Sr20 missing when on boost need help

[TripleJ]

I can't seem to figure out why but my car is missing between 3000 and 4000 rpm but only when it's on boost?

Specs a d things I've tried

Car is completely stock black top still with stock smic. Has no bov. I have changed oil filter and fuel filter new spark plugs new fuel pump new oil cleaned coil packs and cleaned maf and have reset stock ecu

I don't know why it's doing it and I don't know what else I can try?

If you need anymore info just ask and let you know

[TripleJ]

And also to add to it. It's 91 s13 that was sr20de that the owner before me did a turbo conversion to

[Jez]

Spark plug gaps.

I set my plugs to .70 with stock boost, works for me.

[Sileighty_85]

gap plugs to .028-.032

[lg54]

+1 on spark plugs

[Jez]

Spark plug gaps.

I set my plugs to .70 with stock boost, works for me.

Thats metric!!

[TripleJ]

Sweet il pull em out and check em. I did just buy a brand new set on the weekend and put them that we're made for the sr20det though that are rated 7 heat or something? Il still pull em out and check em though coz there's no lose from it

[TripleJ]

Plugs are at .7mm but I put them in on Wednesday and pulled them out now and they are really really black?

[Kingtal0n]

Its an SR20DE. how is it tuned? The answer to your problem most likely lies within the air/fuel ratio, and the ignition timing- Since I am assuming you do not have a standalone computer, probably just some sort of piggy back. Which would account for the improper air/fuel and ignition settings, which would lead to black plugs and missing/backfiring.

you should check for boost leaks and get a wideband on it, and ensure the ignition timing is adequate if possible, basically you would want to dial it back at the CAS/Distributor.

[TripleJ]

Man when I got this car it had a massive boost leak. Once I fixed the leak this problem started?

[4x4le]

Someone probably tuned it WITH a boost leak, then you fixed the leak and the mapping is totally wrong then

[TripleJ]

So I will need to get it retuned then ah lol

[4x4le]

Ah, still do some diagnostics on it first. You may have a legit problem and it would be a mistake to tune around it. Similar to what i speculated was done earlier

[TripleJ]

Yeah true. Well anyone else have any other ideas? I'm stuffed on what else to try

[4x4le]

Being able to monitor as many things as possible is a good place to start with diagnosing problems. Fuel pressure, and air fuel are necessary gauges imo. Consult is also such a wonderful tool. Being able to see whats happening sensor wise while the problem is occuring should point you right at the problem.

People arnt going to be able to diagnose for you online, my car is breaking up between these rpms. Its too vague, we need data

[r33nota240]

if all the cyl look the same like black on all cyl then i would say a maf, timing or tuning problem.

[TripleJ]

Il book it in to be retuned next week and il see how that goes