Bad valve springs/rocker arms/ etc...??? - SRT Forums

REDSRT19 · 10-16-2009, 10:12 AM

Ok i have been chasing down a missfire problem and have tried just about everything. The motor itself is stock, top and bottom, no cams or anything. Have there been anycases of stock valve springs going bad or any of the valvetrain for that matter that could make an intermitted missfire. Any info would be greatly appreciated. Thanks

A list of the things i have tried:

Replaced plugs
Replaced plug wires
Replaced coil pack
Boost leak tested S2 injectors
Replaced S2 bottom injector O-rings
Reanstalled Stock injectors (properly stored for such an occasion)
Boost leak tested stock injectors
Reinstalled stock Map sensor (properly stored for such an occasion)
Reinstalled stock Tip sensor (properly stored for such an occasion)
Boost leak tested intake manifold with soapy water
Boost leak tested intake manifold with carb cleaner
Checked all grounds that i know of
Wiggeled and moved all wires and harnesses
Removed and cleand all three connectors for PCM
Took off old tape, cleaned, applied new tape to the three PCM connectors
Removed, cleaned, reinstalled PCM
Fuel pressure test (Checked out)
Replaced intake manifold gasket
Replaced up stream o2 sensor

This is on an 05 srt.

a853rox · 10-16-2009, 12:58 PM

Just a few things...

What are your plugs gapped to? Try .032-.035"
I don't see anything about mileage, how many miles on the car?
Have you replaced the fuel filter? What brand and type of gas do you usually fill up with?
How/when do you get your missfiring issues?

lyncoo · 10-16-2009, 01:15 PM

add a mod list to please

REDSRT19 · 10-16-2009, 02:40 PM

Quote: Originally Posted by a853rox

Just a few things...

What are your plugs gapped to? Try .032-.035"
I don't see anything about mileage, how many miles on the car?
Have you replaced the fuel filter? What brand and type of gas do you usually fill up with?
How/when do you get your missfiring issues?

-Plugs are gapped at 0.037. im only putting out 17psi right now.

-car has 42,xxx miles. Bought it with 15,523 and i am the second owner.

-No i have not. I only fill up at Shell, and Marthon. 93 oct only, never under.

-It happens whenever it wants too. Sometimes at cold start, opperating temp, in between. But then some times it wont. it has a mind of its own. I know that the car runs rich at idle from factory and that there is a slight feel of a missfire but thats not what im talking about. it is only at idel that it missfires( at least thats what the scan gauge shows while driving, and idle).

Here is a mod list from the top of my head. have to go home and look around to see what else ive done ( sooo much its hard to remember). Tried to put it in my sig but it wont show up.

Got the sig to work now. lol.

E1 turbo/ AEM CAI/ CTI FMIC/ Champion plugs/ MSD wires/ S2 injectors/ S2 WG/ S2 MAP/ S2 TIP/ Mpx o2 pipe/ QTP 3inch DP (catless) w/e-cutout/ Mopar CBE/ JMB hardpipes/ Tial BOV/ AGP Catch can/ P-WERKS S2 trans/ SCT/ Mpx 62mm TB/ BC COs/ Prothayne bushing kit/ stoptech rotors/ hawk pads/ P-WERKS rear strut bar/ Vibrant front strut bar/ AEM wb/ AEM oil preasure/ Aeroforce gauge/

a853rox · 10-16-2009, 10:45 PM

Very nice mod list man.

I would initially still point to the gap on your plugs (and maybe the plugs themselves, the champions are ok, but can wear out fast) Try gapping them at .034" and see what you get. If you could, while you have the plugs out, take a pic and post up what the electrodes look like.

REDSRT19 · 10-18-2009, 07:27 PM

Quote: Originally Posted by a853rox

Very nice mod list man.

I would initially still point to the gap on your plugs (and maybe the plugs themselves, the champions are ok, but can wear out fast) Try gapping them at .034" and see what you get. If you could, while you have the plugs out, take a pic and post up what the electrodes look like.

Thanks

Well i replaced the plugs for the reason of the missfire. The old plugs were factory and therefore at.050. The new plugs didnt make a difference at that gap or at .037.

After all that you have read, you know what i have done, and i have become stumpped and am wondering if it has something to do with the valvetrain. I have searched on the forums to see if anyone has had a problem with the stock valves, valvesprings, rockerarms, cams, etc... and have come up empty. Thus making me want to rule it out but i want to make sure.

Also wondering if the whole seafoam thing might help. You have any experience with that?

REDSRT19 · 10-20-2009, 01:41 PM

Bump!!!

raul-01 · 10-20-2009, 03:50 PM

Get rid of the champion plugs and try some NGK V-Power 4306. Gap them at .035 and report back. A full set is under $10. Its worth a try. The stock hampion plugs are not meant to be gapped that low.

REDSRT19 · 10-21-2009, 01:11 AM

Quote: Originally Posted by raul-01

Get rid of the champion plugs and try some NGK V-Power 4306. Gap them at .035 and report back. A full set is under $10. Its worth a try. The stock hampion plugs are not meant to be gapped that low.

HAHA. I actually just did that yesterday with the exception that i had them at .037, then at .033. missfire still there.

What does it cost to get the PCM looked at with a DRB3 by the dealer? I havent had that done yet.

nutz · 10-21-2009, 04:01 AM

i seriously doubt the valve train has anything to do with it

m_dunnie · 10-21-2009, 05:40 AM

I had an intermittent misfire several years ago. Ready.......one bad fuel injector.

REDSRT19 · 10-21-2009, 09:24 AM

Quote: Originally Posted by nutz

i seriously doubt the valve train has anything to do with it

And thats what i was thinking because i couldnt find anything on the forums about a stock valvetrain going bad. But i had to make sure.

REDSRT19 · 10-21-2009, 09:27 AM

Quote: Originally Posted by m_dunnie

I had an intermittent misfire several years ago. Ready.......one bad fuel injector.

I changed my S2 injectors out and put the stock ones back in. Still had a missfire. It hapens in cyl #4 most of the time but sometimes might spread and have all the cylinders misfire randomly.

nutz · 10-21-2009, 04:54 PM

Quote: Originally Posted by REDSRT19

And thats what i was thinking because i couldnt find anything on the forums about a stock valvetrain going bad. But i had to make sure.

I woulda said try to change to a new o2 but looks like you tried that, whats your WB reading look like

juppes_Srt-4 · 10-21-2009, 04:55 PM

could be something fuel related seeing as cylinder 4 is the farthest away?
i dunno good luck with it man i had to chase down a misfire as well a few months ago mine was the FPR..