SleepinOnBoost

My car seems to sputter full throttle about 2,000 and just doesn’t do a thing from there. When I give it half throttle it breaks and sputters up around 2,000-4,000 rpm and boost as usual. I would like to add that I have stage 2 264 crower cams in my sr20det. I have been hearing a spark knock between 2,000-4,000 rpm, also like to add that it goes away after those rpm’s. Also when my car is in neutral revs up fine all the way to redline. Also my car seems to miss at idle when it is warm but it might be because of the cams. I have done the following already to see if it was the problem:
-Replaced CAS
-replaced igniter chip
-changed oil and plugs
-replaced vacuum hose but as from what I hear it could be something else causing a vacuum leak
-Reset timing
-also reinstalled cams thing it was an installer error but the car ran fine until a couple of days ago
-Also I put a new timing chain tensioner on it think it failed and caused my car to skip a tooth
-Checked to see if my ecu was throwing codes and it not throwing a single thing
-Tested to see if I have bad coilpacks
-Compression came out fine
-Checked ground and made shure battery terminals wire secure

B-Well

make sure all your charge pipes are securely attached. and that your maf is in good working condition

hottscennessey

Sounds like MAF to me.

What do your codes say?
Checking codes:
http://www.240sxforums.com/forums/ni...ieve-them.html

sumospeed.com

yes disconnect your MAFS with the car running, if nothing happens you have a bad MAFS. thats what it sounds like since you tried everything else. also make sure all of your grounds are connected and that your battery has a good connection.

SleepinOnBoost

i talked to you the other day scott im still lost and i know how to check the codes and none are being thrown...

SleepinOnBoost

also i have checked all the grounds and my battery connection i just forgot to list it

SleepinOnBoost

Ok I unplugged my MAF sensor; it died down, and went back to idle and idled the same as it did before it was unplugged. Also this makes me believe it isn’t the MAF.

sumospeed.com

the only other little things i can think of are make sure you dont have any boost leaks anywhere (couplers, wastegate line, etc...) and maybe make sure your plugs are gapped correctly? the plug thing is slim to none but just something else that came to mind. what fuel pump are your running?

SleepinOnBoost

Brand new walboro 255....and my injectors are fine I honestly think it’s an air problem too much or too little. I reran my waste-gate too intake line and that’s it, and I’ve checked for leaks in the other lines but I haven’t checked my intake manifold. But a vacuum leak doesn’t explain bucking and jerking. I'm baffled NICO said it’s a vacuum leak but it doesn’t make a whole lot of sense. I’m wonder if something is sucking in ones of the lines because sometimes it will boost fine and other times it won’t.

sumospeed.com

did it always do this or was it an all of a sudden thing?