turbov6joe
Signal 1 J-12
- Joined
- May 22, 2002
- Messages
- 2,220
Ok, I'll try to explain this oddity without sounding too confusing. On some occasions at WOT, my boost runs to a set 24-25 psi in 1st and 2nd, then, when it hits 3rd gear, it drops off to 19-20 psi then slowly works it way back up to 24-25 psi and stays there into 4th, and as long as I have the road/balls to hold it. Now, it does not do it all of the time, just randomly, and only from a dead stop. It doesn't matter if the TC is locked or not, and only seems to do it when the boost is set above 20 psi or so. If I punch it from say 55 mph and it downshifts to 3rd, then up shifts to 4th, this problem never rears its ugle head! Now here is the odd part of this all. When it is acting up and dropping to 19-20 psi, the turbo almost sounds like it's struggling/laboring to work its way back up to 24-25 psi (very hard to describe here)??? I can hear a rather loud sucking/vacume sound when its on the rise after it drops off. The turbo is new (about 50 miles), and did it before the rebuild, so that's out for now. The only other thing I did was change the squirters out for a set of 50's from stockers. The state of tune is good, so I doubt the 50's are causing it. I do not remember this problem before the injector upgrade, but that's not saying much, as my memory pretty much sucks most of the time (so my wife says). I cannot seem to put my finger on this one, so bang away with ideas....all will be greatly appreciated!
PS>>I'm using a known good bleeder valve in conjunction with the OE wastegate solenoid.
PS>>I'm using a known good bleeder valve in conjunction with the OE wastegate solenoid.
I did notice that the WOT boost level was down a pound or two at the most, and that the O2's were back up in the lower .8xx range opposed to the mid .7xx's where they were when all of this was going on. Is is possible that the slight KR I was seeing in 3rd gear would have been causing the timing to be lowered enough to cause the boost to drop as it did??? Then when the ECM didn't see any KR, it put the timing back in and the boost came back up??? Maybe, just maybe, when I'm on a roll and nail it, the load isn't enough to cause enough KR to force the ECM to pull out a significant amount of timing, thus causing the crazy boost flux I'm seeing??? Then, when I launch off idle and go through the gears, the load was enough at 24-25 psi to cause the KR and the timing to be pulled out??? Seems that the car felt as though it pulled harder at 22-23 psi then when at 24-25 psi. Maybe that slightly higher boost was just enough to cause just enough timing to get pulled out causing the boost to surge as it did??? I hate to make this so long, but I seem to trouble shoot better when I'm typing/thinking it through. Any other ideas out there?
As for exhaust leaks, my O2's seem too good for that, as well as I don't hear anything that would make me suspect of a leak (not saying it couldn't be a remote possibility). I will R&R the gator clip with something else, as well as R&R the flapper and see what happens. Thanks so much for the insight, as both of these opinions very well could be my problem(s). Thanks!
