Full boost lose power!!!

[NADude98]

Help! I have a problem. I was getting on it pretty good the other day and at full boost I felt a strange sensation, like a shudder.

Since then when I get on it when I reach full boost, it like cuts out or sputters and loses a little bit of power. First thing I looked for was vacuum leak, like I had blown off a hose.

Any ideas or places to start troubleshooting would help!!!

 

[s383mmber1]

Are you talking about fuel cut?

 

[7m2bar]

Sounds like you are in for a new set of plugs mate! What boost are you running and what heat range of plugs?

 

[supra_ed]

do a vacuum/boost leak down test

 

[Poodles]

boost leak or ignition issue...

 

[NADude98]

Are you talking about fuel cut?

No, this is not fuel cut!!! I am running about 20lbs of boost with Lexus MAF and RC 550's. Also I just changed plugs a week ago, I haven't checked them since but that is why I eliminated them in my mind as the problem. I am running the NGK's that it calls for. The 6's

 

[suprahero]

What are they gapped too? With 20psi of boost, you may need them gapped to .028 instead of the .032 they come with. I'd pull them and see if you fouled one out, and make sure everything is grounded good also.

 

[super.secret.supra.club]

imma keep an eye out for this thread. i always run into this problem. i change out my plugs once a month. good thing they're cheap.

ed.d.

 

[starscream5000]

Did any codes come up once this happened?

I'd say boost leak or ignition.

 

[7m2bar]

Id say try a set of 7 heat range iridium NGKs and take it fom there. With 20 psi you should run 1 step colder. I had that problem with 17 psi on an iuprated ct26, changed the plugs and it did the trick.

 

[super.secret.supra.club]

coppers...

 

[starscream5000]

Love coppers, cheap and easy to gap where you need them to be.

 

[wardog]

Guys I have the same problem too, it sputters at high 5000-6400 rpm. Were do most of you guys get the Ngk 3330s none of the autozones have them here in Houston,tx. I didnt mean to hijack your thread man its just that i have the same problem.:1zhelp:

 

[HommerSimpson]

hell mine spits and sputers at 8-9psi guess i need new set of plugs to..

 

[super.secret.supra.club]

and i thought i was the only one having this problem. i know for sure that its the plugs for my car. last time i replaced mine, 5 of the six plugs had hair line cracks on them. i was using heat range #6. its ok though. i check them constantly now and replace them once a month to be on the safe side. copper plugs cost me like 10 to 12 dollars at my local autozone.

the feeling that i get is like a spit/sputter at about 4 grand and up. you can feel the car haul ass in 3rd gear until 4 grand. then it just feels like the motor is taking a shit.

ed.d.

 

[wardog]

I feel your pain brother :nono:

 

[suprahero]

Guys I have the same problem too, it sputters at high 5000-6400 rpm. Were do most of you guys get the Ngk 3330s none of the autozones have them here in Houston,tx. I didnt mean to hijack your thread man its just that i have the same problem.:1zhelp:

Tell your local parts store to order them for you. They'll have them the next day.

 

[Poodles]

maybe it's going too lean or rich as well?

 

[super.secret.supra.club]

well ive got wideband hooked up and logging it. it shows that i run below 9.6 AFR when under hard excel and boost.

ed.d.

 

[suprahero]

That's way too rich. Do you have a way to lean it out to about 11.2 under wot?