cptrdbrd

I am trying to retrieve the codes from the check engine light as I have done a couple of times in the past. With the jumper in, I should get a code on the check engie light but now the light just comes on and does not blink. I am jumpering the single plug to the one on the one on the top right while holding the plug so the row of 4 plugs is on bottom and the row of 2 are on top.

The reason for checking is the truck will not start and the fuel pump runs and does not shut off with the key on and engien off.I have plenty of fuel at the rail (I did not check PSI but when I press the shrater fitting it squirts 1 good 12" into the air).I also had spark out of the coil and the cap and roter are in good shape.

Recently,it has ben giving me problums like: not wanting to start at first but after I let the pump run for a few seconds it will start, when it starts some times it runs very poorly for about the first 10 miles then it picks up. One time I opend the hood when it was running porly and the fuel pump realy was chattering.

I am thinking the ECM was on its last leg and has died, because the check engine light just sets there lit up and will not give out any codes with the jumper instaled.

Any help would be appreciated.

klricks

Please state model year and engine size. (Add to your profile and/or make a signature).

I have a web page showing how to connect the jumper. See link in my sig.

rikard

Its showing the classic signs of an ECM gone bad. Most of the time its the capacitors that leak causing the board to short out. The computer is located in the drivers side kick panel. The electrical connector is under the hood and the ECM comes out into the engine compartment. The wheel well is in the way but after removing a couple of screws it can be bent (its plastic) so the ECM can come out.
The computer will have calibration numbers which will be needed to get a replacement.
As stated above there are several sites, Steve83s Supermotor site is one, that have lots of useful info for testing and repairing the ECMs
Check the socket for the relays in the box under the hood as they have been known to fail.
regards
rikard

cptrdbrd

thanks for all the great info.
I wish I had the link from Klricks 2 days ago, it would have saved me some time.
It is a 1990 F-150 with a 5.0 or in real life a 302.
I kinda was thinking ECM. I pulled it out but it looks no sighns on the board tht means nothing. befor replacing the ecm I will check the plugs.
How do I find the sight for Steve 83s supermotor sight? I looked for a link in the group and googled it.
thanks to bolth of you.
Paul