Somebody help please, my car bogs when I hit WOT

[red s13]

When I drive around town at part throttle the car runs smooth, but when I hit wot it bogs and doesnt pull hard. I made a boost leak tester and found a few leaks,but I fixed them and it still has the same problems. I have a t3/t4, s-afc2, recirculated bov, z32 maf, and my timing is set to 16btdc and im runing 8psi. Iv tried gapping my plugs down to .028 and still nothing. If anyone has any soulutions please respond.

[KATwo40]

What are you AFR's at WOT? Did you replace the plugs? Have you run any kind of fuel additive?

[red s13]

Under boost my afr is 11.5 to 12 and under part throttle its about 14.5. Yes, i did change the spark plugs to ngk bkr6e-11. This problem is wierd because it hits and hold 8psi, but dosent pull hard and when it hits wot it just slows down even more.

[emperor_lunchbox]

my car does someting similar. People are telling me its the IACV. I don't know if that is true or not, but, thats what they tell me and I have similar symptoms.

[red s13]

I dont think its the iacv because my car idles steady at 750 rpms and runs smooth it just laks power and hesittates at wot.

[emperor_lunchbox]

i could be wrong, but shouldn't it idle at 900-1000I dont really think its the IACV, but our problems are so close and it looks like thats what my deal is.

[red s13]

My problem feels like its a boost leak that I cant find or a bad sensor thats causing my computer to pull timimg once I hit wot.

[Jookmasta]

could be ur stock coil. id say try an msd coil and see if that helps or gap down the plugs even further. check the grounds on the maf and on everything else.

[danb8586]

maybe your tps is bad

[S14tat]

if your breaking up from a spark miss it would show the car running on the wide band. when you have a boost leak, it would show rich on the wideband. so try lookin at it again. when it starts breaking up the moment it happens, what does the wideband read?

nissanfanatic had a problem very similar to this a while ago and it turned out to be a bad coil.

[red s13]

I already have the msd blaster coil, and how much smaller of a gap could I possibly go?

[red s13]

Ok, I checked out the lm-1 today and when I hit boost it runs really rich to 10.9 afr at about 4k rpms leans out a bit to 11.5 then runs rich again at about 5500rpms. Could a bad o2 sensor cause my problems? Today I noticed that the wire on the sensor has broke a little.

[S14tat]

o2 sensor doesn't do anything at WOT. only low throttle and idle. hmmmm a 11.5 is not lean enough to be considered a misfire. you could try to redo that wire on the 02 and see if it does anything, since it doesn't hurt and it has to be done anyways.

[get_up_mark]

sounds like the at wot throttle ur spark is being blown out. are the plugs 1 or 2 stages colder?

[shockload]

my car has been doing this crap in cold weather

[Mishka]

Is ECU throwing you any codes? Is your CheckEngineLight on? Even if not ECU may still have some trouble codes stored in its memory. I had bad knock sensor, and the driving impression was very similar to what you are describing.

[red s13]

THe ecu is throwing a code but its just the egr it comes on every now and then. How do you test the knock sensor to see if its bad or not?

[Mishka]

If the ECU doesn't give you any trouble codes for KS, then it is OK. Just make sure that EGR is the only code you are getting.I've heard about resistance check on knock sensor, but i'm not sure how to perform it exactly. Simple visual inspaection will give you clue. If plastic is cracked replace the sensor.From a dealer it's about 150.00,I have bought mine from e-bay for 78.00 shipped.

[red s13]

I fixed the problem today it turned out to be a leaky vacume hose and a intercooler coupler. It would leak bad causeing me to run rich and bog under full throttle, but now that I fixed it runs strong. Thanks for the help.