SR problem (still)

[Brandon]

Ok, I posted about this before, but the post is old and I don't want to bring it up. My problem now is when I hit boost, my car will bog and backfire and misfire. The popping it makes from backfiring sounds like it's bubbling, but it will backfire normally too. I can drive no problem if I don't hit boost, but it'll pop and the revs will jump around alot and want to die or sometimes will die, but only when the engine is warmed up.

I've checked timing, all my vacuum lines, IC piping, and replaced my spark plugs recently. I've been told it could be my MAF, I am going to be checking the voltage of my sensors tonight with a voltmeter, but beforehand is there anyone that could possibly shed light on the problem.

[DataXUnknown]

Try moving the injectors around, they may be clogged. My car sounded like a subaru for a lil while then I played with the injectors a bit and it fixed it. So I'm probably just going to replace them.

[landins13]

if you are getting the correct voltages buy MAF cleaner and use that, my car had a similar problem i cleaned the MAF and poof all better.

[all show no go]

Try moving the injectors around, they may be clogged. My car sounded like a subaru for a lil while then I played with the injectors a bit and it fixed it. So I'm probably just going to replace them.


i agree. get em checked, they may be leaky or clogged.. my car had a way rich mixture and was also very boggy.. so i switched em out, and then it ran fine.

[Brandon]

Well, I was driving it today and for some reason my cold pipe came off and the car idled perfect, but misfired (as would happen when IC piping comes off) when I drove and didn't go above 2500rpm. I checked the injectors, I was considering just replacing them all and getting a new fuel rail because they won't come out at all. My friend sprayed the MAF with carb cleaner the other day, which I dunno if that's good or bad.

[sr20det drift]

ignitor chip? check that with a voltmeter, get 2 people. this sounds like how my car sounded.

[Z U L8R]

boost leak

Dave =]

[SDS13COUPE]

Well, I was driving it today and for some reason my cold pipe came off and the car idled perfect, but misfired (as would happen when IC piping comes off) when I drove and didn't go above 2500rpm. I checked the injectors, I was considering just replacing them all and getting a new fuel rail because they won't come out at all. My friend sprayed the MAF with carb cleaner the other day, which I dunno if that's good or bad.

Defineately sounds like MAF. Try swapping with a friend. Also check your wiring for it.

[dori_sil8t]

what maf are u using sr or sohc ka?

[((sr)) kelly]

how much boost are you running?

[axiomatik]

I had very similar problems when I had a boost leak.

[Brandon]

I've checked all my IC piping, no leaks. I'm running 13psi right now. I believe it's the SOHC KA MAF, but I'm not 100% sure. This car has had problems with vacuum nipples falling off/apart and causing problems before, so I checked everything related to that, nothing is wrong there. I'll recheck my piping and see if there's a leak that I didn't notice.

[180sx-sweeet]

boost leak, way rich or extremely lean... lol have you checked on a wide band yet?? what is your set-up? change your plugs!!! you'd be surprised... don't use platnums whatever you do though!!! turbo cars don't like em

[SexPanda]

Try moving the injectors around, they may be clogged. My car sounded like a subaru for a lil while then I played with the injectors a bit and it fixed it. So I'm probably just going to replace them.

thats not a clog. thats a short. one of your injectors just wasnt getting power cuz of a bad connection.

same thing happens with my car. old ass wiring, old ass car.

[Brandon]

I'm using NGK Iridium, BKR5EIX. I've been checking my IC piping and anything that could cause a boost leak and it's all bueno.

[Z U L8R]

i don't think plugs are ur problem at all, but for a boosted car those are hot ass plugs. you need to go with like bcpr7es @ .028 gap , or bkr7e @ .028

i still think you have a boost/vacuum leak. typically all is fine until you get 1 lb of boost, as soon as u boost it starts wigging out then that's ur issue. when your car is fine but can't rev passed 3k then that's a maf problem.

Dave

[Mi Beardo es Loco]

MAF or boost leak

[dorkidori_s13]

what fuel pump are you running???

[180sx-sweeet]

bcpr7es


yay FTW.... good call, same thing i'm running! beautiful plugs... add a bit of gap though .033 :bigok:

[hstylez]

My vote is on boost leak. I know you said you looked but they are easy to lookover..

[Brandon]

I'm running a Walbro 255LPH

[Z U L8R]

try to tighten all the clamps

fwiw
bcpr7es come gapped at .030 unless you get the bcpr7es-11 *the -11 means they're pregapped to 1.1 aka .044. if you're running stock boost you won't blow out spark at .030 gap, but if you're running 13-14psi .028 is what u need. i was running 22psi /w no [email protected]

Dave =]

[Air]

boost leak means the idle will be horrible too..

im having the same issue and i dont know how to solve it. im thinking the wastegate is on its way out

[Onitsukagirl]

check that fuel pressure, my sr ran like crap before I got a FPR. Backfiring and all that..

[S14DrifTmATic]

+1 on MAF...

[Air]

How would i go about checking my fuel pressure?

could my FPR have gone bad? is this a hard item to find in the us or to replace?

[Brandon]

Rechecked all my IC piping and vacuum lines again, all bueno. I'm going to be replacing my MAF on Friday and will see how that goes.

[Brandon]

Ok, just took it out for a drive today. Problem is really only under boost or when I floor it at all, it'll idle funny and stutter when I take off or go below 2k and try to speed from there, it'll also misfire and stutter. At idle the AFR is around 14, which I think is pretty rich for idle, leaky injector or MAF?

[powersteeringless180sx]

yea like everyone else has said. check you maf and injectors and check the wiring for any short and disconnected wires. is your ecu throwing code?

[Brandon]

ECU is throwing a code 55, no problems. I've checked my injectors and am getting a new MAF.

[Z U L8R]

leaking injector grommets is a boost leak, is a fucked up idle scenario, and also will still pull an all systems good code 55, great point @ brandon
gl :)

[fbiphil]

I had an alternator go out on my KA, and as the battery died it would idle and drive slowly OK, but would stutter and misfire if I went to WOT. Check your charging system to see what kind of voltage you're getting at the battery.. just a thought!

[duffman1278]

How are you checking for boost leaks? Please don't say visually. If you havn't done so yet, build/buy yourself a boost leak tester, their inexpensive, and quite useful.