Gents,
After a very trying comedy of errors, it appears we have an internal oil leak remedied on my dad's pristine '90 SC (ends up being a very small crack in a pushrod bore that only showed up after pressurizing the longblock which we should have done long ago). Thanks Dave D. for guidance. Pardon my excitement, but we have countless hours and dollars into a Kroyer's racing machined, nitrous built short block and big valve, ported heads.
Motor is running strong when warm, albeit we think a tad rich given plug evidence. The only remaining obvious poor driveability symptom is a hard start when cold. Please don't fry me as I have been tasking the search function pretty well. Here are some conclusions:
Fuel Pressure - only 14-18 lbs. upon KOEO unless key is trurned on and off several times which then primes it to 40lbs. Replaced the Regulator, no change. However, not likely the source since if I prime it with a few key ons prior to start (again 40lbs.) it still starts hard. Once started and during cranking, pressure is good. I think the pump needs to be replaced but I think this is unrelated to cold hard start condition. No noticeable leakdown.
Cam Sensor - if it was a bad sensor, wouldn't the condition exist whether cold or warm?
Crank sensor - shift light on when in Run, goes off when cranking. BHJ balancer so that's not the issue. Would crank sensor act differently with cold motor (garage is 60 degrees, incidentally and this is Vegas) vs. warm?
Vaccuum leak - can't find one. Been over lines and plumbing numerous times.
02 - relationship to cold?
TPS - checked and .85 closed then 4.5 wide open.
IAC - relationship to cold?
DIS - relationship to cold?
MAF - Cleaned. Relationship to cold?
Sorry for the long note I just wanted to address some of the potential questions up front. Any help to bring at least this phase of the ordeal to a conclusion would be immensely helpful.
Thanks!
Larry
After a very trying comedy of errors, it appears we have an internal oil leak remedied on my dad's pristine '90 SC (ends up being a very small crack in a pushrod bore that only showed up after pressurizing the longblock which we should have done long ago). Thanks Dave D. for guidance. Pardon my excitement, but we have countless hours and dollars into a Kroyer's racing machined, nitrous built short block and big valve, ported heads.
Motor is running strong when warm, albeit we think a tad rich given plug evidence. The only remaining obvious poor driveability symptom is a hard start when cold. Please don't fry me as I have been tasking the search function pretty well. Here are some conclusions:
Fuel Pressure - only 14-18 lbs. upon KOEO unless key is trurned on and off several times which then primes it to 40lbs. Replaced the Regulator, no change. However, not likely the source since if I prime it with a few key ons prior to start (again 40lbs.) it still starts hard. Once started and during cranking, pressure is good. I think the pump needs to be replaced but I think this is unrelated to cold hard start condition. No noticeable leakdown.
Cam Sensor - if it was a bad sensor, wouldn't the condition exist whether cold or warm?
Crank sensor - shift light on when in Run, goes off when cranking. BHJ balancer so that's not the issue. Would crank sensor act differently with cold motor (garage is 60 degrees, incidentally and this is Vegas) vs. warm?
Vaccuum leak - can't find one. Been over lines and plumbing numerous times.
02 - relationship to cold?
TPS - checked and .85 closed then 4.5 wide open.
IAC - relationship to cold?
DIS - relationship to cold?
MAF - Cleaned. Relationship to cold?
Sorry for the long note I just wanted to address some of the potential questions up front. Any help to bring at least this phase of the ordeal to a conclusion would be immensely helpful.
Thanks!
Larry