cold start alternitive
Melting Slicks
Joined: Feb 2006
Posts: 2,753
Likes: 15
From: backwoods upstate ny
He is getting 0 fuel press on key up. He is only getting fuel press when it cranks and builds oil pressure. This is a sign the relay IS bad. I have had the same problem on MANY GM cars. With the key on and not running the pump should run for a few seconds to prime the system so it will start within a few cranks. If he has a leakdown that is a complete different problem unless the leakdown is enough so it will not even build press. If this were the case the car would never run.
Melting Slicks
Joined: Dec 2006
Posts: 3,374
Likes: 86
From: Corbin KY
The reason it starts easy when warm is because the motor has already been running and there is press in the fuel rail (another reason I believe he does not have a bleed off problem) allowing the car to start faster and not have to wait on oil switch for fuel presure.
Advanced
Joined: May 2003
Posts: 96
Likes: 0
From: Moreno Valley CA
Ignition?
Not too long ago I was having longer than normal cranking to startup. I checked all of the usual thing fuel pressure at ignition on and all the rest discussed in this thread. Then I thought to check the supply voltage to the ignition system during the cranking sequence. I found 9.25 volts. So I started to ohm the circuits for draw. I could not fing anything. Then I decided to pull the battery to check the jumper post fusible links individually. When I pulled the positive battery cable I found it very corroded. I cleaned it, put everything back together and the engine fired right up.
I would advise running this test to see what the voltage is as the power transistor needs about 2 to 3 amperes to switch current to the coil and that is if the ignition control module is factory. If the ignition control module is a high performance model it could be requiring as much as 4 amperes to switch current to the coil.
Gary
I would advise running this test to see what the voltage is as the power transistor needs about 2 to 3 amperes to switch current to the coil and that is if the ignition control module is factory. If the ignition control module is a high performance model it could be requiring as much as 4 amperes to switch current to the coil.
Gary
Thread Starter
Pro
Joined: Feb 2009
Posts: 711
Likes: 3
From: charlottesville Virginia
still taking longer than it should but the problem seems to be slightly better, only 3-5 cranks now to get it to start. have replaced fuel filter, fuel pressure relay, replaced a vac line from the regulator to the intake, tps sensor and cleaned the battery terminals. Over night the pressure will drop to zero The manual says to unplug the ecm so it will pick up the changes made to the spark timing, but I can not figure out how to do this when the car does will not start with the ecm unplugged, am I going about this the wrong way?
