I just recently installed headers on my car, which involved new plugs, new wires, air pump removal, and EGR removal. For some reason I'm now having ignition problems Before the header install the car was running perfectly.

1) Occasionally at idle I hear a popping sound out the exhaust like one cylinder isn't firing properly

2) The car will missfire under 2500 rpm if I go passed half throttle, but once it reaches passed 2500rpm the engine kicks in and runs perfect. Then the missfire comes back at 4000rpms and lasts till about 5200rpm then the engines kicks in again and pulls strong to 6100rpm.

I put the car on the scope and the #5 cylinder was acting up. I pulled the plug and it was wet. So I replaced the plug and the wire. The car ran better, but still displays the problems mentioned. I even took apart the opti and cleaned it but no change. I'm loosing my mind over this

Is this a sign of a bad opti, or could this be a fuel problem, like a bad injector?????

Any input would be greatly appreciated.
Thanx in advance!!!!

 

Try pulling one wire at a time to see if any wires don't have any effect when you pull it when the engine is running. If you encounter one wire that when disconnected does not change the idle, that cylinder has a problem.

Try swapping plug and wire from a good cylinder. See if the problem moves with the wire and plug. If it does problem solved. If not get an inline spark tester and see what it shows for that cylinder versus a good cylinder.

If the spark still looks bad it's the opti. But if that looks good try swapping injectors from a good cylinder and see what that does.

Good luck to you

 

MAKE SURE!!!! you dont have the wires mixed up on the opti!

left side from top to bottom its
4
6
8
2

right side from top to bottom its
5
3
7
1

 

All the wires are connected properly. I isolated that I have a problem with #5 cylinder, so I guess all thats left is to check the injector. If that doesn' t work, it must be the opti. Is it common that when an opti goes bad that it only affects one cylinder????

 

Come on guys there has to be someone thats gone through this!!!

 

wish I could help man I'm in the same damn boat today, for two days now mine is running like crap. I have longtubes, new wires, new plugs and it started running like this 2 days ago now. I'm at the point of just installing an OPTI on this 75k mile car and having the confidence that is not the problem afterwards. If you get it fixed could you PM me? I'm working on mine after work tomorrow depending on what feedback I get here, if the consensus is bad OPTI I'm replacing that SOB ...I'll let you know if it fixes my problems. Mine sounds like it's running on 7 cylinders or something and pops from the unburnt fuel while at redlights idling...it sucks..sounds like a HooptyTech car

 

Yeah thats what mine does. Pops from the unburnt fuel.
Keep me posted
I'll PM you if I figure it out

 

you have a busted plug or burnt wire. just look under you hood when its dark out for any flashing of light and/or archs off the plug boots. i am about 100% sure this is your problem even if you swear they are ok... only way to know for sure is to look for the light show. i burnt a plug the very first day i put on my headers b/c i tried to use those stock aluminum covers on my taylor wires and they ended up melting a small hole in the side of 2 of them. #7 and #5. good luck i hope you find the bad plug/wire!

 

Dude the man knows what he's talking about Why don't you do like he suggested and stop guessing.

If you don't want to get an inline spark tester for $10.00 then pay a shop $40.00 to put in on a scope. this will tell if the spark going to the plug is bad It will have taken you longer and drained your wallet more

We can tell you how to do it but we can't make you do it.

 

As mentioned before I did put my car on the scope and #5 had bad spark. Then I changed the plug and wire again and still the same problem. I just wanted to get some feedback before I went purchasing an opti. I'm going to try changing the #5 injector first and see what happens

 

Just curious but why check the injector? You said that you had a wet spark plug (fuel on it) you are getting popping in the header (burning raw fuel from header heat) and that the scope showed bad spark on #5. Sounds to me like the fuel is getting there and ignition of the A/F is the problem. Seems the problem should be isolated already to plug, wire, or opti.

Curious more than anything as to what part of your logic is missing from mine.

Good luck getting her running properly again.

 

Ok.
I just got back from putting my car on scope again. And this time it shows that all the wires are fine but the #2 and #5 spark plugs are fouled up with fuel????
I'm going to change the 2 plugs and see what happens. If they get fouled up again I guess that means I have leaky injectors

 

or it could get a weak spark there . If you wanna check leaky injectors, pull the rail, make sure the clips are in and prime up the lines. if you see fuel leaking, its a leaky injector