duffsr

Good morning,

I've been working with an infrequent and seemingly random misfire on cylinder 2 on my 05 with 42k miles. The car never smokes or burns oil. I ruled out plugs and coils, and the car seemed to run well with a seemingly random hesitation. I pulled the injectors and had them serviced, the shop found that the cylinder 2 injector was faulty. After replacement of the injector the car is running very smoothly, seemingly fixed the problem until the same misfire code appeared, always p0302.

I tested the compression this AM (forgot to go WOT if that matters), and got 210 psi across the board except 110 psi on cylinder 2. I'm trying to find a shop to do a leak down test at this point, but wondered if anyone might have insight as to what may likely be damaged after running with a faulty injector.

Many thanks in advance,
Reid

windhund116

AFAIK, a plugged injector should not damage the cylinder it is attached to.

jkelley

I had the exact same situation as you (basically speaking). I would get a cyl 3 misfire code every now and then (think every ~2,000 miles). I would clear it, and it would go away, then come back in 1,000-2,000 miles again. Always cyl 3. I did a compression test myself and got 220-220-120-220. Turned out it was a burnt valve. There were no indications as to why this happened (valve adjustments done regularly and this was a non-DBW with the notorious tightening of clearances to 0).

I sent my injectors off to be flow tested and ultrasonic cleaned. #3 came back pretty bad, the other were fine.

So, I have no conclusive proof, but my situation was the same as yours basically.

Maybe the low fuel to that cylinder causes the AF ratio to be high in the one cylinder and it can somehow affect something on the valve seat? Or maybe the injector isn't able to close all the way so fuel leaks out of it overnight and cause some startup damage to a valve seat? I dunno. I'm not a mechanic. But I fixed my head and my injector(s) and all is well. 240 psi on all cylinders now (the whole head was done, by jordan, not just the one set of valves).

duffsr

That's what my thinking was, but as seen below, i imagine the conditions of running a non-firing cylinder can lead to damage and buildup that the fuel normally treats. Thanks for the reply.

Sounds spot on to the scenario I have. I am hoping there is a good shop here in N. Alabama that can do the head. Much appreciated on the reply.

jkelley

If you're in northern Alabama you need to make the drive to Jordan in Christiana, TN. It might be a bit further of a drive than you were wanting but I can promise you won't get better results and it will be a very reasonable price.

bitslop

I'll chime in here to say that I just got back from driving quite a ways to have Jordan do the head on my 06 s2k, due to burnt valves. I highly recommend him as well - great job, reasonable price, and very accommodating.

duffsr

Right on. Christiana is not too far from here at all. Is he on this forum or could you PM me his info if possible? Thanks! Reid

bitslop

His username is MM3Kwolik, just send him a PM and I'm sure he'll get everything all set up. Good luck!

s2000Junky

It absolutley can if its running to lean from poor injector flow. Just depends on how severe it is. 110 Compression is vertually a dead cylinder. I hope in the case of the OP that its valve related and not fried piston rings, any of which can be destroyed from running too lean an A/F.

jkelley

The strange thing is that I noticed very minimal (if any) difference in the way my motor actually ran with that low compression in #3 versus the refreshed head that test at 240 psi all around.