Help! Im Stumped

[r32woohoo]

Hey guys/gals

My car has started missing at idle out of nowhere and i cant quite figure out why

I know most lines have a very slight miss when idling and mine did too

But now its constant like every 2 seconds, not quite as bad as having dropped a cylinder though.

-It misses more as the oil temps go up

-If i step on the gas in neutral and hold the revs eg: 2000rpm it still misses a bit but not as bad as when its idling

-It used to misfire a bit on boost (16psi) with the old coils but with the new ones it doesn't at all.

-I'm not down on power at all and the car drives normally.

Ive just put in a set of new justjap coilpacks, new spark plugs and gave the afm and aac valve a good clean

The coils helped a bit but it still misses

Raised the idle a tad and that didn't help

Ran some injector cleaner but i might try another brand as well

Checked all the cooler piping for leaks and my vaccum pressure hasn't changed

Fuel filter has been changed

I'm going to try a different ignitor pack and see if that makes a difference

I've considered a bad injector, how can i tell if one of my injectors are blocked/leaking?

What would i be looking for if i put it on a dyno?

Would the TPS have anything to do with this?

Im running an RB20 with:

RB25 highflow

GTR injectors

Z32 afm

040 fuel pump

Ecu remap

What else could it be?

Edited September 28, 2007 by r32woohoo

[moonus]

cas?

[r32woohoo]

I considered the cas too but wouldnt that cause other problems as well?

[r32woohoo]

Anyone?

[Haysey]

sell it and buy an S4

thats my answer lol

[sav man]

Mine has a slight miss at idle. I got hold of a widband 02, turns out i'm running between 19:1 - 20:1 AFR at idle. And only way to get it to idle at ~1000rpm is to have that AFR. When the car is cold it starts off around 14:1. I'm dropping my engine out next week and i'll clean the aac valve while it's out.

[SECURITY]

im thinking igniter pack or CAS.

does anyone know if the igniter packs and CAS are interchangeable between the rb20 and rb25 (s1)?

Edited September 28, 2007 by SECURITY

[fob2nv]

CAS.

Edited September 28, 2007 by fob2nv

[r32woohoo]

Seems like everyones leaning towards the same thing.

But why?

Anyone have a spare cas to lend me?

Edited September 28, 2007 by r32woohoo

[paulr33]

im going to go with coilpack related either loose plug or something simple / obvious

if the TPS is toast the ecu goes into retard mode and revs to 1500rpm and stays there

[zebra]

I had this problem, For me it was plug gaps were too small once brought back out to.8mm problem solved.

Hope its a simple fix like that for you

[r32woohoo]

Ok so i can rule out the TPS.

As for coilpacks theyre all brand new and the plugs are in nice and tight.

In my head if the coil plugs were loose or the loom was shot then wouldn't it be intermittently missing everywhere, and dropping a cylinder? I don't think its dropping a cylinder coz it doesnt sound that bad, and theres no smoke spewing out from the extra fuel

My miss is constant and only at idle

my plugs are at a .65mm gap at the moment.

thats what i was running with the old coils for about 6 months before this started happening

now that ive got the new coils i havent been bothered to open the gap up but i'll give it a go tomorrow

Edited September 28, 2007 by r32woohoo

[zebra]

My plugs were down about .6 aswell as i was chasing a miss-fire (which turned out to be a loose wire on a coil.

Once i fixed the coil it would miss on light load / idle re-gapped the plugs to .8 and haven't had a miss since.

So I suggest you try re gapping your plugs first (even if i is a pain in the ass)

Andrew

[T04GTR]

give it a comp test.

[r32woohoo]

Well i've opened up the gap to 0.8mm

Still no good:(

But at least it doesn't miss on boost like it used to

[hectic32]

yeah got the same problem here and my throttle position sensor is highlighted on my power fc could this be a cause really need to know thanks

[sunnycoast]

Having the same problem here guys. Dropping Cylinder 2 when the car warms up.

So far, new items installed:

Spark Plugs

Ignitor

Coil Packs

Coil Pack Loom

Tried that and Cylinder 2 still drops out when the car is warm. Also, Cylinder 2 comes back on when driving or revving the engine (but with a misfire).

Any other ideas? CAS?

Appears to be a temp issue..anyone?

[sunnycoast]

Anyone?

[Haines]

does yours pop on decel alot

if so it could be your injector scaling / lag times

[sunnycoast]

Doesnt pop as such...running very rich though... goes through quarter of a tank in 25k's of street driving.