hey guys my names rob and im workin on an 87 iroc with a tpi 350. Alittle background cars bin sitting for a long time. Decided to get her running put in new starter and new fuel pump tank and pick up. Car ran great the first couple of days of light start up and idle last day start the car up let it idle for a minute or so brought the rpms up to about 2500 then back to idle then car stalls out. Now the car starts and will stay running if you play with the gas alil but if you step on it its instant die out. Hooked up a fuel pressure guage to the fuel rail to find no pressure at all. So i figuered my regulator was bad so i pulled the tpi plenuem off and took the regulator out. I have fuel to the rails and regulator opening. now im trying to find out if its the actualy regulator. I have heard that if you clamp the return line and you get pressure the regulators bad if you dont get pressure the check valve in the pumps bad is this true? Please guys i really need help with this car thanks so much for your replies in advanced! -Rob

 

u said its been sitting.. when u did the fuel pump and pick up did u change the filter? did u drain the bad gas out of the tank while u had it out and replace it with fresh gas? u could easliy have a clogged fuel filter or bad gas.. or both..

 

when i did the pump i changed the whole 9 yards the actual tank itself the pick up the pump and the fuel filter the tank and pick up came out of a running and driving car and the filter was new cause thats what i thought but i have fuel all the way into the space between the rails were the regulator should be but no pressure

 

i would take the fuel rail out and look at it ive seen them become clogged with white junk before.. could be ur problem.. or u could have clogged or bad injectors..

 

i agree with Kris
mine did the same thing
It ended up that i had old crap in my gas tank from sitting and my fuel rail was clogged
the little bag on the end of the sending unit was full of crap too,and my rubber hose connected to the fuel pump and sending unit had a hole in it.
I also sea foamed my car to make sure i got all that crap out

 

Just be careful, seafoam is a great product but if you have alot of gunk in your fuel system, as it flushes through it will ultimately wind up in your injectors.

www.southbayfuelinjectors
516-492-6504

 

Haha i agree,happened to my buddy that has,or HAD a 96 bonneville

 

thanks guys but heres the wierd part when i took the regulator out i have fuel where it goes in the rail so today i clamed the return line and wala i started getting pressure so i nagged my dad enough to take me to advanced auto parts and i got a new regulator so tomorrow im gonna put it in and ill see if it fixes my problems and hopefully it will ill report tomorrow on how it goes thanks guys!

 

ok so i put the regulator in and put the car back together and were back to square one it takes forever for fuel to get to the fuel rail and when it gets there its like alittle stream not even one pound on the fuel pressure guage i have no clue what else to try would it matter that the pumps out of a 91 rs tbi?

 

Not sure if the pumps in TBI cars are the same or not but.....you put a used fuel pump in it!?

Thats your problem.

 

he said he put a new pump in it.. take ur fuel rails off.. i bet u when u take them appart and look down the rail there will be junk inside.. while ur at it disconnect the fuel line fron the filter and blow out the rail from the motor back with an air line..

 

im thinkin its the pump because i dont have alotta pressure out of the line from the pump itself so im thinkin it was a defective pump to start with maybe ill do it all over again with another pump....here we go again

 

You put the wrong fuel pump in... The TBI pumps are different, as they run ~15psi instead 40+ psi for TPI...

 

Thats where I got that the pump was used.

 

opps sry i missed that one.. and yes the tpi motors need more pressure and shame on u for using a used pump!!! speicaly after all the work it takes to get to the damn thing in the first place.. inless u take the easy wayout and cut the back panel to get to it.. but i wouldnt recomend that..

 

ya i know it was a stupid move it was my dads way of "saving money to get the car running" i told him the pumps were different and we should put a new pump in after all this work but he just ignored me ... here we go again and no i refuse to cut my floor up i love the car to much lol

 

but wait even with a 15 psi throttle body pump why would it run good for 2 days? and i dont even have 15 psi anywhere on my fuel lines

 

If it is a tbi pump you need a tpi pump for sure tbi won't work,
what is the fuel pressure now?

 

the fuel pressure is 0 at the moment

 

I could be mistaken, but I believe a tbi pump will pump up to 40 or more psi but will burn itself out very quickly doing it, thats probably why it ran at first, also the tbi cars have a piece of low pressure fuel hose connecting the pump to the pick-up, that hose has most likely burst because it couldn't handle the pressure.
So now when the fuel pump runs (if at all) the fuel is coming out the break in the hose and not going up the fuel line.
When you are ready to replace the pump don't use rubber hose to couple it to the fuel line, buy a pulsator valve instead.

 

bingo john 89 formula got it that little line had blown a hole in the side and was leaking fuel stupid suttle differences!

 

Thanks for all your replies guys my cars running like a champ now boy it sounds good to finally hear here scream!

 

now i have another question car runs and revs nice sounds good 60 psi of oil pressure all the good stuff but the car wont idle at all what could that be just from sitting?

 

I hav a 89 camaro irocz and I replaced to the fuel pump fuel sending unit and the fuel filter all brand new and I dont hear the fuel pump cumin on wat could it be

 

The easiest thing to check would be the fuse by the battery, there is a red wire on the positive battery cable it has a 20 amp fuse on it, if that fuse is blown the fuel pump will not work, one sign that it is blown is the check engine light does not come on when you turn the key.

 

i would replace all the plugs wires and cap and rotor.. i can almost bet that will stop the rough idle.. start with the cheaper ones if ur low on $$ get some good plugs, then get a cap and rotor and if the idle is still crappy then u probably have a burnt or chewed wire some where so get those.. have fun and easyiest way to get the the plugs is from underneath.. well most of them

 

Yea my check engine light doesnt come on wen I turn tha key I tried lookin for that fuse but I dont see it on tha battery wire

 

It's a red wire or it may be orange, it comes off the positive battery cable, there is a fuseholder on it that may be screwed to the radiator support.

 

Ok then thanks for your help imma check that out wen I get home

 

That FP fuse may be on the pass side inner fender just back from the battery. 1bad87z, your problem doesn't sound like tune up to me. Not that a full tune isn't a good idea. I suggest you check your EGR valve as it may be stuck open. Also, clean your IAC passages and quick test the valve's operation. To quick test IAC, just uplug it. The engine should speed up to about 1,100 rpm. Be aware that this test is generally done at idle so it may not work on yours. Clean the thottle body. Use a wire bore brush, carb cleaner and a rag. Spray the throttle bores with carb cleaner just til they're wet, then scrub with the brush and wipe clean with the rag. Repeat until the bores wipe clean.

 

ok then imma try that cause I been lookin for that fuse and cant find it nowhere

 

Whoever had the car cut the fuse off the wire and just strait wired it

 

Ok so here is the thing I changed out the fuel pump fuel sending unit fuel filter and fuel pump relay and the fuel pump still wont come on I know people have told me there is a fuse on the positive battery cable that could be the problem but whoever had the car cut the fuse off and just strait wired it so wat can I do now I need help on this

 

You need a 12v test light to test for power to the fuel pump relay. The large orange wire should have 12v constant. If not trace it back to the battery. Your's may have a fuse link in the supply wiring. The fuse link may have broken. Use your test light to find the break in the power supply.

If the supply is good to the relay, and because the TBI pump worked fine to start with, Im going to have you check your work. Go back over the install and check all your connections. Connect12v to pin G of the ALDL. This will power the fuel pump circuit. Use the test light to look for power at the tan or gray wire at the four pin connector C313 just above the fuel tank.

 

Yea well the pump didnt work before I changed out every thing it was a gummed up with stuff inside the fuel tank it was lik tree sap inside the tank it had been sitting for a few years but I cleaned all that out and just replaced everything and wat u said do that still go for the tpi cause mines is not tbi

 

I know your's is TPI. the power test for fuel pump circuit is the same for either.

 

Ok then imma try that thanks for tha help

 

Just throwing this out there hoping it might helps someone some day.
Most folks just think of bad/old gas as losing potential energy. But theres much more sinister problems that can occur.

When fuel is left in the tank for such a long time, condensation forms on walls and inner ceiling of the tank. The condensation (H2O) then falls into the fuel and sinks to the bottom. Aside from the water (down where the fuel pump pickup is) being REALLY hard on injectors specifically (can ruin a new injector instantly), in this layer of water a colony of bacteria/mold/yeast type stuff grows.
When a vehicle subject to such fuel conditions is first used after an extended period of non use, that "algae" is then sucked into the fuel system.
This is why alot of times, people will say, 'I have drained the fuel several times, and added new fuel, doesnt seem to help.'
Well, they have probably affectively killed the 'algae'. But the dead biomass is still in the tank, lines, fuel rail and injectors... plugging or atleast restricting the fuel system.

Hope this helps someone.

 

In such conditions, if you cant remove and replace components. The absolute best product to use is Startron.
http://mystarbrite.com/startron/

You can find it in the boating section at ChinaMart (Walmart).

Its never failed to bring dead gas back to life, and increase mpg and performance in every vehicle ive tried it in.

Im not affiliated with them. Just passin it along.

 

Ok I tested my fuel pump relay and fuel pump wires and im not gettin no power with the 12 volt meter and I tested it with the ohms meter and I am gettin conuity so wat could it be wring I need help with this somebody

 

Well, if your not getting 12v then thats a/the problem. ?

I have had a problem with the terminal that is actually in the fuel tank that the fuel pump plugs into. It had a slightly loose connection, and eventually would build up heat and fail. Once cooled off, it would flow current again.

 

Yea just mines has never worked since I got the car so its not goin off and coming back on

 

did you check power where the sending unit plugs into the car? its the 2 outside wires thats the best place to see if you have power my dad hooked 2 jumper wires to those 2 terminals and had my pump running on a battery try that but remember its a d/c pump so it pumps eaither way just no fuel will come out one way and remember to see if you have power on the car terminal the car has to crank to trigger the fuel pump!

 

well its not a tune up i already went threw all that it would knock super loud at 1000 rpms so i had my dad a mechanic for 30+ years look at it and he said its advanced ignition knock which means the ignition ignites before it should causing the knock and he said it could be anything now i think its the computer low on power because my alternators going bad but we'll see!