Missfire Boost@4500-5500 RPM - The Answer! (for me at least!)

[johnbarry88]

ill have to try this because I too have the same problem

[R31HOOCH]

Hey all... I'm havin some problems with my RB20DET thats in an R31... Its a silvertop RB20 from an R32 and its running the standard R32 ECU with basic mods such as FMIC, 3" exhaust and pod filter... I went through a huge puddle a few weeks back and ever since its just been problems... That day after going through the puddle, it started stalling when the revs were coming down as i was clutching in and braking to stop... The first few times it started staight back up but after a while it started being a real bitch and took a good cranckin as if it were flooded or out of petrol or somethin... The thought came to me that some of my coil packs or the ignition module got wet or somethin so i went and fuelled up the drove it around for a while... After about half an hour it seemed to be all sweet again so i drove around for the rest of the day...

When i went to start it up the next day, it just fired up then died straight away... I pursisted with this until finally with a little bit of pedal pursuasion it spluttered to a steady idle... When i went to drive, it was fine whilst taking off and going slow with boost pressure still in vaccuum but as soon as i start to put my foot into and it starts coming onto boost i just lose all power and it starts broad minded persontering and fuelling up then usually lets of a big backfire with a nice flame... It is the same in all gears in all conditions... Recently i have replaced 2 coil packs, had the alternator overhauled, cleaned the AFM, checked all intercooler piping, replaced the O2 sensor and checked the fuel pressure, pump and regulator...

Has any1 had similar problems or have any ideas on what the problem might be??? Its really starting to do my head in!!!

Cheers every1...

[GTR_Legend]

Mine started missing 2 days ago between 4-5k.

Will check the coils 2night!!!

[julion]

I have a non turbo r32 RB25de

it misses around 4500-5500. how do i take out the coilpacks to tape em?

sorry to be noob.

[GTR_Legend]

take off the intake pipe going across the engine to the throttle body, take off the cover between the cam covers, then rip em out

Fark!

mine were fine but couldnt get the spark plugs out to check them, they are only 1 month old too!

every size socket except the one i needed, will check them on the weekend.

BTW, mine only started after i cleaned the aac!

[GTR_Legend]

take off the intake pipe going across the engine to the throttle body, take off the cover between the cam covers, then rip em out

Fark!

mine were fine but couldnt get the spark plugs out to check them, they are only 1 month old too!

every size socket except the one i needed, will check them on the weekend.

BTW, mine only started after i cleaned the aac!

Damn spark plugs, issue fixed.

even though they were 1 month old iridiums! lower gap now too!

[khunjeng]

once I replaced my coil packs with spitfires my problems when away...I also replaced with soem NGK XIs later on...works awsome now.

[GTR_Legend]

once I replaced my coil packs with spitfires my problems when away...I also replaced with soem NGK XIs later on...works awsome now.

hope it does for me. Tracking the package from japan shows that they arrived @ aus post from customs yesturday, so should be here today, whoo hoo!!!!

[Kennedy]

I just replaced my lecky tape with industrial grade silicon. Works perfect. Pretty good for $11.00.

Feel sorry for all the guys out there who have bought splitfires when all the time it was just probabaly just a crack in the coil.

[GTR_Legend]

results are in.

I checked my coils twice and even had a mech check them, nothing visable!

Just due to general wear i guess

Put in my split fires last night, all good now and car feels smoother!

Sweet. up the boost goes again

[Kennedy]

Let me also say that I could not spot any cracks either. But apparently I had them. There was no scoring or lines anywhere but it was guarenteed to miss at 4500RPM.

I would suggest that all people at least try this mod before buying splitfires.

[GTR_Legend]

yes, all comes down to what you want to do, even if the fix did work for me, i would still buy the splitfires

but thats just me!

[Rolls]

Let me also say that I could not spot any cracks either. But apparently I had them. There was no scoring or lines anywhere but it was guarenteed to miss at 4500RPM.

I would suggest that all people at least try this mod before buying splitfires.

The dark shed is a good way to tell, warm the car up and run it in a dark shed with the valley cover off, spray some water mist over the top, if they are cracked you should see small blue arcing. Go easy on the water though.

[Rolls]

Well I finally got some splitfires, at the same time I replaced the plugs with new ones with a 1.1 gap (old ones were down to .6. Took it for a spin then and it poped once at 5500rpm out of about 6 high rpm 2nd gear runs.

Pretty happy with the result, it used to pop like crazy and loose lots of power once I hit 5k.

Ill see how it goes this week and if I keep getting a few even minor pops at those revs Ill gap the plugs down to .8 and it should be perfect.

Edited September 29, 2006 by Rolls

[JAS-25T]

Im finally in the club.................

going to change plugs and check the coils while im at it.

[JAS-25T]

Sorted just with new plugs.

inspected all coil packs. no signs of cracks

[JAS-25T]

4 days later with the new plugs. the problem returns.

Has anyone got some decent pics of what they taped?

Might have to try this before i fork out 600 for splitfire coils.

[Link]

4 days later with the new plugs. the problem returns.

Has anyone got some decent pics of what they taped?

Might have to try this before i fork out 600 for splitfire coils.

Jase, before u shell out for coils let me try something on mine first and ill let u know if it works....going to try the silicon & tape trick

Might just save us some $$

[JAS-25T]

Ill be in contact!

[Kennedy]

Jase, before u shell out for coils let me try something on mine first and ill let u know if it works....going to try the silicon & tape trick

Might just save us some $$

Try tape first as it will only take 30 minutes or so. Tape works fine...but it doesnt last longer than a couple of months. If the tape works then silicon is the way to go.

I had no visible cracks on mine either but silicon fixed it.....after I narrowed it down to the coils with tape.

Good Luck