i've had my obd0-obd1 harness with a chipped obd1 ecu for about 3 years now. i always noticed that if anyone touched the ecu with your foot or something the car would hesitate a little. then yesterday it just died on the interstate and when i tried restarting it i noticed the main relay was clicking super fast. i checked all my grounds and they seem to be fine. i pulled the ecu and hooked it up to another obd1 car and it worked fine, so it's def not the ecu. i also noticed that when i moved the ecu around while it was hooked up the clicking would slow down sometimes or stop for a split second.

oh yeah, i also forgot to mention that i installed my old obd0 ecu and the main relay didn't click super fast. it clicked once and primed the pump. then i installed and obd0 distributor and tried cranking the car with the obd0 ecu/distributor. now the main relay clicks normally when i turn the key to ON, then when i try to start it, it starts clicking while the engine turns over. i have no idea what that means?

edit: i took the harness off and tested the pin from A7, it actually splits into 2 wires and runs into 2 pins on the obd0 side. anyway, 0 ohms, seems to have a good connection. i'm pretty sure i'm picking the right pins. the A7 pin is the 4th from the left on the top row right? when you're looking directly at the ECU. so is it possibly not the adapter harness?

 

Sounds like the ECU jumper harness might have some loose contacts in the connectors.
A7 on the OBD1 connector would be the wire I would be checking.

 

ok, i'll go check that now. thanks.

 

ok, i took the harness off and tested the pin from A7, it actually splits into 2 wires and runs into 2 pins on the obd0 side. anyway, 0 ohms, seems to have a good connection. i'm pretty sure i'm picking the right pins. the A7 pin is the 4th from the left on the top row right? when you're looking directly at the ECU.

 

oh yeah, i also forgot to mention that i installed my old obd0 ecu and the main relay didn't click super fast. i'm pretty sure it just did the one click like usual.

i wouldn't have a problem going back to my obd0 ecu, but now i have an obd1 distributor.

is there anyway to use the obd1 distributor with my obd0 ecu?

 

anyone?

 

No. You can't use the distributor for a OBD0 on a OBD1 ECU. On both distributors there is a little rod in there which counts the engine revs. On the OBD1 there are more teeth than on the OBD0 which will result in a fault code or even not may run the engine.

I also think there is a loose connection or maybe a break in the wiring. You mentioned when somebody put his or her feet against it or you mived it conditions changed...?
Search for the problem in the re-wiring harness. It also be a faulty ground wire in that harness.

 

i tested all the connections on the conversion harness. seems fine. also i put a obd0 distributor in the car and my old obd0 ecu. the main relay clicks once like normal, but when i try to start the car, it clicks every time the engine turns over. i'm stumped.

 

I only had the same clicking from the main relay when cranking the engine. This was when the battery was low. I'm not saying this is the case with your problem, but it got me thinking....

I've looked through the workshop manual because I'm also dazzled and can't rest until the problem is solved.
The main relay is powered by the ignition for the first relay to open and give power via the battery to the ECU (A13 & A15). This then gives power to the same connection (although internal) as the starter switch which then powers the fuelpump. However a coil always needs power to engage the switch side of a relay. Positive and negative. Now this is where it gets interesting...
The first of the two relays gets its negative power from a "normal" ground source. The second one gets its negative power from the ECU (A12 & A14). Maybe there is a problem there.

An other possibility might be your ignition switch... Just for say, what if there is a faulty connection in the switch for the starter signal or maybe the ignition signal.
I've had it once, the latter, and the engine just died on me driving through a corner.... By rocking the key in the ignition position it got back power. Had to restart the engine though.

So now there are a few things you can check out. I would try to check out ECU pins A13 & A15, but also A12 & A14. If you're going to check the wiring from the ignition switch please take note, these go through the dash fuse box.... Maybe a bad connection in here?

If you need any help on how to go on some of these things or need help getting a link to a workshop manual just let me know

 

I am running into a similar ecu grounding issue. minus the clicky main relay. I am able to get the main relay to prime the fuel pump, but I get silid check engine light and no spark from dizzy. I already ruled out engine ground and a problematic ecu.