car building boost, but no power

[super97gst]

my gst has been having this problem since i bought it. it quit for about 6 months though and now its doing it again. i have tried everything i can think of to remedy this problem and searched all over this forum to no avail. heres what its doing: sometimes when i take off in 1st, not running it hard really either. the car will build boost just like normal. jumps right on up to 17 or 18psi, but the car just barely moves. and im not talking bout a clutch slipping either. the car mostly does this when i take off from a dead stop in 1st gear. it just feels very sluggish when it does this, thats the only way i know to explain it.

well thats all i can think of right now about the problem. if anyone has any ideas i would really appreciate ur input. thanks

 

[2GeNTSi]

Saw on another thread that the car runs fine now with 3g lifters...congrats. I'm still searching for an answer, gonna do that leak test and then maybe take out my knock sensor...hopefully it's not too difficult to remove.

I don't think I'm getting phantom knock because my lifters don't tick at all lately. But this no power doesn't happen occassionally but pretty much anytime...doesn't matter if it's warmed up or not, cold or hot outside. My log shows a couple degrees of timing being pulled but can only a few degrees make that much of a difference?

 

[Spyydie98]

Did you ever find your problem? I've been trying to eliminate my knock issue that has been plagueing me for awhile now. I just redid my lifters, the MCCC treatment, a new knock sensor today and I got it to act up again. I'm looking for all the different solutions people have found.

 

[2GeNTSi]

I'm still in the dark with my timing problem-I'm getting to that point where I don't care. I already got a new 2G Knock Sensor put in, I'm going to do another log after I put my 3" downpipe back on. I don't like doing many runs so I try to keep it to a minimum. I know I'm running quite rich for whatever reason, but it's been pulling timing before it started running rich. I'm sure that's not the main factor, but it probably is contributing to the timing somewhat.

I did a boost leak test not too long ago, and found some small leaks at the IC inlet and oulet, fixed those. There is still a pretty bad one at the TB, researched that and found out that it is the o-rings that are worn. I might just buy an aftermarket TB with new sensors and everything rather than just replace the TB itself. Other then that, no leaks. Compression was 165 across without warming up the car-within spec, though, my impression is that my compression numbers would be higher if it was warmed up due to the piston rings expanding. Is this correct?

I used Redline Complete Fuel System Cleaner some time ago but didn't notice any difference (fuel filter is new as well), put in a new o2 when I swapped the T-25 out for a 14B, and had timing done a few months ago. My next step is to just buy DSMLink (expensive I know) but that is the only thing I can think of. This way I can actually see how much knock I'm getting-adjust the ignition accordingly and what not.

DSMLink won't come until I get another job, in the meantime I'll just log some 3rd gear pulls. I just adjusted the byte timing so I get 11 b/sec now, it will be much easier to see what's going on with my car now as opposed to 6 b/sec.

 

[Spyydie98]

Sounds like a lot of us are having fun with this. I can't confirm mine is PK with my 2G, but I do know I get timing pulled (sometimes, but only starting under 3k or so) from logging and my symptoms are that of PK or real knock.
I replaced my lifters last week and did the MCCC thing with new oil change. Damn, if the car doesn't run smoother and purr! But, I still managed to get it to do the "2-3k pull timing" thing once warmed up - intermittently - not every time.
Well, my next step was a leak test. I put everything together today with parts from Home Depot (they actually sell a plumbing coupler for ~$4 which is the rubber hose with the two clamps).
I didn't think I had a leak since I had no problem getting the 14b to hit 15psi. I was wrong.
During the test (I tested it cold - don't know how much it matters), it was leaking at the LICP into the IC with only a little pressure. Fixed it. A little was coming out of the BOV flange - fixed it. I plugged up the hose that goes from the valve cover to the intake and no other leaks were heard until I hit 15psi - that's when oil started to come out of the oil filler cap. I put everything back together and I'll say that it idled smoother for sure.
I drove it around for a bit and it drove great so far. Crossed fingers.
I'm curious. I've got three theories. IF (and only IF) my "timing pull" issue goes away as a result of fixing boost leaks.
1) Theory one - Timing pull as a result of intake track leak.
If you drive around between 2-3k rpms with a leak, then that could cause a rich condition to slowly build and then when you get on it, you bog\knock (since knock count goes down slowly and not at once, timing pull continues up the rpm scale - unless you let off and then when you get back on it, you've "cleaned out the chambers" an the timing is there, because you're not rich anymore?
2) Theory two - Timing pull due to result of intake track leak but a different scenario.
If you have a small leak that begins on its own while cruising (under vacuum) sometimes in the 2-3k range and when you go into boost, the leak gets worse = rich = timing pull. You let up and get back on it, but the leak doesn't reappear the next time you get on it. Not sure - seems like "once a leak, always a leak".
OK. My third theory is if and when my issue goes away, I'd be happier than a pig in @#$%!

 

[DarkEagleTSi]

I'm not sure if this is the right place off my problem but here I go!
No Leaks. Boost builds fast. Plugs and Wires are New. Freshly Rebuilt motor. New Injectors. New ECU. I was in the process of breaking in the motor. I had put 400miles when I decided to stop babying it so much and start pushing it a little more. Changed the Oil & filter and proceeded. I could not get the motor past 4000RPM. I was scratching my head. Consulted with the engine installer and the engine builder, but they were also clueless. I needed the car for work so I drove it for two days under 4K. I noticed that my Air/Fuel meter showed a Lean condition 75% of the time. On the third day, the car wouldn't go anywhere. It Idles just fine (750). It does not go though. Runs like it is overheated. No power whatsoever at anytime!!! I was able to get it home by fluttering the gas pedal. Lightly on, then off, then quickly back on, then off, then again and again. The car started running again like nothing and the A/F showed stoich and rich. ????????
At home in my driveway I noticed that my vacuum is very poor, like 8in/Hg.

What the HECK??? Please help me!!!

 

[Spyydie98]

Since your power got worse and worse and you babied it for a few days and didn't see an issue until you started to get on it, I suspect a leak has began.
When I changed out my turbo it ran great, until a hose popped off. Then I got nothing but idle. I recently found out from experience that you can show boost on the gauge and still have leaks. Since the leaks are after the turbo, you lose air that the engine is giving fuel for. Of course that would make you run rich.
Anyway, since you just did all this work, maybe a leak is getting worse? Just because tubing seems tight still doesn't mean no leaks.
This doesn't explain your lean condition, but can explain why you can't get more than just an idle.

 

[DarkEagleTSi]

balance shafts were out of phase!
sorry 4 delay. thnx guys