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Unfixable Miss

SimonR32

By SimonR32,
in Engines & Forced Induction

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Kaido_RR Grand Master

Kaido_RR

Posted
Posted
ok to answer some questions...

i the rings/pistons and valves are assumed to be fine as there is virtually 0 blowbye from the engine plus the fact that the miss goes away if the plugs are gapped low enough...

hey Cerbera,

i don't know if this will help but ur problem looks similar to mine.

I had stock coils and spark plugs gap at 0.4mm, i then change the plugs and had them gap to 1.0mm, 0.8mm and 0.6mm and i would get miss at all 3 gaps. put old plugs back in at 0.4mm and it stop the missing.

i ended up getting splitfire coilpacks a week ago put them in with new plugs with 0.8mm gap and everything was ok..

Also my idle was abit over the place and once replacing the coils it has gone away.

dont know if this helps but i through i say

cheers michael :D

Lazy-Bastard Grand Master

Lazy-Bastard

Posted
Posted

I feel your pain.

I just did a bosch coil pack conversion and am getting really bad misses at relatively low boost ~10psi

Originally I had my plugs gapped at .7 (they were about 10,000k's old) and at 10psi it would miss on what sounded like all cylinders.

I got some new plugs (same heat range 6) and left them at the 1.1 gap and the problem is exactly the same.

I am going to try gapping the plugs down to .6 tomorrow and see if that helps.

Keep us posted on your progress Cerbera

  • 2 weeks later...
SimonR32 Grand Master

SimonR32

Posted
  • Author
Posted

remapped computer went in for the weekend as someone borrowed my power fc

everything is fine, pulls very smooth right through till redline with no miss

im assuming therefore that it is a set up problem with the power fc... either the charge and dwell times or something else?!?

could the japs have done anything funky with my wiring loom to make the remap work and cause the power fc to play up. car was originally a auto

RedDrifter Experienced

RedDrifter

Posted
Posted

Mate It could be from over advanced ignition somewhere in the power fc map.

I have seen this before with a mates RB20.

Ignition was so over advanced it wasn't detonatiing but rather not ignighting at all.

Just another thing for thought.

Good luck.

pnblight Mentor

pnblight

Posted
Posted
remapped computer went in for the weekend as someone borrowed my power fc

everything is fine, pulls very smooth right through till redline with no miss

im assuming therefore that it is a set up problem with the power fc... either the charge and dwell times or something else?!?

could the japs have done anything funky with my wiring loom to make the remap work and cause the power fc to play up. car was originally a auto

to me this sounds like a miss set parameter etc (ie like boost control unit enabled with no unit installed etc)

i would when pfc re-installed do a complete check of all settings to ensure correct program setup

( i would place a very good bet it's a very simple problem you just need to find it)

try and get hold of a similar setup pfc tune and use as a cross reference

SimonR32 Grand Master

SimonR32

Posted
  • Author
Posted
to me this sounds like a miss set parameter etc (ie like boost control unit enabled with no unit installed etc)

i would when pfc re-installed do a complete check of all settings to ensure correct program setup

( i would place a very good bet it's a very simple problem you just need to find it)

try and get hold of a similar setup pfc tune and use as a cross reference

i know exactly what u mean... the power fc was second hand when i got it but appeared to have not been installed, but then again u never know. its not the boost control unit, cause otherwise the car wouldnt run at all :)

i'm going to see the tuner soon, so if the charge and dwell times dont work i think we will just reset the ecu and start from scratch and see what happens from there

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