Studder under boost

[rbveilside240]

Hey guys, me again--when i turn my boost up, around 9-10 psi a studder develops. I have checked all the lines and there is no leak.? What could be the problem?

[Slo_240sx]

Boost leak somewhere. Recheck your I/c pipes... You also might be maxing out the MAF.-Alex

[rbveilside240]

so you think I need a new MAF if that is the problem or will a AFR fix this?

[klh6686]

do you still have the stock turbo? if so i highly doubt you would be maxing the maf out, but if you have an upgraded turbo its possible. The easiest thing to check first is to make sure that you have some quality ngk plugs in there and that they are gapped properly. Factory they come 1.1 mm but it is recomended that you get .8 mm for higher than stock boost. Good luck.

[rbveilside240]

Got brand new NKG type R plugs. How do I know what the gap is?

[Joe]

you check with a plug gapper

99 cents at autozone

[JonPowell]

Your timing may be too far advanced for that amount of boost also...you may be detonating and the knock sensors are pulling timing on ya.

[rbveilside240]

I havent had a chance to check the spark plugs nor the timing, but today I found that there is no studder if I let the boost build up at half throttle, but when I press the petal to the floor, it begins to studder....Any more thoughts?

[JonPowell]

Same thoughts, try what we suggested first, then look for more options.

[rbveilside240]

guess it was the spark plug gap,it was sit at 1.1, I gapped it a .8, took her for a spin and it studder a couple times, then hasnt done it since----THANKS GUYS