bad eec

[sparkey]

This mabe simple question I have a 88 2.9 I have been working on for a while. I am to the stage where its time to start it long story short the wires on my fuel relay were swisted and had some bare copper touching. This made my eec relay chatter and my fuel pump run as soon as you cut the switch on. I have fixed the bad wires but if 12 volts was fed to the computer will this burn it up or is protected in some way

 

[Earl43P]

Should be OK.

You should get a CEL and the FP should run for 2 sec. when you turn the key to Run, before cranking the starter.

If you've got that, the computer should be fine.

 

[sparkey]

So far it won't I have to use the vip test connector to get the fp relay and eec relay to work so the fuel pump will run, but it wont start the truck that way in my trying to find the problem I started to look at the 22 pin on the ecm. Is this supposed to be a ground? With the battery hooked up, switch on, if I put a test light to this wire it burns the bulb then hook up the vip test connector to the battery ground and the light goes off but if I check it to ground with a meter its about 450 resistance on the meter can't figure out whats up I don't think this is right

 

[kimcrwbr1]

Sounds like computer grounds to me if you have power to all the red wires on the engine with the key on, solenoids, injectors and relays fuel pump relay and eec find all the computer grounds take them apart and sand them metal to metal. The same with battery,engine and chassis grounds. The ground pins on the computer are 40 60 20. 20 is ground to chassis and 40 and 60 go to the battery blk/ltgreen.

 

[kimcrwbr1]

The battery ground also goes to the eec relay blk/ltgreen.

 

[sparkey]

I checked some wires for power with the ecm unpluged and found some wires that had 12 volts 1,2,4,5,17,36,40,56,and 60 this is probably not the way I needed to check for power but should this be I will hook the ecm back up and try it that way also

 

[kimcrwbr1]

With the key off and the computer unplugged check for ground at wire 20, 40, 60 there should be little or no resistance those are the grounds for the computer. Plug the eec computer back in turn the key on and check for power at the relays fuel pump and eec red wires. Did you check/clean the grounds batt to engine, battery to chassis. battery to harness, engine to chassis.

 

[sparkey]

I can get 20 to ring on my meter but not 40 and 60. when I cut the switch on 40 and 60 have 12 volts on them with both fp and ecm relays unpluged is power at these two points nomral with the switch on with ecm unpluged.

 

[sparkey]

I got it to start it was a ground like yall said. There was a single wire connector that had 12 volts on it that I found with my meter when I was looking for my grounds why it had 12 volts on it I though that it went to something that needed power but when I grounded it then rechecked 40 and 60 pins and they was grounded hit the key and voila. Thank yall for helping me with this I hope someday I can help yall with your questions that you may ask
Brian