hope you guys can help, I thought that my car was just acting up becuase all I had on it was the down pipe, it would stumble at 4,000 - 4,7000 rpms now that the exhuast is welded together on the car ( I am asuming that is what it is) it won't rev up past 5,000 no more stumbling then rev just bogs out or something, any ideas on what it is??

Thanks, Jason

could it be the timing not advancing?? it starts out fine, but as I do a steady rev it starts to spark after tdc?? anyone help please

Hahaha...your describing my problem. I cant rev past 5k either even idling. This is only after i changed my pump. When i lean it out with the afc it makes it worse at 9 psi but somehow it hauls arse at 15psi and revs to 7900...so since that i just race at 15psi now and cruise at 9psi. Timing should be at 15 by the way...its 20 for the Gti-r ecu cause they run 100 octane i guess but for jwt one its 15... Prettywhite told me a car dynoed at 17 degrees and 15, at 15 it gained 20 extra horses.

so just turn the boost up, and problem solved?? what is 17psi converted to kg/cm thats what my controler reads, but I also smell gas coming from the valve cover could it be timing?? please help guys thanks.

Same shiet here. The oil smells like gas for some reason after a while of driving... Its like its contaminated everytime. I have to change oil every 1k just to be safe. Well thats my case...i use the AFC and have the fuel decreased by 7 percent from 5k up and now it pulls, no more backfire or anything. 17psi should be around 1.2bar? Im guessing but its around there but you shouldnt boost up until you have an upgraded fuel pump by the way.

I did upgrade the pump but the sum blotch stil runs lean, maybe thats the problem, it ran fine at the higher boost, but then all of a sudden it runs really lean, and acts like the car is off, until I hit 2,000 rpm, and then I drives normal but can't go any higher than 2,200 the air fuel guage is reading lean and then really lean.

Make absolutely sure that all of your IC piping is connected tightly with no vacuum leaks. My car wouldn't rev past (guess what?) 5K rpm. Sounds eerily familiar with what I was going through. The IC pipe feeding the intake manifold was ever so slightly off causing my problem. Recheck all of your connections and let me know if this solves it. How is your idle?

the idle is very irratic, and it runs lean, I think i'm going to run a pipe in place of the intercooler and see if that helps (my intercooler has a dent, and think it might be leakin).

Nx-t...your problem sounds like what i had before. The idle jumps from 600-900 and would never be steady at all and it would not rev up cause it was too rich. For me the plugs are always black and if i idled too long it would foul out the plugs so i would have to take them out and clean it. To solve it i had to buy the afc so i could lean it out. My a/f values are around .89 with it leaned out 18 percent from 1k-3.5k and high rpm it gets to .93 which to me isnt that bad as it runs the best this way.
So did it rev higher when boosting up? Are you running the det distributer? It might be lean cause of the 20 degrees timing your running, lower it and then check your plugs...what color are they?

I knew either it was a leaking silicone/rubber coupling IC pipe connection or some other type of leak. I swear it was like yesterday (or last year) when I was dealing with it. It was a hairline leak where the IC pipe wasn't perfectly aligned with the silicone hose. Let me know after you perform that test to see what happened.

okay I bought some hose and ran it across there, and it idled a little better still reved funny though, drove it around and is still stummbled alittle but not like before, then about 15 minutes into the drive it started acting up again really bad, could go past 2,500 rpm. noticed when I don't floor it would go over the hump were it used to stall out at alot better, but it is runs lean already, and you are saying it is rich to lean it out correct? my plugs are coated in black carbon cleaned them and put them back in yes it runs better with the boost up. timing has been adjusted to 15 degrees as of this morning.should I get an fuel pressure regulator or safc or some thing like that?? just about willing to try anything. just want it to run right, hope I got all the questions,if not please ask again I will anwser.

Thank you, Jason

I know for me it cant be the intercooler hosing. I still run the top mount with only 2 hoses and i ran the 2 hoses lose by accident before, and it feels exactly the same. If its full of black carbon you should be rich, not lean. I dont even have an a/f gauge so i just look at the a/f values of the afc to tell. What plugs do you run? I currently run the iridiums and noticed it smoothed out the high revs as well as better fuel economy. If you have anymore questions just shoot but im not an expert and just trying to help.

I think I am goin to get an afc, my air fuel ratio guage could be wrong, I don't know so, I am running ngk-r plugs, I think I will change them to some thing else, and also cang the sensor on my air fue ratio guage ( it is all sooted up also). thank you for all the help, I will let you know how it is runnig, also the car seems to be putting out some black somke from the tail pipe, is that because it is running lean or rich??

ttt

To me black soot was always being rich... but its your decision on the afc. I know its helped me and i tried calling JWT for technical support and all they said is that we cant help you, you did something wrong it cant be our fault...to make it worse the guy was like we have other customers here so i cant spend time chatting w/o you. So the afc was my only resultion. As for the O2 sensor, i just sprayed it with intake cleaner to clean it off.

Originally posted by SucKit
Hahaha...your describing my problem. I cant rev past 5k either even idling. This is only after i changed my pump. When i lean it out with the afc it makes it worse at 9 psi but somehow it hauls arse at 15psi and revs to 7900...so since that i just race at 15psi now and cruise at 9psi. Timing should be at 15 by the way...its 20 for the Gti-r ecu cause they run 100 octane i guess but for jwt one its 15... Prettywhite told me a car dynoed at 17 degrees and 15, at 15 it gained 20 extra horses.

No way, it was way more than 20hp. Ask Redman007 when he comes on. The car dynoed at 160something then when he backed down the timing it went up to over 225. Unbelievable! This was at Ray Kawaski's Dyno Day 2001.