What up guys I have a question and I'm sure my buddies here could help, I have an 88 iroc 5.7ltr. Just this after noon I went to start it and it wouldn't stay on, only way it stood on is if I kept my foot on the gas. I opened up the hood and started it checking for any vacuum leaks and such, I noticed the grommet for the PVC valve was torn so I replaced it, I tried turning it on but it did the same thing it wouldn't stay on. So I replaced the PVC valve with a new one and again it wouldn't stay on. I tried disconnecting the hose to the PVC valve and tried to turn it on and yes it turned on without me giving it gas. So I'm stumped cause now it only stays on when the hose is not connected. Another thing I tried was connecting the PVC valve just to the hose without connecting it to the valve cover, and it did the same thing, wont stay on. So the only way it stays on is with the hose not connected. I'm going to trouble shoot it some more right now in my garage, but if anyone has any idea or suggestions on what it could be or what I could try and check please let me know. This is the only car I have right now so i depend on it a lot. Any help will be appreciated. Thanks in advance. Ps my email is saldav420@gmail.com it would probably be easier to email me since I will be in my garage and have no computer there. Thanks again.

 

Umm, try replacing the pcv valve or try cleaning it out good with some carb cleaner spray, the chech bearing or whatever it is inside the pcv is frozen up, like i said try cleaning it up first an see what that does or replace it. I really have never heard of the car not staying running because of a bad pcv, i dunno. Could be also maybe the carb choke isnt working properly ?

 

Idk If you read the entire thread but I did mentioned I replaced the pvc valve with a new one and put a new gromet. My iroc is a tpi so I have no carb.

 

Are you trying to say the engine won't stay running after it starts up?

 

I crank it but I have to keep my foot on gas so I'd stay running. Once I let of gas it turns off. Only way it stays on is when I disconect the hose from the pvc valve.

 

if I'm under standing this correctly you are creative a vacuum leak ? if thats the case the throttle blades may be adjusted to far closed or the iac isn't moving out to 160 steps. Wiring issue, carbon build up in the iac passage, faulty ecm.

 

Engine appears to be WAY rich; holding your foot on the pedal or leaving the PCV hose off lets in extra air .(nothing to do with the valve itself , just the hose as a big air leak into the engine )

Ditto the starting;
if you have to have the throttle open to start it has too much fuel because with your foot on the pedal while cranking over the fuel supply is cut off.

 

 

Ok just noticed the single wire o2 sensor was torn. I spliced it and yet its doing the same thing. Is there a way to test the wire comming from the harness to the o2sensor? Damn thing got tangled on the steering column. Smh!

 

A problem but not your current problem.O2 sensor is only in operation after the engine has warmed up.

Have you pulled the engine codes to see if any faults showing ????

 

No codes

 

But wouldn't I have to drive it for a while for codes to show?

 

What would cause it to run rich all of a sudden?

 

No

Leaking injectors

 

Injectors are all new

 

Pull off the vac hose to the FPR on the pass side rear of plenum and see if it has any fuel / fuel smell in it.
If the diaphragm in the reg is split then fuel can be pushed straight into the intake any time the pump is running

With the hose disconnected plug it very tight and see if the engine will run.

 

What's the FPR?

 

FPR=fuel pressure regulator

 

Ok ya I'll check that out

 

Just because you have a new part doesn't mean squat. Thats were watching a fuel pressure gauge comes into play. It could even be the ninth injector stuck open.

 

I don't understand now, I connected the hose to the pvc this morning to show my neighbor that it wouldn't turn on after explaining everything it was doing. I go and turn the key and it turns on like normal, as if their was no issue at all. I test drove it, turned it of and on like 10 times drove it again, paked it in the garage, and came back out a couple hours later to read any codes (no codes) turned the key and it fired right up no problem. I'm confused now everything is running fine as if some little people came last night and fixed it durring my sleep. ???????

 

Your welcome I waved my magic wand

 

Thanks I know I could always count on you lol, but you know who I'm calling on if the fairy dust wares off. Lmao! To be continued! Hope not but we will see.

Thanks to all for the help! I'LL BE BAACK!

 

Does the ninth injector have to be connected, or could it be bypass. What's the purpose of the ninth injector? On a 88 iroc camaro 5.7 ltr tpi

 

The ninth injector aids with cold starting enrichment.

https://www.thirdgen.org/forums/tpi/...rt-issues.html
http://www.ebay.com/itm/Chevy-TPI-SBC-Cold-Start-9th-Injector-Block-Off-Delete-Kit-/310724821775?pt=Motors_Car_Truck_Parts_Accessories&hash=item4858a4830f&vxp=mtr

 

If the ninth injector is stuck open would the bypass eliminate that problem?

 

Just an hour ago I drove to the store the car turned on with no problem, but when I was done shopping the car wouldn't start. Note; the ninth injector hasn't been connected for the last week. Had to crank it and give it gas a few times before it stood on. Does that have something to do with the ninth injector not being connected, or is this another proplem?

 

Its hard to say if its the ninth injector, if the ninth injector hard line is loosened up and the hold down for the ninth Injector is removed with the fuel pump primed engine off you could see if the injectors is leaking.

 

How could I tell if any of the injectors are leaking? I just got home and put the car in th garage turned it off then turned it back on and noticed black smoke comming out of exhaust, I'm stressed out now cause idk what's going on. I really appreciate all the help you are giving me, and for taking your time to reply to my questions.

 

Its a little had to find leaking injectors in the vehicle. What you can do is either prime the fuel pump several times or apply power to the G port of the aldl connecter if equipped. You will have to start pulling spark plugs looking for wet plugs. If you even find one thats wet replace all eight injectors. Its not worth your money to have them cleaned and flow tested for the labor involved to replace them. Southbay fuel injectors has a great deal on the bosh 3's

 

So what's the deal with the black smoke?

 

Unburned fuel

 

Putting your foot on the accel pedal while cranking over shuts off the injectors ( if they are not leaking ) so you get no "gas"
You can't give a EFI engine "GAS" ; when you put your foot on the pedal you are giving it AIR .
If that is what it takes to start the engine then the engine is way too rich even when you are cranking it over.

The engine is running RICH , very rich.

 

How do I fix the rich problem, what is causing it to run rich?

 

Possiable causes, leaking injectors, bad ecm, maf, cts, exhausted leak bye o2 sensor, leaking fpr, faulty tps or set to high. take a pick. Without doing some diagnostic having a scanner, using tuner pro or doing the above suggested testing only god knows.

 

I scaned for codes and code 33 and 36 come out

 

Start with the maf High

 

Maf high? I don't understand. What do I do?

 

https://www.thirdgen.org/forums/tpi/...-pls-help.html
http://chevythunder.com/maf_code_36.htm

 

What is Aldl? I'm very new to this.
Code 33 and 36 have been on for months already. I just don't understand why all of a sudden I'm having all the above problems.

 

ALDL= Assembly Line Diagnostic Link, Located on the drivers side under the dash rh side of the steering wheel.

 

I live in California and its 1:00am. This is the only car I have and the economy is no good right now especially with me not working I need the most help I could get from this forum. I really appreciate everyone's responses, but it would be a blessing from god if someone that could truly help me one on one either through email or phone. My email is saldav420@gmail.com. my # Is area code (619) 742-5149
I'm not working at the moment full time I do side jobs, body work, welding fabs etc. But lately its been dead. I drive my wife to the trolley for her to work. So I'm free in the mornings, afternoon and night. Any help would be greatly appreciated. Thanks and god bless.

 

Is that where I connect th scanner too?

 

Should have mentioned that little fact up front
Having a code up means the computer is telling you there is a problem with the engine and you are supposed to fix it ;or at least investigate if it is important.
Given a DTC 33 is a MAF fault and the MAF signal to the computer helps set the amount of fuel supplied to the engine ........

The fault diagnosis chart has been put up for you.Work through it to identify what / why that code is present

Yes

 

With that said I had this motor rebuilt eight months ago, and after they gave it back those codes were already there. Is that something that should be covered under their warranty?

 

It would not be covered bye the engine installer unless its found they damaged your wiring harness or dropped the maf.

 

@tuned performance. Code 33 and 36 have been on for a while now, but car ran fine I guess in my mind. This morning I took the wife to work, and car turned on fine no problems, but when I parked it and tried to turn it on it kept doing the same sh@t witch is stated above(wont turn on). I rescaned the car and now it has code 43 plus the other two mentioned above. What is going on with my car, what is code 43? What do I do....

 

Since your running rich hard start is inconsistent it shrouds like a possiable ecm issue.
Folling this trouble tree for the code 43 might be easier than going though the maf trouble shooting. you should also make sure the ground wires are secure behind the passenger side cylinder head.
http://chevythunder.com/maf_esc_module_code_43.htm

 

Ok I replaced the maf sensor, and all codes are gone. It ran fine for a few days butt now its doing the same thing it doesn't stay on. Only way it stays on is if I keep my foot on the gas. Another thing I did was remove the throtle body spacer that was useless anyways. I adjusted the tps to 0.54. Another thing I didn't mention before was a small leak on top of fuel tank since I opened up a hatch to replace fuel pump a couple months back. Its a tiny pin hole that I thought I fixed but I could smell fuel from the back anyways. Someone mentioned I need to connect more ground wires to the motor. But idk if that's correct. I also noticed that previous owner instead of sodering wires that go to fuel pump relay, they were only spliced together. All wires from harness to fuel pump relay are spliced. Also noticed that wires to tps sensor are also spliced. I really need help with this car I've put to much $ into rebuilding the motor and tranny. I've been researching like a maniac and I thought I fixed the problem with the new maf sensor but I guess not. Please any other suggestions will be appreciated. Again thanks in advanced and god bless.

 

Ok I replaced the maf sensor, and all codes are gone. It ran fine for a few days butt now its doing the same thing it doesn't stay on. Only way it stays on is if I keep my foot on the gas. Another thing I did was remove the throtle body spacer that was useless anyways. I adjusted the tps to 0.54. Another thing I didn't mention before was a small leak on top of fuel tank since I opened up a hatch to replace fuel pump a couple months back. Its a tiny pin hole that I thought I fixed but I could smell fuel from the back anyways. Someone mentioned I need to connect more ground wires to the motor. But idk if that's correct. I also noticed that previous owner instead of sodering wires that go to fuel pump relay, they were only spliced together. All wires from harness to fuel pump relay are spliced. Also noticed that wires to tps sensor are also spliced. I really need help with this car I've put to much $ into rebuilding the motor and tranny. I've been researching like a maniac and I thought I fixed the problem with the new maf sensor but I guess not. Please any other suggestions will be appreciated. Again thanks in advanced and god bless.