check for spark and the signal from the distrib to the fuel pump
85 Won't Start - Code 12 - Low Oil Presure?
Thread Starter
Instructor
Joined: Jun 2007
Posts: 188
Likes: 0
From: Hatboro PA
85 Won't Start - Code 12 - Low Oil Presure?
Alright, so I've been fighting with this for a few weeks and now asking for help. My 85 won't start. Had it running perfectly in January, didn't have time til 3 weeks ago to try to get it going again. The only thing odd I see on the cluster is my oil pressure is real low, 6 at max, usually around 4 while trying to crank it. The paperclip trick is showing 12, no codes. So, now I'm stumped. Battery is newer, bought it last spring. Help?
Race Director
Joined: Jun 1999
Posts: 14,924
Likes: 9
From: Merritt Ils Fl
Low oil pressure will not keep an engine from starting. Code 12 tells you the ECM is powered and passed self checks. Can you hear the fuel pump run when the key is turned to "Run"?? Have you checked for spark?
Pro
Joined: Mar 1999
Posts: 678
Likes: 0
From: Oslo, Norway
Hi. Check the fuel pressure.
When you turn the key for ignition before starting the fuel pump activates for a couple of seconds. Then stops. WThis is to ensure the pressure is ok. Measure this pressure.It shall be between 36 and 39psi if I am correct.
When cranking there is a fuel pump switch enabled by the oil pressure. Thisfuel pump switch is placed behind the distributor under the fire wall.
It may be the fuel pump relay that is bad to. If I remember coorectly it is placed together with the overdrive relay mid on the firwall on the driver side.
Read in the manual how these fuel relay and oil switch and also the rpm sensor sequence is. There can be hidden the solution there.
When you turn the key for ignition before starting the fuel pump activates for a couple of seconds. Then stops. WThis is to ensure the pressure is ok. Measure this pressure.It shall be between 36 and 39psi if I am correct.
When cranking there is a fuel pump switch enabled by the oil pressure. Thisfuel pump switch is placed behind the distributor under the fire wall.
It may be the fuel pump relay that is bad to. If I remember coorectly it is placed together with the overdrive relay mid on the firwall on the driver side.
Read in the manual how these fuel relay and oil switch and also the rpm sensor sequence is. There can be hidden the solution there.
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