Misfiring Rotrex K20a HELP!

[Tom eg5]

My coolant temp sensor seems to reading correctly as its almost the same as my defi gauge. Yeah, when i pull the plugs out after a run they are a little powdered whiteish, but not too bad. No not just yet, but ill try and borrow my mates known working ones and see if it fixes the issue.

[Tom eg5]

Checked known coilpacks and a different KPRO.. No deal.

[Tom eg5]

Also, my cam angle is going to 50* at 3500 (Basically when it misfires and hesistates and rev's barely climb) and then easing off to 30* at the higher rpm's?

It seems to be happening as soon as i hit the low vtec boundary

[raidbaws]

White plugs mean that it is running lean... But you say that you running 11:1 AFR

[Sexc86]

One of the results running E85 is that it strips / cleans your fuel system, this is usually good but can be a problem on your first initial use because of how it strips your fuel tank and can block injectors downstream (you will probably still show fuel pressure but get little flow to your cylinders). Take out your injectors and get them cleaned. Could also be a good idea to replace all your filters (especially if you have changed to non OEM units) and run a fuel / injector cleaner through a tank of fuel too. I don't think a fuel based miss-fire would be enough to show a majorly leaner wide-band reading either.

Honest bet this will fix your problem, however few other things to try

* leakdown test maybe you valves are passing compression through the seat ?
* try stick to copper plugs heat 7ish - always had miss-fire problems in the past with boosted setups and iridiums.
* Im not too familiar with the Kpro - but can you bring up in your datalog the firing signal for each individual coil pack ? possibly determine if this miss-fire is only happening in one specific cylinder or if its random over them all?

Good luck

[raidbaws]

I forgot you running e85 oops.

^ good thinking buddy. You should be able to do a 'power balance' test on aftermarket ECU's to determine if a miss is evident and using you can datalog it for various driving conditions.

[Vvvtec]

One of the results running E85 is that it strips / cleans your fuel system, this is usually good but can be a problem on your first initial use because of how it strips your fuel tank and can block injectors downstream (you will probably still show fuel pressure but get little flow to your cylinders). Take out your injectors and get them cleaned. Could also be a good idea to replace all your filters (especially if you have changed to non OEM units) and run a fuel / injector cleaner through a tank of fuel too. I don't think a fuel based miss-fire would be enough to show a majorly leaner wide-band reading either.

Honest bet this will fix your problem, however few other things to try

* leakdown test maybe you valves are passing compression through the seat ?
* try stick to copper plugs heat 7ish - always had miss-fire problems in the past with boosted setups and iridiums.
* Im not too familiar with the Kpro - but can you bring up in your datalog the firing signal for each individual coil pack ? possibly determine if this miss-fire is only happening in one specific cylinder or if its random over them all?

Good luck

Good post

[89lude]

what fuel filter are you running ash?

[Tom eg5]

Aeroflow inline. I tried bypassing it and it didnt change anything either..

Thanks for the comments and thoughts. Ill keep it all in mind.

Its not a small misfire, basically across all cylinders.. Sputtering/cutting out and barely revving any higher than 4-5k.

Could be a mechanical problem.. haven't quite got that far yet as it drives fine when not in vtec/cruising. No sensors seem to be playing up in kpro and ive checked most my sensor plugs back to the ecu and they seem fine.

Starting to exhaust my mechanical knowledge and thinking it may be something a bit more complicated... Hopefully a local tuner up here is going to have a look at it and find the problem for me!

[raidbaws]

I had a car come in with a rough idle and found that #1 piston had not enough oil to it and chewed out some of the bore.

You checked air leaks, you checked fuel pressure and leaks, you checked spark and leads.

You need to take a big step now as all small steps are exhausted ... * starts chanting * take apart the block.

P.S. Did you get fuel pressure in the rail and injectors?

[Sexc86]

^ I doesn't seem all small steps are taken yet. Before the op starts majorly ripping apart his setup he should get his injectors ultrasoniclly cleaned + flush his fuel system with a fuel system cleaner. Not sure if any fuel system cleaner would react with e85 - if in doubt run some 98.

Also just because he is getting fuel pressure at the rail does not mean his cylinders are getting the required fuel units if the injectors are blocked

To the Op - does your car have this problem if you disable vtec in your kpro ?

[Tom eg5]

I had a car come in with a rough idle and found that #1 piston had not enough oil to it and chewed out some of the bore.

You checked air leaks, you checked fuel pressure and leaks, you checked spark and leads.

You need to take a big step now as all small steps are exhausted ... * starts chanting * take apart the block.

P.S. Did you get fuel pressure in the rail and injectors?

Yep no air leaks whatsoever, builds boost good. Fuel pressure is good. Spark plugs have been changed 4 times using different heat ranges and gapping. have tested coilpacks with known good ones.

haha do not want to take apart the motor. Not going to be happy if my motor is damaged after 2 drives on the street...

To be honest if my car is cutting out/misfiring barely allowing the car to rev over 5k, wouldnt i see a huge lean spike on my datalogs? They stay at 11.2 to 11.5 the whole pull. Fuel starvation would cause a splutter but not what im experiencing i don't think.. But i can only check. Thanks for the input. Ive checked all my fuel components for blockages just incase, and my ID1000s are about 100k's old so they are brand new.

I should post up an incar gopro vid when i next take it for a test. To me it feels like an electrical/sensor problem but i could be completely wrong.

I shall keep researching and trying things in the mean time. Thanks for the help guys