Someone who's interested in purchasing my nitrous kit came over today to check it out. While he was over we did a compression test for him. Before he got here, he didn't have a CEL.

We pulled the plugs, did the test, replaced the plugs. He started the car and shortly after he got a CEL. I pulled codes 0201 (ignition) and 0304 (KS).

The strange part is that the CEL doesn't stay on. It flashes randomly when driving. There isn't any pattern to its flashing.

I assumed we didn't connect a coil pack well, but they seem ok. He put the plugs in, and I thought maybe he didn't get them in all the way, but a plug doesn't have to bottom out to ground, does it?

The car drives fine with normal power. Its a 95 auto.

Any ideas?

 

bump

 

 

I'm not sure exactly but I know if you do the ECU thing, it'll enter
a diagnostic mode for the o2 sensors. I think.

 

Huh?

 

Get thee to a Chilton's/Haynes' manual!
I can't really explain it, mostly because I don't really understand it. Does it start blinking @ about 2000rpm?

 

No, It's complete random. I have the manual, I've read/reset an ECU several times before. I've never seen this.

 

I think he's right. I don't totally understand it, but if you do a diagnostic to pull codes and drive the car right after it'll stay in a diagnostic mode. This allows you to test the O2s or something.

In your FSM it talks about the diagnostic modes on page EC-65.
-hype

 

Well, all I did was read the code, and reset the ECU. I followed the same procedure that I have before, and never seen this. How do I get out of it?

 

Did you turn the screw fully counterclockwise again? That FSM page I gave you really explains it all (you do have a FSM right?).

Here's the bold at the bottom of the page
Switching the modes is not possible when the engine is running
When ignition switch is turned off during diagnosis, power to the ECM will drop after approx 10 seconds. The diagnosis will automatically return to Diagnostic Test Mode I
Turn back diagnostic test mode selector to the fully counterclockwise position whenever vehicle is in use

If you need a picture of the page I can send it to you Eric.
-hype