Addicted To Boost Posted July 7, 2008 Author Report Share Posted July 7, 2008 bad vacuum modulator? How do I test that? Are they pretty cheap? I might just swap it out if they are relatively inexpensive. Quote Link to comment Share on other sites More sharing options...
krenzy Posted July 7, 2008 Report Share Posted July 7, 2008 Nick, they're like $18. Not the easiest to do, but nowhere near difficult...just in a bad spot. Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted July 8, 2008 Author Report Share Posted July 8, 2008 UPDATE I just stopped by the local GM dealership and had a mechanic come out and take a look at it. Bad news: he said that it sounds like my turbo bearings are on their way out. He said "it will be fine to drive it, but it will probably go very soon, and when it does, the turbo will lock up and the car will smoke a lot." It was funny when he was checking out my car, another mechanic walked up and checked out the car, he left for about 15 seconds and four other people came out and checked out the car. I had just polished and waxed and put paint sealant on the car yesterday, so she's pretty shiny right now. So I got a lot of compliments from all the people at the dealer. Quote Link to comment Share on other sites More sharing options...
AWeb80 Posted July 8, 2008 Report Share Posted July 8, 2008 If I had a TGP, I'd just stop at the dealer just to show off.....LOLZ ....you should see the way they flock to my GP the way it is.......(*ooo, clean car for a trade in*)....<----that's what they always ask me Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted July 8, 2008 Author Report Share Posted July 8, 2008 If I had a TGP, I'd just stop at the dealer just to show off.....LOLZ ....you should see the way they flock to my GP the way it is.......(*ooo, clean car for a trade in*)....<----that's what they always ask me Fun, isn't it? So.... its time for a new turbo. I would like something that will bolt up with little to no modification (unless its worth it ) What is out there that you guys recommend? A buddy of mine knows a guy that can get hands on almost any turbo inexpensively. GTR2871? T3? T3/T4? I would definitely want to have a ball bearing turbo to go in there next, unless I can find another T25 for dirt cheap. What do you think? Any input is appreciated! Quote Link to comment Share on other sites More sharing options...
AWeb80 Posted July 8, 2008 Report Share Posted July 8, 2008 GT35R....might be a tad big....I know it works well w/ 3800's.....although a guy in town locally is using it on his Starion....thats only a, what, 2.5L (?) 4 cylinder..... Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted July 8, 2008 Author Report Share Posted July 8, 2008 I replaced the vacuum modulator today with a new one. Turns out that the one that was in there before was an adjustable one with two red stripes on it.. and it had a bunch of gunk in the vacuum inlet, so I'm thinkin it may have been leaking a little bit. The new one is another adjustable vacuum modulator, but this one has two black stripes on it. By Brian P's advice: http://www.w-body.com/forum/index.php?topic=69578.0 I adjusted it to 1 turn in clockwise from the aftermarket modulator's factory setting. It seems to be shifting a bit better now, it doesn't slam into reverse very hard anymore, and the car doesn't shift super late at low throttle settings (before it would just hang in a gear at ~2,500 for no reason unless you let off the gas, then it would shift). So its getting closer to the way it functioned last year. I am still hitting fuel cut before it shifts at WOT though. If I let off to ~7/8 throttle, it will shift however. Before with the old mod, you had to let off the gas almost completely for it to shift. So it is better, but not quite perfect yet. What do I do next? I tried adjusting the TV cable before: depress the square button and push the cone shaped cable end back inside the button, then go inside the car and slowly floor it while the cable clicks and adjusts.. Am I not doing it right? Whats the deal here? Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted July 9, 2008 Report Share Posted July 9, 2008 whats all the   stuff in your post? anyway, you press the square button in all the way and hold it, then take the throttle linkage with your other hand at the tb and open it all the way, that should adjust it right. I like it to shift as soon as possible. I got one that shifts in to second before I even get around the corner and going straight. Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted August 6, 2008 Author Report Share Posted August 6, 2008 Update The car has been running pretty well since I found my vacuum leaks and fixed them. It has been feeling somewhat weak during heavy acceleration though. Did a bit of work on the car today. I pulled the Hot Tune chip out and put in the stock chip, to see if it would make any positive changes, but it didn't, so I put the Hot Tune back in.. I did a fuel pressure test today and I had ~36 PSI at idle, and a wierd thing happened. When the engine was off, key on, it would prime, but then the fuel pump relay would click and it would stop. I was reading ~7 PSI at the rail with just the key on. So I replaced my fuel pump relay with a good one and it would prime up better, but then it would click soon after, and the pressure would spike down to 7 PSI. I had my neighbor looking at the pressure gauge, so I don't know how high of pressure it built. So he was thinking that I might have a bad ground around my fuel pressure relay since it was clicking and not building pressure.. or if that is normal to click like that, he thinks that my fuel pressure regulator may be bad/leaking and sending too much fuel back to the fuel tank.. or maybe my pump is going bad.. I am not sure what is up here. I did pull the vacuum line off the FPR and it was dry.. no fuel is leaking into the vacuum lines. I took the scan gauge out and went for a drive with it. My 1-2 shift is very good, nice and firm but not jarring, and it looks to shift pretty consistently at 5,120 RPM, the highest I saw was 5,300 at the beginning of the drive. My 2-3 shift however is not good. It will rev out to ~5,050 RPM, then sit there and stutter like it is hitting fuel cut.. I have to let off the gas a bit for it to shift 2-3. For you tuners out there, I have some questions for you. My block learn moved around.. is this normal? It was 128 for a while (which I thought is normal), then it went up to 131 for a while, then down to 125, then to 121. Also, I went to Knock Retard count on the gauge and it sits at 0* during regular driving, but when I gave it full throttle and went into full boost, it started reading up to 10* and higher.. IIRC it went over 20 once too... I dont know if this is right or not, I was thinking it would go in negative numbers if I was getting knock.. I don't quite understand how that works. Everything else that read on the gauge (that I understood what it was) looked to be okay. I also did a few 0-60 runs, and I timed a couple of them with a best of 6.6 seconds. It was very humid out with kinda wet roads, and I lost traction for 1-2 seconds and squealed the tires. The car seems to be running decent, but it just feels weak when you start getting up there in RPM's.. like it isn't getting enough fuel or something. It is very quick if you drive at 1/2 throttle though. What do you guys think? Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted August 7, 2008 Author Report Share Posted August 7, 2008 I should also add that the car has been starting REALLY hard lately- it usually takes 5 or more cranks to start it. Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted August 7, 2008 Report Share Posted August 7, 2008 thats annoying sometimes. one of my black ones does that. It runs good though, and it just helps prime the motor with oil anyway. I dont know what to do about it though. still getting 6.6 though so not all bad. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.