Alright, so my car has the usual Camaro problems: no power, hesitation, backfire. I was looking through the GM manual at the possible causes of these and for hesitation it mentions HEI ground cct 453. Now according to the diagram for code 42, cct 453 (blk/red) should go to the ECM and then ground.

So I went and tested this wire with the ground off, and I did not get a connection to ground. Then I turned the ignition on and checked it. This time, I still did not get a connection to ground, but it started doing something. Keep in mind that I disconnected the 4 wire plug from the ignition module. While I was checking with the ignition on, a digital multimeter connected between cct 453 and gnd, it started making sounds like a clicking and whirring. I don't know if this is bad or good or what. I drove it afterwards and it seemed fine.

Now, does anyone have any experience with this problem, or have a clue what I'm talking about. There's no real test for it in the GM manual so I'm not sure if the ignition should be on or off. I feel this could potentially solve my problems. The GM manual also mentions that "This wire is grounded in the distributor and makes sure the gnd cct has no voltage drop which could affect performance. If it is open, it may cause poor performance.

Maybe someone could check this wire on there car, tell me what they did and let me know of the results.

Thanks guys!

 

Which manual are you using?

edit: some stupid big pics for everyone

 

Ya that's the chart, but your's is a little different than mine, and that chart doesn't check cct 453. Any advice?

 

may be a difference between the 85 & 86 models.

 

If I find my '86 manual tomorrow (in my room, at least, I hope it's in there), I'll compare your '85 chart against mine. I wouldn't think there was a difference, either... odd.

 

Actually, the chart has all the same information. It's just the layout's a tiny bit different. But if you read the trouble tree, it doesn't actually tell you how to check cct 453. I think I should just take the connector off the ECM and run a wire from the terminal to under the hood, and then use the meter to check to see if the wire is open. Is there anything I need to know about taking the ECM connectors off?

On a side note, I finally went out and bought a digital meter of my own made by Equus (same brand as my tach), and the beeper on the continuity checker doesn't work. It's a pretty good deal for $20, but I'll have to take it back and get a new one.

 

make sure the meter is a 10 mega-ohm range, or you could damage teh ecm when testing.

 

Tis. It's made by Equus who makes gauges, tachs, and other products for cars. This meter is 10 Mohm so that it can be used on cars.

But does anyone have any advice about my problem?

 

No one have any experience with cct 453?

 

Don't know, still can't find my manual. (Panic sets in...)

If you go to http://www.sunpro.com and click on their garage sale link, and then in one of the subsections (Test and Tune, I believe), they're selling a $90 digital meter for $20.

 

Did you check for your manual underneath that valve cover under your bed?

The thing that confuses me, is if you look at the pictures that project posted, the diagram shows cct 453 going to the the ECM and then gnd inside the ECM. But if you look at the electrical schematics in the back of the manual, it shows a somewhat different connection.

 

Did you find your manual yet Tom?