Boost spike (with other problems)

canuckwrx · 07-09-2008, 01:33 AM

Hey All,

Well I have a 2002 and Basically I got ripped off when I bought my car and its worth more to me to drive it off a cliff than to sell it. I'm Just trying to get the car to a nice driveable condition. It's stock except for turbo back catless. K&N and silencer removed. I Just installed a boost gauge so I can see whats going on. At WOT the boost is spiking to 19psi and falling to 10 or 12PSI in a pulse. While the boost is falling the RPM climbs rapidly and the car doesn't seem to accelerate to match the RPM increase. When the RPM falls off the boost picks back up and the car accelerates. This is on stock turbo no boost controler. I have had a code for the last year for the O2 sensor. But now from what I understand I have a misfire as the CEL is flashing after WOT, and it idles like a bag of hammers. My initial plan is to change plugs and fuel filter. Swap coil packs. Buy a tactrix cable and find some free software so I can see what's happening in there. (and maybe tune some of this out) I was planing on changing the timing belt as it just hit 90K But after looking into it I'm gonna pay some other poor sap to do it. If this doesn't work that cliff option might come in handy.

Am I on the right track?

Oh yeah I'd like to find someone who can pull the code or if there's a way I can flash the DTC on my odometer????

Thanks guys any help is appreciated.

canuckwrx · 07-09-2008, 02:00 AM

Oh yeah also thinking about welding a hi flow cat into the D P or putting the stock one back in.

newtothegame · 07-09-2008, 02:21 AM

Logging the car would be a great start, also pulling the code(s) would help diagnose some also. What gear are you watching your boost and running WOT?

canuckwrx · 07-09-2008, 09:20 AM

4th is giving the symptoms I described. 3rd does it as well but way less often and less dramatic spike and duration in both RPM and boost.

canuckwrx · 07-10-2008, 12:32 AM

K I just went out and hammered on the car a little cause what I thought happened last night just wasn't making sense to me when I thought about it today. I left a light and brought it up to damn near red line in 1 2 and 3 and held it to a little less than red line in fourth. The boost spike was still there but far less than doing a roll on from 2500-3000 in fourth. When I slowed down the CEL started flashing right before I came to a stop. Last night when I said it wasn't picking up speed to match the RPM jump I must've been smokin somethin other than ciggarettes.

03 CrazyTaxi · 07-13-2008, 12:19 AM

Couple questions.

Has it been tuned for catless?

The RPMs rising while the car doesn't seem to accelerate would be a clutch slipping. Does it have an odd smell after that?

If the car wasn't tuned for catless, you'll have a check engine light for that and you'll boost spike like crazy since the turbo can spool up ALOT faster but the car doesn't realize it and panics.

IIRC, if you don't clear a CEL and you get another one it will flash. Also, it will flash when it detects a knock. The idle. . . well could be bad fuel, could be bad plugs, bad coil packs, bad injectors, clogged fuel filter... There's alot of things it could be. Might be as simple as the tune though. Oh and a timing belt is actually alot easier than it looks. Let me know if you want to know how. Probably still have the step by step from when I did mine.