Not running right, checked compression

[The Machine]

Thanks again Rick.

I've swapped the plugs & haven't fired it yet.
Here is the old/new plugs (I think I'll save'm):

I wonder where the problem is :wink:

So I should swap the #3 injector with one from another cylinder?

If a cam lobe went I should have noticed the metal particles stuck to the magnetic drain plug when I put some fresh Syntec after doing my valve springs. I should have done as you suggested at that time, and run it to check the operation of the rockers. Hindsight.

Thnx again!
Jimmy

 

[Quick6'n'-K.C.]

Sometimes it takes thousands of miles to wipe a cam lobe.

Its either a stuck open injector.... Put a fuel pressure gauge on the car, build pressure and turn key off.. If the fuel bleeds off real fast, it could be that #3 injector or a unrelated issue with the check valve in the fuel pump.

You could, prime pump, then crimp both rubber lines to hold static pressure on the rail. Check to see if it holds pressure, or bleeds down.

Or either a bad cam lobe- Pull the valve cover and inspect the #3 exhaust lobe while turning the motor over to see if the rocker is moving.

I would just pull the valve cover off, would almost be easier than pulling the injectors out if they have never been out before.

Run your finger around the injector, are you sure its not burned from the EGR and causing the injector to fail?
BW

 

[The Machine]

Thanks Guys, I'll try to reply while you're still awake.

They are 50# Delphis, with about 10K miles on them. I just replaced the pump, and have a rail mounted gauge. Ever since I put the gauge & Delphis on, along with a billet adjustable FPR, I've had fuel pressure bleed down. I've never timed it, but I'd say pressure lasts no more than 30 minutes after shut off. Course I had no way of seeing it before that point.

Is it possible that injector had issues, and when I reinstalled my EGR cover, the heat going towards that injector increased, & finished it off?

As for taking the valve cover back off again, why do you guys hate me?
Just kidding....

Thnx again,
Jimmy

 

[TurboBuRick]

See, What I tell ya. Now you have to figure out if its a injector or a cam lobe.

Do what Quick6'n'-K.C. is saying. Good Luck

 

[Quick6'n'-K.C.]

Cam lobe...

NOW DO IT WITHOUT LIFTING THE HOOD

Just kidding :smile:

Well, with that low of mileage, and it taking that long to bleed down...

Could also be a bad injector wiring harness grounding out causing the injector to stay static....
Try a search on what would cause the injector to stay static if the harness was pinched..
I dont know the answer to that.

BW

 

[The Machine]

I do have that sthetascope from Napa. I can hear the injectors clicking, I'll recheck that first. Then I'll loosen the rail & see if I can swap 3 & 5. Then I'll do as I'm told :biggrin: and see if 5 fouls.

If 5 doesn't foul, I'll pull the vavle cover back off...moaning & groaning......

Prechiate it guys!
Jimmy

 

[Quick6'n'-K.C.]

I do have that sthetascope from Napa. I can hear the injectors clicking, I'll recheck that first. Then I'll loosen the rail & see if I can swap 3 & 5. Then I'll do as I'm told :biggrin: and see if 5 fouls.

If 5 doesn't foul, I'll pull the vavle cover back off...moaning & groaning......

Prechiate it guys!
Jimmy

But if #3 fouls again, it could be the injector harness or something else in that cylinder...
At least its narrowed down..

BW

 

[The Machine]

Hey Bryan, can I swap the 5 & 3 FI harness connectors first? Will that work, or cause some problem? I kinda looked at it earlier, it looks good to me.

Thnx,
Jimmy

 

[Jerryl]

ENcountered a very similar issue .........

I had a similar issue with #6 - Was always wet.

After changing the injector harness, plugs, cable, Coilpack, module, switching injectors (if you ever worked on a HOT Air, you would appreciate the work doing this), verifying cam lobe, compression, leakdown, springs, lifters, etc ........ it turned out to be a bad ECM. Ended up changing that 2 times as well, since I purchased one from AutoClone. Look at sig for ECM source.

PS
Mine ran on 5 cylinders (On and Off) and I was changing the oil every 5-miles while trying to figure it out, just to make sure I did not take out my new motor.

 

[TurboBuRick]

Hey Bryan, can I swap the 5 & 3 FI harness connectors first? Will that work, or cause some problem? I kinda looked at it earlier, it looks good to me.

Thnx,
Jimmy

No you can't do that. That woud be like switching a spark plug wire.

 

[The Machine]

Thanks Jerry, Maybe I'll swap ecu for the hellofit.

Thanks again Rick, I thought maybe it was actually a bank to bank system.

Will report back once I've switched the injectors/ecu.

Thnx again,
Jimmy

 

[The Machine]

Swapped the ECU with a mystery spare. Reused my chip for #50 injectors.

Same skipping / missing

Next I'll either swap #3 & #5 injectors, or I'll take them all to an injection shop up the road who'll clean & flow them for $80 total.

I found #50 MSD / Delphi injectors on the web for right at $50, so I'm wondering if I should just buy one of those. But then maybe it wouldn't match my set. I guess a flow sheet would be nice right about now.

I also unhooked my ECU power wire after taking it for a spin, to see if I still bleed down from an injector staying grounded. It was just an idea.

Getting closer....

Thnx again,
Jimmy

 

[Jerryl]

Swapped the ECU with a mystery spare. Reused my chip for #50 injectors.
Same skipping / missing

Jimmy,

It may be nice to list a summary of the issue and all the things you have changed and updated. This will allow a birds eye view of what the possible cause may be.

Was the "mystery ECM" a known good one?
Did you try changing the chip?

 

[TurboBuRick]

Pick up a new injector. Do you have MSD's now. Get the same one you have. You can switch the injectors if you want to know for sure but I would bet thats your problem.

You have one black plug. You checked compression. You changed coil, module, wires and ECM. There is nothing else left. Get a new injector and put this behind you.

 

[The Machine]

Thanks again for your time & brain power guys.

I had the injectors cleaned, flowed, stressed, and checked for leak down. All I can say is damn, that wasn't it.

The guy who did it was in the 9s with a Buick GN years back, he said what you guys said, check the lobes on #3. Appearantly they are notorious for holding the lifter a bit crooked on that cylinder. My last Buick never had issues with that?

Oh well, lemme get this back together, & I'll check the rocker arm movement next.

I'd like to take the EGR off while I'm working right there, but I don't know if the Extender chip has active EGR functions or not. If it cause problems with the injector, and the injector harness due to heat & leaks, why not take it off? I have a block off plate, and vacuum caps.

Thank again guys,
Jimmy

 

[The Machine]

Jimmy,

It may be nice to list a summary of the issue and all the things you have changed and updated. This will allow a birds eye view of what the possible cause may be.

Was the "mystery ECM" a known good one?
Did you try changing the chip?

Jerry, car is still missing / skipping under normal acceleration, and sounds awful under heavy boost, with very low performance. Fouling # 3 plug.

What I've done so far:

I just took my injectors in & had them flowed & stressed, and checked for bleed down, they were fine. I've also done the spark plugs, sp wires, different coil & module, diff ECU (untested) reused same 50# chip, a new walbro pump & hotwire, crank sensor, cam sensor, O2 sensor, checked the normal grounds, new valve springs, pcv valve, oil & filter, disassembled & inspected the billet FPR, verified the accuracy of the rail mounted gauge, sprayed the injector harness with silicone, checked for shorting & added dielectric grease to the connectors, oh and I thru a stainless waterneck, stretch inter cooler & a te44c at it for good measures

Next I'll watch the little rocker arms go up and down, up & down, or not. :frown:

Then I'll choose a cam & get started on the last possible fix.

Thnx again for the help,
Jimmy

 

[ThikStik]

I supected cam after reading the first 3 posts. And after reading on....I really am saying cam. Symptoms can be amazingly all over the map from one guys bad cam to another. Compression doesnt tell the story either. It doesnt take much loss in lift to cause your symptoms. And if its just alittle worn, thats why there isnt alot of particles in motor.
If it is, Send a bill to the EPA for removing the zddp molecule from oil.
good luck

 

[The Machine]

Fixed?

Today I did a few things to the car & it seems to be fixed. Unfortunately I'm not sure what fixed it tho.

What I did:

Snugged up the battery terminals
Added conductive grease to the ECU power connector
Added conductive grease to the ECU pins
Snugged up the ignition module to maf translator adapter kit
Reseated the IAC connector (readings were 0 to 100??)
Repositioned # 3 & 5 fuel injector connectors (done this before)
Removed most of the factory tar from inside the cooling fan relay plugs
Revved the piss out of it

Personally & from what I've read, I think the tar in the fan relay plugs was conductive & sending voltage back down the signal wire to the ECU. Some other people have said removing the tar made their car run better, I just figured they were a bit off. Not sure why this would foul #3.

A little tuning & it should be formidable!

 

[mikestertwo]

head gasket??

 

[The Machine]

head gasket??

Thnx Mike, but see above, it seems to be fixed.