Thread: Chipped pistons options

Scanmaster? nevermind searched it......**** its more then the scanguage. So is ZZp the cheapest for the scanguage?

Could this be a boost bypass valve issue? I don't even know what pressure they are good for stock? I guess i should be searching the ish eh?

Originally Posted by Bio248

unless the BBV is getting stuck closed then i dont see how that could be causing it. pop the hood and see if the diaphram moves when you goose the throttle.

drive by wire FTL. OK well I goosed it and my boost guage is jumping up, damn near pegging so I got a problem for sure. The diaphragm linkage is all the way up, I can push it down,but can't see if it's moving from in the car. Damnit

Originally Posted by Bio248

phone a friend.

I have no friends....well not around here. OK this is what I see, the actuator moves down when the ignition is turned off, it goes up at startup. If I push it down while idling it starts making some racket. I'd assume it's working? or should I just bypass the solenoid and run it off vaccum once?

ok I'll try that tomorrow, went for another ride and the boost appears to be under control better,but will still verify the actuator operation is correct.

I pinpointed my noise my trans is whining like a *****, especially in 1st. well off to work for me. Thanks for the help bio

well a little update with the GTP if anyone gives a ****.

Trans whine was from fluid, ended up adding a few more quarts to get it at full while running. It's been awhile since I worked on a car that needed to be running to get the proper fluid level...OOPS

Boost appears to be fine as I can drive it around and stay out of boost with no problems. I think it was a freak occurance when it pegged under light load.

I finally got a code and of course I'm back to misfire on cyl #3. The plugs are brand new and the wires are less then a year old. So, I picked up some new coils and reset the computer. About to go on another long drive to see how it responds.

Being that this car has 115K miles on it, coils seemed like a good start. Are there any known ways to test them? My misfire only comes on under moderate load/boost. I can actually do short bursts of acceleration at times with no misfire sensed or felt. I still need to find/order a scanguage to monitor this thing better.

You're right I was thinking that when I changed out the coil packs "maybe I should just swap them first" But, then I said **** it the damn car is a GM and it has 115K miles on it.

I went on a longer drive and the misfire is still there under load. At idle it's smooth, actually pulls decent below 3500rpms, but once you start getting around 3-3500rpms it becomes evident something is amiss. I was thinking injectors also. I'll swap the #3 injector and see what happens with the misfire then.

Originally Posted by Bio248

for some reason it sounds like you have a clogged cat. im not reading back to read your mods or what youve done, but no power and bogging is usually a restriction in the system. is it making excessive boost and knocking?

The problem is it actually pulls pretty good til I hit 3000-3500rpms, then it bogs down, loses power and eventually knocks(which I did twice and said enough of that) The car is bone stock outside of the L67 pistons and ARP rod bolts it is all OEM.

Also are these cars susposed to stop revving at 3500rpms in park? I was slowly revving it up last night in the driveway listening for unloaded noises and noticed it just stops revving.

I still need a real boost gauge and that scan gauge would be great too for troubleshooting purposes. Basically the symptoms are it can't rev past 3500rpms,begins to misfire around 3000rpms under load,will knock if I just keep trying to accelerate, the trans also gets finicky between the 1-2 shift when this is going on.

I guess pulling my cat is the next option.....great

OK good to know.

I was looking at the ZZp off road downpipe. With that I'll need the O2 simulators,but no more cat worries. I'm gonna drop the cat today or tomorrow when time permits. Any suggestions on a downpipe are greatly appreciated.

OK I'll look into the 3" offroad pipe w/O2 sims and appriopate bungs for my 04. I guess I should have just got headers from the get go

Well I finally got the cat pipe dropped and found it full of aluminum Once i saw this I knew what my problem was, so I gutted the bastard. After a thorough gut job I bolted her back up and went for a drive. She breathes once again. No more supercharger flutter, no more misfire, no more revving problems. Amazingly it sounds good too, not much louder then stock which was a pleasant surprise. Now just to take care of the SES light and continue breaking it in.

Thanks again Bio for the help