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R34 Coil Packs - What Are The Test Values? Help!

Zensoku

By Zensoku,
in General Maintenance

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Zensoku Collaborator

Zensoku

Posted
Posted

My RB25 has started dropping down onto 5 cylinders very randomly, which I initially thought was a misfire with the spark plugs. Used to happen under load 3500-5000rpm which prompted me to change the plugs...

Plugs didn't help, and now it seems more regular now and drives like a "lumpy V8" most of the time now instead of the few seconds it used to drop a cylinder....

During the painstaking process of changing the plugs, I quickly put the multimeter onto each coil and got:

Cylinder 1: 852 Ω

Cylinder 2: 903 Ω

Cylinder 3: 687 Ω

Cylinder 4: 809 Ω

Cylinder 5: 859 Ω

Cylinder 6: 851 Ω

Now, these figures seem very high compared to the series 1 RB25's, (0.7Ω is the norm?) but I believe my coil packs have the igniter built into them. (unlike the early RB25's which have the igniter inline before the coils)

I have a Japanese Engine manual, but couldn't find anywhere how to properly test these coils and what the normal values are.... Can anyone help? Cylinder 3 looks like the culprit....

Oh, and the ECU self-diagnosis mode shows up error number 21: Ignition Circuit - "No consecutive ignition signal while the engine is running"

  • 4 weeks later...
Kirill Rookie

Kirill

Posted
Posted (edited)

I got the same "Error 21" yesterday. the engine sounds as usual and but for the "Check engine" light I wouldn't have noticed any difference.

I'm going to run power balance check one of these days - hope it will help to find out whether the prob is in one of coils and in which one.

BTW, how to get to the coils and spark plugs on R34? I'm affraid that I won't fix the problem without getting to them, but I absolutely have no clue on how to remove part of intake manifold (and what exact part shall I remove to get there).

Edited by Kirill
Luke 34GTT Explorer

Luke 34GTT

Posted
Posted (edited)

I have exactly the same problem and its driving me crazy! The engine check light comes on and it starts missing on one cylinder etc, and its is always a code 21 when i check it. The annoying part is that it is so random and it doesnt "stay" missing long enough for me to be able to check out what coil pack is playing up etc. Sometimes it will go for 3 weeks with out missing a beat, then other time it will do it 2 or 3 times in one day. Do you guys know, if there is anything else other than the coil packs, that will cause the engine check light to come on (code 21)?

Edited by Luke 34GTT
  • 2 weeks later...
Abo Bob Grand Master

Abo Bob

Posted
Posted

Look I've got no idea about the values you posted above but I can tell you that my coil packs died at a genuine 66,000 k's and having been around here for a few years now I can tell you that the R34 coil packs are quite likely to die between about 50,000 and 100,000 k's.

All you guys have the same issue.

Also I would not recommend getting second hand ones even though they may work fine now because eventually...

Splitfires are the way to go I'm sorry to say.

  • 1 year later...
PLYNX Mentor

PLYNX

Posted
Posted

Tried to find the same basic issue with my car and wasnt sure if it was the coil packs and didnt want to lay out 500 odd bucks unnessesarily. So I pulled then out cleaned then and coated them with polyester resin. It turned out to be the problem even if I couldnt see the cracks. Fixed It a treat

  • 1 month later...

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