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What did I do?!

5K views 24 replies 9 participants last post by  cthcarter 
#1 ·
Alright so if you read my post in the exhaust section for WK2 you will see my problem will the valves in the exhaust rattling like crazy!

On the way to run some errands my engine light comes on. I'm worried sick about it at that point. I check my trinity and he shows P0303. Misfire in cylinder 3.

What the hell did we do that made this all happen? I am so worried right now as I don't have tons of money to fix stuff. The only thing I can think of is go back to the exhaust shop and have them put everything back on! There goes 400 dollars out the window...

Someone please help. This is driving me insane. I am freaking out
 
#2 ·
I read your post in the exhaust section I would make sure that shop did not remove valves . I would make sure. Many have removed them but I left mine just to avoid this type of headache and fuel mileage
 
#3 ·
I'm sure he didn't. I watched him do the whole thing. We talked about what to do with them and he said research it and then we will figure out what to do with them.
The valves are for sure there.
 
#4 ·
Not knowing exactly your setup maybe the install caused one or more of the valves to be in a bind and be stuck either open or shut, you can check their movement from underneath make sure they move freely
 
#5 ·
I was playing with them before we took her off the lift. No problems. They were moving fine and were not stuck. The rattle is horrible and I am getting the check engine light sound more and more. Guessing the cylinder is misfiring more now. I'm getting worried.
 
#6 ·
Do you know how to check your spark plugs? If so, pull the plugs on cyl. #3 and see what they look like? It'll be the second cylinder from the front on the drivers side.


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#8 ·
I do not know how put I will look it up and do it when I get home.

Maybe not the valves rattling? Maybe something else, missed weld ,something loose ,exhaust leak?
I checked for leaks and missed welds. Did not see anything.

Anyone else chime in? I really would like to get this sorted out.
 
#12 ·
STOP DRIVING THE CAR UNTIL YOU CHECK THE PLUGS ON CYL. 3.......

If the plugs are fine then it may not be as catastrophic. Just so you know why I'm telling you this, my WK1 showed an identical code BECAUSE I blew my motor. And I don't mean I went down on it!


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#15 ·
Damage on the electrode, closed gap of the electrode, dings and dents on the electrode. If it was a catastrophic misfire it will tear some piston skirting and possible chunks of cylinder walls off and the debris will be forced into the combustion chamber thus smashing into the spark plug electrodes in that particular cylinder. The chunks most likely will be spit out the exhaust valve. Although mine ended up in the intake manifold. Most likely due to the vacuum of the blower once I let off. I hope this helps and I hope you check that #3 just for safeties sake.


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#14 · (Edited)
As for the rattling if its your valves then its because you removed the center muffler/resonator the big suit case one it frees up too much flow causing the valve to rattle. Did this on mine when I removed the center one then I went back to stock because I realized after 30 minutes I couldn't stand a loud exhaust anymore.

The H-pipe didn't seem to do much for evening out the flow I would've went with an x-pipe it quite possibly would've fixed it and allowed the flow to be more even and no more rattle (possibly). Right now you have too much flow out of one pipe than the other thus causing the rattle which was what mine was doing also.

Don't just go flushing money down the drain going back to stock, figure out what to put in before the valves to even out the flow, x-pipe? Smaller resonator? Maybe putting the stock suitcase muffler in the center back in and leaving the 2 rear one straight piped.
 
#16 ·
like tugboat, and others said check the plugs. look for a much larger gap than spec. check the tip of the plug for color, black/white.

also, if the car runs normal and isn't vibrating and shaking like crazy at idle, your computers are doing a good job compensating for the misfire and it's probably NOT a dead miss.
you'll be ok driving it to get it looked at somewhere. i wouldn't be throwing out the word catastrophic just because it's an isolated cylinder misfire.
 
#17 ·
When I blew mine I regapped the plugs, threw them back in and it ran well enough that you could not even tell it had been blown. Sadly my bore scope camera showed otherwise. Power didn't even seem down after the ring land let go.


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#18 ·
in all honesty, taking it in to the dealer for a scan would prolly be in your best interest(did i really just say that???) for roughly $100 or less youve got a much better chance of finding out what is ACTUALLY happening with the misfire as oppose to just throwing parts at it. definately not saying let the dealer do the repairs if necessary but they DO have the electronics to see a lot more detail about the issue than you and your trinity do...once youve got the issue identified, then we work on how to get you back to normal as cheaply as possible.
 
#20 ·
If he has a tune and he blew his engine there goes the warranty, buh-bye. Stay away from the dealer with that thing tuned and showing misfires. Time to pull your big boy pants up and learn how to diagnose what ya broke!


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#21 ·
Tuned??? i was going off of his sig saying bone stock.....if there is a tune installed then that presents its own issues.....Blown7 can answer this question as my next statement is based off of internet reading and rumor but i was under the impression that the WK2 ECMs had the ability to store the modification history to their programming, as in even if you pull the tune back out and reinstall the factory setup the ECM stores and shows the past programming events when plugged in on the Jeep scanner.
 
#22 ·
Sorry bro, read his first post. He has a trinity on it. So like I said, dive in and see what's up.


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#23 ·
Alright guys! Update. I took the beast to my buddy and he realized my injector cord was loose. He said when he pushed it he felt a click, so I am hoping this is what it was. Apparently this was a problem on some WK1s who were getting the same error codes. As for my exhaust rattle, I said F it and decided to weld open the valves. After doing that I redid my tune and it seems fine. I have driven it and have a SLIGHT decline in MPGs but nothing too crazy. I will keep looking at it to see if I can see any changes.

If it is going to drop MPGs by a ton then I was planning on getting an "legit" exhaust anyway so I am not going to worry too much. I do have an exhuast leak in my right side so I am taking it back to get everything patched up tomorrow or the next day!

I am too happy that this was not a big deal as only two dealerships in Georgia had the parts needed for my coil/plugs. Thanks to everyone who helped out!
 
#24 ·
Phew! That must have been quite a relief. As far as welding the valves open is concerned, I'm surprised you got around the associated power drop by tuning. Good for you.
 
#25 ·
Thanks! Honestly if anything it feels like I may have gained power! Sometimes when I lay on it I get surprised! That rarely happens anymore considering the cars I have been lucky to own haha. You can't beat the sound either. It is LOUD. Now I just have to get my exhaust looked at after that ******* hit me!
 
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