Pearcy91CAMARO

Ran great for 2 months. Stopped to get gas started running like crap. It idles just fine, but when you give it gas it runs rough, won't hold steady Rpms. Only backfires when driving or giving it gas. thought it was bad gas but I already ran 3 full tanks since then from better gas station, new fuel filter good fuel pressure. New spark plugs new wires new distributor new rotor and new ECM. It has random miss and back fire. Could it be the ICM? Or pick up coil? Any ideas would be great. Thank you. It is a 5 speed.

Stewie

A bad ICM can cause all kinds of crazy problems. Coils tend to go bad faster than they should because the stock placement gets them very hot. I've got a similar problem and, based on some history, for my car, I'm sure it's in the throttle body. Probably, needs to be taken off and cleaned.

But, in your case, you could pull out the ICM and have it checked for free at your local auto parts store. Just be sure to tell then to check it several times so it heats up a bit.

You could also start disconnecting things one at a time and driving to figure out which part is bad. Things like IAC, CTS, TPS, etc. It's faster and less expensive than putting on a bunch of new parts (been there, done that). Please keep us updated on your progress. If you think of any other symptoms, post those.

Pearcy91CAMARO

Good news and bad news, I bought a new distributor and it's not as bad now, I pulled the plugs and they were nasty, cleaned and put back in. Slowly getting better. If I buy a coil what brand should I get? I've noticed the "house" brands aren't really that good. Thank you for the advice

Pearcy91CAMARO

Well I said it was slowing getting better, but this morning took it for a drive and it got worse. Needless to say I spent most of thanksgiving day workin on the car. I'm starting to think its a lazy fuel pump. I tore off the intake cleaned it spotless cleaned everything spotless still doing the same. Very rough acceleration and a back fire every time I shift.

NCC-2569

iTrader: (1)

Have you bought a remanufactured distributor or just a bare one and put some parts on it?
A reman one would be tested and reduce your number of possible faulty parts for now.
In that case you wouldn't have to look for a new ICM or coil.

Either way, get a timing light, disconnect the EST plug and check your timing.
If the light flickers irregularly -> faulty ignition component (ICM/coil).

Fouled plugs and back-/misfires sound like bad timing or too much fuel.
You can measure the resistance of your injector coils, but you'll need to remove the top half of your plenum to get to the injectors.
Ideally the injectors would be warm and the measured values will roughly indicate the state your injectors are in.

Pearcy91CAMARO

Timing is spot on, gonna check fuel pressure and If fuel pressure is good then pulling injectors out and testing them.

RBob

iTrader: (1)

If they are still the original injectors, be sure to have a new set to install once those are removed. No sense needing to go in there twice.

RBob.

Pearcy91CAMARO

I hate to say it but its my fuel regulator or check valve in my fuel pump. I don't know how I let that slip my mind but I hooked up the fuel pressure gauge and it had 45 psi, then dropped to 10 psi in under 30 seconds. Closed the return line it went up to 80 psi then back to 10 is again under 30 seconds.should I replace both to be safe? Or could it be something else that I'm forgetting.

Stewie

Probably the FPR. They don't last forever. Rock Auto had the best price when my FPR went bad.

If your injectors are original, they have a well deserved reputation for being crap. If you decide to replace, Southbay has good prices for high quality new and refurbished injectors. If you tell them you are a Thirdgen Forum member, they give an extra discount. Calling them is best because they have very knowledgeable sales staff.

I changed the original fuel injectors at the same time I replaced the FPR. Injectors were going bad. I was lucky, very lucky to get over 100,000 miles out of them.

Pearcy91CAMARO

i will check on that, thank you, i should be lucky my car is still running with original FPR and incjectors seeing as how theres 240,xxx miles on the car. only thing new is a few gaskets and water pump.. and now the new parts ive been putting on there

Pearcy91CAMARO

I've tried everything, my car won't do over 45 and my spark plugs keep going out. What can make the plugs keep fouling out? It don't use oil.

NCC-2569

iTrader: (1)

Do you know someone who can hook your car up to a computer?
Would be interesting to see the injector pulse times.
It's strange that you don't get a SES light for a rich fuel mixture.
Do you have a decent pic of one of your foul plugs for us?

Maverick H1L

iTrader: (8)

Pull the vacuum hose off of the FPR and let the fuel pump run through a prime cycle. There will either be fuel coming out or there won't. No fuel means new injectors and fuel coming out means a new FPR diaphragm.

Pearcy91CAMARO

Update. New fuel pump in new plugs. Runs worse then before.got a meter and checked the ohms on my injectors, some was at 7 ohms and some were 5 ohms so its gonna be a little while before I replace them. I may get some ford 2.8 injectors. I want better response. And cheap.

southbay08

Well, your injectors are definitely done. When you are ready, give us a shout...we'll be more than happy to help you. Don't forget to let us know that you're a tgo member...
you will receive 10% off.

LarryD

Don't forget to check your IAC.... They don't last forever either and can stick easily.. My car is over 400,000 mi and I have had to replace mine twice...

Just an added note.. I have used a guy out of Idaho called Mister Injector to clean, repair and test my injectors.. Had him do my 3.1 injectors two years ago with very good results.. Just had him do my 3.4 injectors for my 3.1 to 3.4 swap... Reasonable price, you get test results with your cleaned and repaired injectors and quick turnaround..

LarryD

Oh, and one more thing to check... In my 400,000 miles I have had to replace 3 electronic modules in the distributor... They will often go intermittent before they fail completely (usually as they heat up).. That means they will shut off spark briefly, it misses and the unburned fuel can build up in the exhaust and backfire...

Pearcy91CAMARO

The back fires gone. New fuel pump took care of that. Iac is new along with the pickup coil and the part that goes under distributor. New filters new plugs new wires new temp sensor. Thanks you tho

Pearcy91CAMARO

The back fires gone. New fuel pump took care of that. Iac is new along with the pickup coil and the part that goes under distributor. New filters new plugs new wires new temp sensor. Thanks you tho

maroe624

Just go to the junkyard and ****** some injectors off some 92_98 mustangs. They are the f1ze b4cb4c Jus finished putting these into my 3.1.. You just have to use the orings from your old injectors cause the ford ones are thinner.. Great accelaration throttle response. My v6 sounds beefier too.

Pearcy91CAMARO

New injectors from south bay injectors. They work great. Car runs great when its sitting still. But since I got the timing dead on the mark ipwhen try to drive it spits cusses and has a fit. Is there a way to check the coil with a multimeter? Could that be the problem? Also when setting the timing I had no ses light on. But when I got done and had everything tight unhooked battery for a while hooked it back up and idled at 1000 rpm great until I put a load on it

LarryD

One quick way to check the coil is to start it up with hood open.. Turn out the lights as dark as possible.. Look for electrical arching in and around the coil... You might have to light it with a flashlight and then quickly turn out the flashlight while you are looking right at the coil.. Can be hard to find in the dark unless it is really arching...

Pearcy91CAMARO

I checked for that. If the coil is to weak will it idle fine but mess up when its under load

RBob

iTrader: (1)

Good deal on the injectors. As for the SES not being on while setting the timing, that may be a problem. First check that the SES is operating properly, quick test:

At key-on, engine-off the SES should turn on briefly, blink off, then turn on solid. Can repeat the test after 10 seconds of key-off.

This test must pass before any other trouble shooting is done.

Once the SES does the blink, open the EST/BYPASS connector and start the engine. The SES must be on, if not then the ICM in the distributor may be bad. Or, it wasn't the EST/BYPASS connector that was opened.

Once that is figured out and the SES does turn on, re-check the distributor base timing with the EST/BYPASS open. Note that this will also set code 42, but ignore it.

RBob.

Pearcy91CAMARO

Finally got the timing dead on. Now it cuts in and out if I don't pump the gas pedal and feather the trhottle . any ideas? Why do I have to pump the gas pedal to keep it driving and rough idling now

Pearcy91CAMARO

Love your injectors. Helped a lot fair price and got here the next day

southbay08

Thanks for the feedback. Happy things worked out