Well, we stumped our dealerships. Back to the truck..98 Chevy 2500
This we know:
-Its a 350
-Its an electronically advanced Distributor
-LS1m Scan Tool reads data accurately.
-No Compression Leaks, all new sensors, complete test down.
-We have to advance the timing to start the truck, 8 degrees
This we are unsure of:
-The Cam Position (stock)
Haynes states 6 o'clock along with Chilton’s, All data states 12 o'clock. When we ran it at 12, it wouldn’t even start, it was firing on the intake stroke. We are at 6 which is at complete TDC, a kit was used to verify. It will start and run very LEAN with misfires. (Advanced Timing)
-The effects of the cam
The cam is not an extreme lift or duration cam
In open loop the truck starts up, no code is set until the car has warmed up, and it cycles to closed.
First off, Is it normal for cammed engines to advance timing during cranking (Centrifugal Advance Distributors did’nt advance until the engine was started?)
Second, Is this Ignition System HEI? If anyone could enlighten me on technical names, that would aid our search.
As far as DTCs, We are getting a Crank / Camshaft Position Code. Is there a CASE learn procedure for this?
I’m taking a shot in the dark, but would the duration change from the cam cause this code?
If so, would delaying the current or voltage impulse by a static time be a possible fix, accompanied by a MAF mod to compensate for any A/F conditions?
[ 21. January 2004, 08:12 PM: Message edited by: bavarian built hot rod ]