Hi I have a 2006 MR and it has a Turbo XS Turboback exhaust with a Works HFC and dynotuned by Shiv...basically the V400 package with boost emulator. Anyways it has been on there for about 15k miles and works great but lately I have had a miss at idle and it idles a little rough, better with the AC on though. But just last week I have been throwing the P0304 code which is Cyl 4 misfire. That would explain the miss at idle but it has me concerned. I went and put 4 brand new OEM laser iridium plugs in it and even ran some Seafoam threw my gas tank but it did not help much. Also when I pulled my plugs they are a reddish tan color, is that normal? So is it the tune causing this or is possibly a injector going out or a coil pack. The only thing that leads me to believe injector is there is dirt where the #4 injector is so could it be leaking or going bad? I am sceptical about taking it to a dealer and having them screw something else up or flashing my ecu back to stock. I also bought a Tactrix cable but I am not sure at what to look at on my logs that would indicate anything important. Any advise or if anybody else has experienced this problem help me.

 

coil packs
spark plug
or a motor thats gonna go!

 

Try different spark plug wires.
Possible boost leak.

 

Well I dont think the motor is gonna go...atleast I hope not, it still runs great and has lots of power. I am going to try and switch coils and wires with a friends Evo 8 to rule them out or not...they are the same as a IX right? I am leaning towards the tune or bad/leaking #4 injector...it seems really loose connecting to the fuel rail, I can twist it around pretty easily and it looks dirty in that spot like it has leaked some. As far as boost leak I dont think it does, I have checked all the hoses and they are tight and it is singling out Cyl. #4 which a boost leak I dont think would do that. I also want to know from other IX owners what there plugs look like...mine are reddish tan color on the tips. If anybody else has experience with this or the injectors give me advice!

 

you're an idiot

 

don't twist the injectors. or you going to shred the o-ring and the next thing you know a piece of it get in the injectors and kaboooommmmmmmmmmmmm

 

The wires are different on a 8.
Its most likely a boost leak, same symptoms that my buddy had.

 

Just the wires are different or are the coils different too? Also if I had a bad enough boost leak why would it only cause the P0304 Cyl.4 misfire. I am still making full boost and it spools like normal and all hose seem tight unless its somewhere I cannot see.

 

Do a boost leak test. Then a compression test. Inspect the condition of the plugs.

 

Well the plugs are new OEM ones. The electrode looks reddish/tan...is that normal. I am also going to do a boost leak and compression test this week too.

 

Bump for any answer....I have PM'd and called Vishnu with no response (Shiv was out of the office) Some other tuners I have talked to attribute it possibly too aggressive of timing. I ruled out almost any ignition part I believe so its down to #4 injector or the tune. Anybody else have problems with a Vishnu tune having too much timing?

 

Misfire on only one cylinder usually is:
Sparkplug
Coil pack/ plug wire
injector on that cyl.
low compression on that cyl.

....and I don't think it's a boost leak.

 

do a compresion test...redish tan dont sound bad...

 

Like I said I am 99% it isnt the coils...possibly the plug wires but I highly doubt it. #4 injector looks like it may be a tad leaky...maybe a couple drops, is there anyway to diagnose a bad injector or oring without taking it out? Also I really dont see how the compression would be low, it has lower miles and hasnt been driven that hard. But I will most likely check to confirm. Any other ideas?

 

ok this one fixed it for me. TRY A DIFFERENT GAS STATION.

sometimes if you get bad gas it will throw the code. took me about 4 tanks of gas to find a gas station here in town mobile 1. i've told everyone about it. some guys have claimed 60mpg more per tank of gas.

i bet you its your gas.