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Habibi240
10-06-2015, 04:50 PM
Searching and reading for a while !
Figured I'd make a thread

So my s13 sr has a random misfire at idle

Has a really bad cut out putting anything after 20% throttle

I don't know if my worn cam lobes have anything to do with it
<a href='http://i.imgur.com/HRp65Rh' title=''><img src='http://i.imgur.com/HRp65Rh.jpg' alt='' title='Hosted by imgur.com' /></a>

Timing marks are correct but when using a timing gun it was way off to get it at 15* the cas is at the end of the adjustment window ...

Things I've tested

Tried a freinds igniter
Unplugged each coil pack and injector
Tested cts and cleaned connection
Cleaned maf
Checked all clamps for possible boost leak (haven't done a test)

Mods
Walbro 400 (I know it's excessive)
Stock fuel lines
Z32 fuel filter (1hour of run time on it)
Stock 370inj
Wiseco 9.0 comp Pistons 87mm
Apexi 1.5 - 87
Stock valve tran fresh seals
T28 s15 bb
Fmic

It was doing the idle bog/misfire before I had a piston meltdown but only popped every now n then under load .

I'm gonna do a boost leak soon but in the mean time can I get some ideas tossed up..

Let me know if you need any more info.

Thanks

Also I don't know afr #s yet . Wideband on the way

cbeuglas
10-06-2015, 05:11 PM
Here are a few ideas. Clogged fuel injectors. Test fuel pressure. TPS has to be unplugged when checking timing, also I could not get an accurate reading off the timing loop. I had to use a plug wire (ka24) between the number one coil and number one spark plug to get an accurate timing reading.

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cbeuglas
10-06-2015, 05:13 PM
Also what is the vac. at idle as it could be very well be a boost leak.

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Habibi240
10-06-2015, 05:26 PM
I have a cheap ass boost gauge that only reads boost and I did the spark plug wire loop trick

Habibi240
10-06-2015, 05:35 PM
Oh and plugs gapped at 32

blksylv
10-06-2015, 06:02 PM
Have you tried another CAS?

Habibi240
10-06-2015, 06:29 PM
No actually I haven't I could test mine right ? Imma search that now

blksylv
10-06-2015, 07:25 PM
I'm not too sure. I had an issue with an misfire at idle, replaced a bunch of things and it ended up being the cas. My misfire would get worse the longer I drove it. It would bog a little under boost though.

Sills
10-12-2015, 03:10 PM
My Rb had a nasty misfiring issue, especially in the higher rpm range.
I tossed in some fresh Ngk V-power BRK7E(s?) plugs and gapped them to 0.22.
Running perfectly now, way better than the old NGK iridiums that were in it.
Only costed me about 25$ for 6 plugs. Not sure what ones to use in an Sr as mine blew up long before I got to change the plugs in it.

Habibi240
10-12-2015, 03:53 PM
It was my ignitor chip I forgot to update you guys