96 Legacy STILL not running properly

[wentz912]

Car is a 96 Legacy Brighton, 5MT, Phase one, Single Port EJ22E, currently 141k miles on the whole package.

 

So, I've been trying to clear up a miss/stumble that my car has had since I've owned it. Never got to drive it before the repairs I did to it, so I cannot speak for it's condition before hand.

 

Anyhow, when I got the car it needed a new passenger side cam and pulley because the PO had failed to fully tighten the bolt that mounts the pulley to the cam, and the keyway had been torn up.

 

Also threw a timing kit,including water pump, at it while I was in there, just because.

 

The issue I am having is that after warming up the car has a miss/stumble at anything other than WOT. Some days are worse than others, with no real pattern to the malfunction that I'm able to discern.

 

I occasionally get a code/CEL for misfires on cylinders two and three.

 

When plugged into GD's live scanner, the timing showed as being correct, with no other codes than the ones mentioned above.

 

BUT the fuel trim rates are all kinds of crazy. I think the worst we saw while looking at it was -27 while at idle. It would eventually catch up when holding her to WOT, then go back to super crappy as soon as you tried to hold it mid throttle or at idle.

 

Along with what I mentioned above, I have replace the O2 sensor with a new NTK unit, the coil pack with a used JY unit, new NGK plugs and wires, the Crank Position sensor with a good used one off an engine that ran fine, and even went so far as to replace all four injectors with the ones off the known good engine. None of these parts have helped my problem, or made it worse for that matter.

 

 

 

So, at this point, I'm out of ideas and damn near out of patience. I know it's probably something really stupid that is holding me up, but I can't for the life of me figure out what it is.

Edited January 28, 2013 by wentz912

[Fairtax4me]

Timing shown on a scanner would be ignition timing, but that doesn't indicate if the cam timing is correct. If you've had GD check the cam timing we can rest assured its fine. I chased a multiple cylinder warm engine misfire for three days only to find out the drivers cam was off by one tooth. :Facepalm: Only happened once the engine warmed up, and would go away under heavy throttle at mid range and higher RPM.

 

Fuel trims that far negative mean its runnin way rich, or it thinks its way rich. And it's pulling fuel to compensate. This could just be due to unburned fuel in the exhaust though.

What kind of spark plugs did you put in? Did you set the gap accordingly?

Have you checked engine vacuum? Steady 19-20" at idle?

Checked compression?

 

Is this a 2.2 or 2.5? If 2.5, have you checked valve lash?

[wentz912]

Engine is a EJ22.

 

Have not yet checked compression as I have thus far been convinced that it is a sensor/electrical component issue.

 

Plugs were NGKs, left them gapped at the recommended distance that they came out of the box at.

 

How does one check engine vacuum?

 

I will double check my cam timing tomorrow, although with how much I fought it getting the thing installed, I'm 99.999999999999% certain it is correct.

[GeneralDisorder]

I would try a known good MAF.

 

GD

[wentz912]

Have any spares around the shop, GD? I'm going to go through the other stuff mentioned here in this thread, just to check MORE stuff off the list. I hate throwing parts at something hoping that it will fix it.

[Fairtax4me]

Plugs were NGKs, left them gapped at the recommended distance that they came out of the box at.

What kind though? Copper? Platinum? Iridium? Gaps make a difference on copper plugs especially. Usually the iridiums state not to re-gap.

 

Vacuum is checked with a vacuum gauge hooked up to one of the ports on the intake. You could also T off of the hoses for the FPR or MAP sensor if it has it. This may also tell you if there are any leaks, but check the general condition of all the vacuum hoses if you haven't already.

 

MAF sensor would certainly cause some problems. You could test it by unplugging it to force the ECU into fail safe. Swapping is easy too if you have a known good spare. Also make sure there isn't oil or dirt all over the sensor element.

 

Another sensor that causes problems is the knock sensor. Check it for cracks in the housing, corrosion. One of those things that makes a big difference but might never set a code.

Edited January 28, 2013 by Fairtax4me

[MilesFox]

I would try a known good MAF.

 

GD

 

MY buddy's frankenmotor soob was acting like this with #2 misfires. We did try and swap a known good MAF from the trashwagon and it seemed to cure it for about 10 minutes until you could feel the misfire off idle while accelerating. He is suspecting the injector is faulty. But also he swears that it goes away when running chevron techron in the fuel.

[wentz912]

well, diligence still conquers all apparently. Drivers side was off by one tooth. All fixed now.

 

Can't believe how much power these have when they are running properly!

 

Thanks to all that assisted!

[Fairtax4me]

well, diligence still conquers all apparently. Drivers side was off by one tooth. All fixed now.

 

Can't believe how much power these have when they are running properly!

 

Thanks to all that assisted!

 

Makes a big friggen difference doesn't it, that one tooth? :-p