Intermittent Misfire?

[34GeeTeeTee]

thanks for the replies again.

the boost controller is just the manual boost T, the cheap $30 ones.

not sure i get how the boost is working, well specifically why the minimum would be 1 bar? my standard turbo was set to 10psi. now with the hiflow the shop set it electronically to 11 (ok well on the dyno sheet that is where it is making the power). that said, my gauge can be pushed to 14.

Fuel pump is stock also.... my plan was to only upgrade things when and if the break. Hence the turbo.

Thanks again!

[75coupe]

hmmmm. changed plugs a few years ago... that could be the prob.

I woudnt be waiting for things to break before replacing them, cause the next thing could be your engine, due to leaning out.

upgrade fuel pump.

Stock ECU cant be tuned, so they just turned the boost up, probably just before it went rich&retarded.

I reckon your safest two choices are to turn boost down and read lots of SAU to learn what it is your driving or take it to a respectable mechanic to fix.

buy an aftermarket ECU, if your impressed by a highflow accompanied by all the stock parts, then you'll loose your shite when you get a tuneable ECU and fuel pump.

and yeah which is it, an electronic or manual boost controller???

Edited February 20, 2012 by 75coupe

[34GeeTeeTee]

Its a big result for a stock ECU etc.... Mine struggled to make 200rwkw with the power FC due to maxed injectors.....

[MAS_R33]

thanks for the replies.

As said this came from shop which are a very reputable mob. I don't ever touch any of the car myself and this includes upping or lowering the boost!!

They had it on the dyno and managed the boost, etc through there equipment. They agreed with me that I want it to be as reliable as possible as it is my daily driver.

This was done so that it wouldn't lean out etc.

Don't get me wrong, they seemed quite surprised with the power result of the car (as was I!!!). I wasn't too fussed about power output, just wanted to make sure it was reliable but am really happy with the power it did make!

I spoke to the guys again and they said it would definetly be a faulty coil pack. they were happy with the car with everything else and said given it is so intermittent (sometimes happens at 3500rpm, sometimes 5000rpm and sometimes it doesn't).

Rather than get them to change coilpacks and plugs (quoted at nearly $900!!!) I thought I'd see if I could do some of this myself as funds at the moment are running low!

If it gets any more difficult than plugs or coilpacks then it will go back to the shop!!

thanks

Edited February 21, 2012 by MAS_R33

[Sparky206]

Your just hitting Rich and Retard. Search the forums for it. Trying to run anything other than stock on a r33 is just a waste of time, the ECU's absolutely hate it when they see anything their not expecting.

Whats happening is your hitting the limit of how much air the ECU wants to see going through the engine. When it sees this, it pulls all timing until its corrected. Thats why it'll feel like you hit a flat spot in the rev range.

If your running 11psi you could try dropping it to 9 or 10 if your JUST hitting it occasionally, but either just run it stock or get a nistune and avoid all these hassles

[MAS_R33]

ahh ok.. so this would be the case even though it is intermittent?

ie. sometimes i can drive it and nothing happens - even hitting high boost

sometimes it will happen at 3500 (before hitting high boost)

and sometimes it hasppens at high boost.

I would have thought if it was ECU it would be at a consistent spot?

cheers

[Sparky206]

Yes because the airflow through the AFM isnt going to be consistant. If your right on the edge, which you are running 11psi, sometimes you'll trigger it and sometimes you wont

[GTSBoy]

Depends on the weather too. Cold dense air will trigger it. Harder to do it on hot days (if you're on the edge).