pump(how can i fix that problem)...called dealership they told me to bring it over there and they going to charge me one hundred and something to put it on the machine and whatever is wrong they can fix it for a arm and a leg...

this sounds like someone reconfigured this starting system...wires don't just break.....I will have to think about this....dealer is out of the equation as the will charge for diagnosis and accomplish nothing... purhaps looking in phone book for a repair shop with good electrical skills in automove area call and explain....

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