ecm and fuel pressure problems- help
Thread Starter
7th Gear
Joined: Dec 2002
Posts: 7
Likes: 0
From: austin tx
ecm and fuel pressure problems- help
help, my fuel pressure stays at 20 - 30 psi and car will not run unless i disconnect maf sensor, also i can not get any codes from my ecm, with key on check engine lite is on but when i ground diagnostic test terminal a and b i get overdrive lite on(od does not work currently) is my ecm bad, or memcal bad. has new fuel pump and pulsator
[Modified by vettered85, 7:44 AM 12/7/2002]
[Modified by vettered85, 7:44 AM 12/7/2002]
Burning Brakes
Joined: Mar 1999
Posts: 858
Likes: 5
From: Fl,USA
Re: ecm and fuel pressure problems- help (vettered85)
When you say the fuel pressure stays at 20-30 psi do you mean when the car is running? Or just when you try to start it? The pump will only run for a few seconds and shut off if the engine doesn't start. Is that with the vacuum line disconnected from the regulator?
20 -30 at idle is low if vacuum line is disconnected.
I need more info to help you but I will say that both items that you mention, MAF & the ECM are notorious for failure. They could both be bad. The MAF could have went and very easily taken the ECM with it.
John
20 -30 at idle is low if vacuum line is disconnected.
I need more info to help you but I will say that both items that you mention, MAF & the ECM are notorious for failure. They could both be bad. The MAF could have went and very easily taken the ECM with it.
John
help, my fuel pressure stays at 20 - 30 psi and car will not run unless i disconnect maf sensor, also i can not get any codes from my ecm, with key on check engine lite is on but when i ground diagnostic test terminal a and b i get overdrive lite on(od does not work currently) is my ecm bad, or memcal bad. has new fuel pump and pulsator
[Modified by vettered85, 7:44 AM 12/7/2002]
[Modified by vettered85, 7:44 AM 12/7/2002]
Safety Car
Joined: Feb 2002
Posts: 4,212
Likes: 10
From: Sun City West Az
Re: ecm and fuel pressure problems- help (vettered85)
As far as the fuel pressure goes, have you changed the fuel filter? If so, you probably need a new pump if the fp remains @ 30 psi while running. It goes without saying that you checked for restrictions , kinks etc. in the fuel lines causing the reduced pressure.
Thread Starter
7th Gear
Joined: Dec 2002
Posts: 7
Likes: 0
From: austin tx
Re: ecm and fuel pressure problems- help (ittlfly)
thanks for replying guys, psi is at 20 - 30 when running and only will run if maf sensor is disconnected, if i connect it back up it will not start, how do you check for bad fuel pressure regulator or bad ecm, i appreciate anyone taking time to reply
Safety Car
Joined: Feb 2002
Posts: 4,212
Likes: 10
From: Sun City West Az
Re: ecm and fuel pressure problems- help (vettered85)
If your pressure is @ 20-30 psi steady; your fuel filter is not clogged; your lines are clear of obstructions then you need to pinch off the fuel return line to the tank. You can do this at the top of the gas tank by removing the gas lid door and removing the rubber bladder. key on, engine off, use a rag to protect the fuel return line and pinch it off with vice grips at the top of the tank. While you do this have some one watching the FP guage so the pressure does not exceed 60 psi. If pressure spikes above 47psi., replace regulator....if pressure is less than 41 psi, then you have a bad pump,pulse dampener disconnected, FP sock restricted or incorrect fuel pump. Good luck
