The 5K stutter cutout misfire stumble breakup Thread [Merged 7-8]

[Newlogics]

My project 92 Talon just wouldn't be nice to me.

I figured that my smoking problem was due to my turbo leaking oil, since upper IC pipe had whole bunch of oil in it.

Now more porblems arize....

1st: It wouldn't idle normally, instead it revs up to 2K and drops back to 1K every like 2 sec. if idle is adjusted to be lower then 1100 rpm

2nd: When rmp reach 5K under WOT, it hesitates violently. As soon as rpms drop a bit, it's fine again.

(The good thing I fix the unlock buttons, 'cause it had shaved handles and you couldn't get inside by any means except a trunk....)

 

[CanadianTSi]

Are you running alot of boost? If so you might be hitting fuel cut???

 

[Newlogics]

lotta boost ? I can barely bring it up to 7,
as I found out it has a HUGE bosot leak. Prolly a vac line disconnected...

 

[BatmanGSX]

You are hitting fuel cut. When you have a large boost leak the turbo spins really fast and draws a lot of air in through the MAS causing fuel cut even though most of air never actually makes it into the engine.

Fix the boost leak before you explode your turbine wheel.

 

[Newlogics]

Thanks Batman, I'm replacin the whole turbo since it's shot to sh!t anyway.

I'm really confused about that leak though. When I was doing the pressure test, not matter how hard I pumped, it just wouldn't build ANY pressure, not even .1 psi, therefore no hissing sound to listen for. So I guess a vacuum like is dsiconnected somewhere, but it must be a big one, because small ones would atleast hiss or smthn. I've tested everything up to TB, and it checks out good, so It's form Tb and on that has a leak, but I couldn't find where nomatter how hard I tried.

The engine was swapped by a mechanic that ! left MAS plug unplugged and blamed 'check engine' on bad O2 sensor !. You get the idea, how 'knowledgeable' the machanic was. SO I think he screwed up on hooking up all the lines, and now it's really hard to get to them for a look...

Can you think of any big Vac lines that could be causing that ?

 

[BatmanGSX]

Yes. The line from the PCV to the intake manifold. But you would still probably hear it if it was cracked. What kind of compressor are you using? If your turbo can get it up to 7psi then a compressor should be able to do the same unless it totally sucks ass.

 

[Newlogics]

My compressor is a manual tire pump....

On my GSX, I easily built 5 psi with it with some leaks present.
On this talon it's just not cuting it, so will have to find somehting more powerful....

I was thinking of using that CO2 pocket tire inflator (the one that uses tanks from air guns), Have any other suggestions ?

 

[BatmanGSX]

How, again, do you know for sure the leak is after the TB? I think you should use a compressor with a tank. Rent or borrow one. Don't drive your car though, or if you have to make sure not to boost at all.

 

[Newlogics]

Well, car isn't drivable anyway, it's half-disassembled in my garage (it's a project).

I've removed every component sarting with IC lower pipe and ending with IC upper pipe and pressure tested each element (pipes and IC), so now I'm down to TB....

 

[Newlogics]

btw, Batman, I got a Friend stationed in Airforce in Colorado (Colorado Springs) He had Turbo Laser, ever come across him ? Name's Vlad., white Laser RS (not anymore though)

 

[BatmanGSX]

Originally posted by Newlogics
I've removed every component sarting with IC lower pipe and ending with IC upper pipe and pressure tested each element (pipes and IC), so now I'm down to TB....

The problem with this is that leaks are usually present between the connection of two parts, not any specific part itself.

 

[Newlogics]

I realize that, but the fact that no matter how much I pump into the TB, I get no pressure build-up, so even if there might've been leaks on joints, there is still a bigger one somewhere else.

 

[BatmanGSX]

How are you pumping into the TB? Are you making sure the throttle is open??

 

[Newlogics]

I use a upper IC pipe to connect pressure plug to TB. I tried it with both, throttle open and closed. With closed throttle, I'm able to make a niddle move a notch.... with open it feels like pumping into open air...

 

[EcLiPSe 9R]

Ok I have alittle more details then my last post. Now my RPMs wonts go past 4 grand, also the engine shakes, the exhaust is moving around like crazy, and its idling below 1 grand but the car rattles. Anyone have any idea? My intercooler has some damage to it but I've been riding with it like that for about a month and the night before I was going about 130 on the freeway but besides that nothing strange to report.

 

[Run-GSX]

Sounds like something blew.........not good.
Check the simple stuff first:
plugs
wires
vacuum lines
sensor connections

You mighta blew off some vacuum lines if you were on high-boost.
Make sure the MAF is secure , and you're not getting any "false" air

 

[99GST]

Originally posted by EcLiPSe 9R
Ok I have alittle more details then my last post. Now my RPMs wonts go past 4 grand, also the engine shakes, the exhaust is moving around like crazy, and its idling below 1 grand but the car rattles. Anyone have any idea? My intercooler has some damage to it but I've been riding with it like that for about a month and the night before I was going about 130 on the freeway but besides that nothing strange to report.

This happened to a friend of mine recently. I opened up his hood, and wiggled his IC piping. Bam, I practially pulled it off from the TB. So, check all of your intake pipes and IC pipes, that could be your problem. If there is a major leak, then it will give you a very low idle and the car will shake bad.

Nathan

 

[Wicked91rttt]

Ok, my other friend is getting a 91 TSI and it is overall really nice. The only thing that we found wrong was that everytime at WOT when it hits 5000-5200 RPM it stalls for a second, then 2-3 seconds later (while still holding pedel all the way down) it picks back up and goes. I have a datalooger and the only thing I noticed was a DEAD o2 sensor reading, knock was at most 5 counts. and timing looked good. Do you think it could be bad plugs and wires? ( The wires look a little old but we didnt check them or the plugs) ANY sugjestions?

THanks a lot everyone.

Brett

 

[Wicked91rttt]

ttt

 

[1994supertalon]

Definatley try replacing the plugs and wires. I've seen other cars do simular things and new plugs and wires almost always clears up the problem.

 

[eclipx]

^^ yeap

 

[echo]

when i first started driving my car after the year it sat up. i took it to a shope to have a tune-up and they put in bosch plugs out of the box. they didn't gap them or anything. they had the car running with the timing belt cover off and it nicked my wires ( i didn't notice till later). i kept thinking the car didn't see as fast as it did when my dad drove it. it was also bucking really bad. so i thought maybe they didn't do a good job with the plugs. i ordered the bpr7es ngk plugs and a set of magnecor plug wires. i installed and took for a test drive. it fixed it 100%. i was able to feel it pull hard all the way to redline.

 

[DSMafia]

ok guys I have no pull about 5K.... i mean it will rip you eyeballs out from 3800 to about 5K then it just seems like it runs out of steam or something....boost gauge still reads 1.3bar, but sure as hell doesnt feel like it..... I've adjusted the safc every possible way you can think of and still doesnt make a difference, well other than inducing fuel cut a hell of a lot sooner. Ran some logs and I'm running. between .9-.93 all the way through the power band, so I know I'm not running too rich.... I've checked all piping for leaks, spark plugs and wires are good, injectors are balanced and pulsing fine, basically the only thing I can possibly do is clean out the TB.... any suggestions.....oh let me add that I have a profec A with some really fuzzy fuzzy logic.... I'm thinkin it needs to go in the trash, but could this be causing the loss of pull?

 

[L2RTSiAWD]

Looks like it's time for some cams.

 

[DSMafia]

I thought cams only helped on bigger turbo apps, all the charts Ive seen, cams really dont make a big difference on 16gs and smaller?