stickybones
What?
- Joined
- Dec 27, 2001
- Messages
- 1,069
Well I'm trying to chase down a knock problem I'm having. When I romp the throttle from a roll, I get high knock numbers on my Scanmaster. Real high...like 30 degrees. My hearing is too poor to hear knock/ping so I can only go by what the gage is telling me.
I drained the tank and added 111 octane. I've raced with this stuff on a race chip and 23lbs of boost so I know it's pretty good.
Anyway, I left my street chip in and turned the boost down to 15lbs. This should be more than enough octane to handle this.
Hooked up TurboLink and went for a spin. Still got some high knock numbers when I romped it.
Looked at the TLink data when I had knock and the MALF light was on in some cases. Codes were for MAT sensor shorted, EGR diagnostics, MAF sensor high, cam sensor failure, TPS high, TPS low...all in the same frame. My scanmaster didn't record any of these MALFs.
What gives? I'm trying to convince myself I really don't have a real knock problem but rather something electrical is SNAFU.
I had another TLink run with MALFs of MAT sensor shorted, EGR diagnostics, MAF sensor high, MAF sensor low, MAT circuit open, open or grounded VSS all in the same frame as well with, get this, 46 degrees of knock, -3.1 boost (or vacuum is more like it), 4.2 volts, BLM of 250 and INT of 0, etc.
Any help here on what could be wrong would be appreciated. Is my ECM taking a poop? Is it the TLink signal that is getting disrupted for some reason? What?
Thanks
Mike
I drained the tank and added 111 octane. I've raced with this stuff on a race chip and 23lbs of boost so I know it's pretty good.
Anyway, I left my street chip in and turned the boost down to 15lbs. This should be more than enough octane to handle this.
Hooked up TurboLink and went for a spin. Still got some high knock numbers when I romped it.
Looked at the TLink data when I had knock and the MALF light was on in some cases. Codes were for MAT sensor shorted, EGR diagnostics, MAF sensor high, cam sensor failure, TPS high, TPS low...all in the same frame. My scanmaster didn't record any of these MALFs.
What gives? I'm trying to convince myself I really don't have a real knock problem but rather something electrical is SNAFU.
I had another TLink run with MALFs of MAT sensor shorted, EGR diagnostics, MAF sensor high, MAF sensor low, MAT circuit open, open or grounded VSS all in the same frame as well with, get this, 46 degrees of knock, -3.1 boost (or vacuum is more like it), 4.2 volts, BLM of 250 and INT of 0, etc.
Any help here on what could be wrong would be appreciated. Is my ECM taking a poop? Is it the TLink signal that is getting disrupted for some reason? What?
Thanks
Mike
