91 Buick Park Avenue Will not Start
Ok, this is how it started out. It would start after cranking forever, but that was short lived. I can not get it to start at all. It will spit and pop but that is it.
Things i have checked or done.
Replace cam shaft sensor
tested fuel pump pressure(holds good at 42psi)
Test light to injectors ( does go on and off as motor is turning.
Replaced coil pack, (did have one bad cell)
Replaced spark plugs
Replaced IAT sensor
Replaced coolant sensor.
Still will not start. The plugs are wet when i pull them out. I have check for spark and that is good.
So is there any out there have any insight as to the sequence of start up so i can start from the begining and trace this problem down.
I do have the injectors strobing so that means the sync has happened correct.
I did notice that the fuel pressure gauge drops slighty as the motor makes one rotation.
If all injectors were working would a see a small movement of the pressure gauge needle as each injector opened, or could this be and indication of the prime cycle runing evey rotation.
Any usefull help would be apperciated.
Things i have checked or done.
Replace cam shaft sensor
tested fuel pump pressure(holds good at 42psi)
Test light to injectors ( does go on and off as motor is turning.
Replaced coil pack, (did have one bad cell)
Replaced spark plugs
Replaced IAT sensor
Replaced coolant sensor.
Still will not start. The plugs are wet when i pull them out. I have check for spark and that is good.
So is there any out there have any insight as to the sequence of start up so i can start from the begining and trace this problem down.
I do have the injectors strobing so that means the sync has happened correct.
I did notice that the fuel pressure gauge drops slighty as the motor makes one rotation.
If all injectors were working would a see a small movement of the pressure gauge needle as each injector opened, or could this be and indication of the prime cycle runing evey rotation.
Any usefull help would be apperciated.
Senior Member

True Car Nut
Joined: Sep 2006
Posts: 4,816
Likes: 245
From: Windsor, Ontario / Detroit, Michigan









Plugs being wet usually means you are getting fuel but not spark. How did you check for spark? Based on what you checked so far I would look at the ignition control module. Check the connector first.
I have a spark tester that plugs into the spark plug wire and a wire that grounds to the motor. I have had the ICM off. Clean up the surface to the mount making sure it was getting a good ground. the connection was nice and clean. I did not check the yellow,green,blue wire with a tester to see if the ICM was telling the coils to fire. That is a good idea, i will check that tonight when i get home.
Joined: May 2006
Posts: 29,661
Likes: 43
From: Sheboygan Wisconsin






First, 42psi is a bit low. 48 is what you want. I would suggest pulling the plugs and dry or replace. Could be flooded. Listen to each injector to make sure each is pulsing. Even with a weak spark it should start and idle, just not real good. I suspect a fueling problem. You mention the pressure drops after cranking. Fuel pump is what I would be looking at. You can change fuel filter, it'* cheep, and easy, and should be done anyways.
Thanks for your reply. When I am turning over the motor the pressure gauge drops to 42psi and then returns to 45 psi. this happens over and over about the same rate as 1 rotation of the motor. I wonder if that was from all six ejectors opening at the same time. After the sync signal is on all ejectors open at the same time(prime the cyclinders) then the motor is to rotate a couple of times before ejectors start working again. At least this is my understanding of the process.
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