Ok I have issues.... Well that is I'm still having starting issues with my 3gm30F. Its hard starting, hot or cold. Acts exactly the same. I have to have the throttle at about 30% to get it started. One cylinder catches right away, the other two lag behind many seconds 5-10 seconds. Once the other two cylinders fire, life is good. This with 60 ish degree F days.
No smoke at startup, hot or cold. Once started and running on all cylinders it runs fine. It has what I think is high crankcase pressure. But it runs at speed fine (once warmed up) in gear
up to 3500 RPM
Turn it off and wait 15 seconds or a minute and its hard starting again, with the same delay firing on 2 cylinders....
I have checked the valves (good), replaced the racor
filter and cleaned the air filter.
are fine, no leaks
, no water
etc. Oil pressure is perfect and it does not run hot at all.
I'm thinking it might be either sticking/back leaking injectors (IE not sealing tight) or the lift
pump is failing. It sort of sounds like leaky injectors. It acts like its not getting fuel
to the two cylinders right away. Throttle response is fine once they are firing. No major smoking at startup, which to me means the fuel
is not getting to the cylinders on two cylinders.
If it was low compression
, I would think I would expect lots of smoke once the cylinders started firing. But no smoke on startup
About 1000 hours on the engine
I'm thinking of pulling the discharge line of the lift
pump off tomorrow and seeing if it pumps.
While it could be low compression
, I would think it would be easier to start once it was warmed up. But it acts exactly the same hot or cold. This has only been a problem since this winter started or sometime after. Maybe in the last month or two...
In other forums
it seems others have this same problem / issue with the GM's and this seems normal. But this engine
use to start up fine hot and was only a little cold nature below 50-55 degrees F.