Car Sounds Like A Wrx ... How Do I Stop This?

[PSIKO]

Hey guys,

Earlier tonight my car (which had been driving absolutely perfectly) all of a sudden started running like absolute crap, and what I can best describe as sounding like a WRX.

I limped the car home (50kms, sigh), and it seemed to only do it once the car had come up to temperature from that point on.

I am not sure whether it is the fuel filter, I haven't really changed it since I swapped to e85, though in saying that I haven't had much of a chance to drive it much

Modifications which would have an impact are:

• RB26DETT
• ViPec ECU running MAP
• Running on e85
• New spark plugs within the last couple of weeks
• -5 turbos, full aftermarket exhaust
• Splitfire coils (probably less than 1,000km's on them)
• Metal headgasket with ARP headstuds freshly put in within last week or so

I've only just had it put together, and was dyno'd last week and was fine there

A mate noticed when I pulled out of the car park he thought he saw a puff of smoke but couldn't see what colour it was but thought it might be white (with nothing else after that initial small puff), perhaps ethanol perhaps something else?

A niggly problem that I have with the car is the electrics - there's a circuit breaker (180 amps or something large) which seems to sometimes prevent me from starting the car up (this happened tonight too) - could this have an impact, as there's not enough voltage going to coils or anything like that?

If anyone could suggest anything, that would be greatly appreciated.

Of course I'll be contacting the tuner, but just to get some initial ideas in case it's something easy like a fuel filter (which I will also be replacing)

Cheers!

[iruvyouskyrine]

Running on 5 cylinders. Did you wash the car recently? Most common issue is water sitting in around the coilpacks, or your coilpacks could be on the way out.

Leave the car running rough and disconnect each coil pack one at a time until you hear no difference in sound. That's the dud one.

[Badgaz]

intercooler piping leak tested? burst hose?

[Sinista32]

Agree with running on 5 Cylinders

Could be anything that's associated with stopping that cylinder from firing or firing at the correct time

process of elimination starting with the method above

[PSIKO]

Cheers for the replies guys,

Yep car has been washed recently - however is it odd that it would suddenly start doing it, and across the full rev range, if it was from water from a recent wash?

Will test the cylinders this weekend as you both suggested

Badgaz - doubt it's intercooler as it's not running MAFs, cheers though

Thanks fellas

[GTSBoy]

Ignitor module also a common suspect when it starts once warmed up.

[Blackkers]

I dropped an injector once and it ran on 5 cylinders. Sounded like a wrx too, rough when driving and idling. But on deceleration the engine felt smooth again. So in gear above ~2k rpm with 0% throttle the engine felt smooth. That's how I knew it wasn't an internal engine issue

Maybe give that a go if you're worried. I suspect coilpacks or plugs

[iruvyouskyrine]

You wouldn't believe how many times I have seen this after people was their car. But yeah pulling the clips off the coilpacks and injectors progressively is an easy and almost guaranteed way of fault finding the problem.

Good luck

[Badgaz]

Cheers for the replies guys,

Badgaz - doubt it's intercooler as it's not running MAFs, cheers though

Thanks fellas

So your map sensor, iat sensor and tps are reading correct? Can you data log on your ecu?

[JordansR32]

A similar thing happened to me before, one of the injector clips had come loose and looked like it was on the injectors but was just off and wasn't making contact.

[PSIKO]

Thanks guys for all the input; turned out to be the ignition module

Cheers fellas!

[GTSBoy]

Super Supreme or meatlovers, thanks.