New ECU, car won't start (Page 1/2)
SecretMoparGuy OCT 12, 04:39 PM
I had some electrical issues on my 86 auto V6 car. It would run at 800 rpm for 2 seconds. Then it jumped to 2000 rpm, CEL, and die. It threw code 12 22 33 45? Basically TPS, MAP, and Rich running. I spoke to previous owner (a flipper who didn't have the car long.) Said he replaced new TPS and good MAP and ECU. I replaced the O2 as the old one broke off. He said the same thing happened so he took the ECU back and got new one warranty. I got the new reman ecu. Now the car will not run. I did disconnect battery before I replaced new ecu. It has spark. I can hear fuel pump. It will run for 1 sec then die. No codes. Not even 12. Any thoughts?
Gall757 OCT 12, 06:12 PM
Is the check engine light on when you turn the key? You should be able to see code 12 if the ECM is working, so it is not working.
olejoedad OCT 13, 08:49 AM
Check ECM fuse in fuse box.
SecretMoparGuy OCT 13, 09:32 AM

quote
Originally posted by olejoedad:

Check ECM fuse in fuse box.



The fuses under the dash are all good.
SecretMoparGuy OCT 13, 09:34 AM

quote
Originally posted by Gall757:

Is the check engine light on when you turn the key? You should be able to see code 12 if the ECM is working, so it is not working.



Yeah no CEL at all. I am getting a used but supposedly good ECU off a guy I bought some other parts from today. I'll let you know how that goes.
Blacktree OCT 13, 09:43 AM
I would suggest checking the engine grounds. The sensors ground to the engine block, by the bellhousing (firewall side). Look for broken wires, or eyelets hanging loose. Also check the ground strap. It attaches to the firewall side cylinder head (near the battery), and goes to the chassis.
Gall757 OCT 13, 10:53 AM
Is the Connector tight?
SecretMoparGuy OCT 13, 01:20 PM

quote
Originally posted by SecretMoparGuy:


Yeah no CEL at all. I am getting a used but supposedly good ECU off a guy I bought some other parts from today. I'll let you know how that goes.



Used ECU has CEL and starts car. So new reman ecu was not working. Still has the problems but throw only code 33.

There are two broken ground wires I think I will upload pictures.
SecretMoparGuy OCT 13, 01:37 PM

quote
Originally posted by SecretMoparGuy:


Used ECU has CEL and starts car. So new reman ecu was not working. Still has the problems but throw only code 33.

There are two broken ground wires I think I will upload pictures.



Here are the pictures of the two broken ground wires. The first is on the right side of the car near the trans. The second is on the left behind battery. Does anyone know what these go to?

https://imgur.com/a/VudHFUR

[This message has been edited by SecretMoparGuy (edited 10-13-2019).]

olejoedad OCT 13, 04:13 PM
The ground wire by the battery provides grounding from the terminal to the space frame.
The ground wire by the transmission connects to the drivetrain and the lower frame rail on the driver side of the car.
Both are crucial to proper operation.
Repair them.
While you are at it, there.is a ground strap from the front head to the passenger side hingebox stud.
Clean both attachment points.
Clean the ground wires from the engine harness to the transmission to engine bolts, and also the ground wire from the harness to the driver side hinge box.

You car will like you for the effort.