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Old 11-15-2017, 12:23 AM   #26
chris989
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Join Date: Dec 2011
Location: Boise, Idaho
Posts: 361
Re: How do I kill this automatic function?

Quote:
Originally Posted by DieselSJ View Post
Got my cable yesterday. It came with a CD that had more than a dozen different scanning/logging programs. I loaded up winaldl and went for a quick drive.

- I have CEL flags that weren't registering when I grounded the pins on the connector and read the flashes. The only code that showed up was for EGR. I also have codes for TPS low voltage and ESC.

- My knock counts are out of control. I'm seeing counts of several hundred on each cycle. Actually it cycles between just a few counts and several hundred.

- Confirmed that my temp sensor is reading correctly.

- IAC operation seemed fine

- I am slightly lean everywhere. This was expected due to the high-flow cat and 3" exhaust that I added. It seems to be within the parameters that the computer can handle though.

Hooked up the timing light and found that my initial timing (with plug disconnected) is sitting at about 10 degrees and is bouncing around. Didn't have time to adjust it. While I wouldn't think 6 degrees of extra timing would really hurt on a sub 8:1 compression engine, the combustion chamber might just suck enough to detonate anyway. Need to investigate further to determine if timing scatter is due to bad/failing ESC or timing chain.

you might be lean because of the advanced timing. I think it calls for TDC with the wire disconnected. I think the computer advances it up to 42 degrees at light cruise?? I will have to open a bin file to double check.

a few hundred knock counts is nothing to worry about. it is normalish. just starting the engine will cause some.

What motor do you have? My TBI is stock at 9.4-1
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Old 11-15-2017, 12:16 PM   #27
DieselSJ
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Join Date: Jun 2016
Location: Phoenix, AZ
Posts: 256
Re: How do I kill this automatic function?

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Originally Posted by chris989 View Post
you might be lean because of the advanced timing. I think it calls for TDC with the wire disconnected. I think the computer advances it up to 42 degrees at light cruise?? I will have to open a bin file to double check.

a few hundred knock counts is nothing to worry about. it is normalish. just starting the engine will cause some.

What motor do you have? My TBI is stock at 9.4-1
Engine is a 87 TBI 7.4.

Doing more investigating and this engine does not have a knock sensor or the ESC circuit. So I think the knock counts are a BS number since this system has no way to sense for a knock. Looking at the logs it appears that the number just increments from 1 to 255 then resets.

It looks like part of my problem may be a bad ignition module which is causing the Code 42. Ran through the diagnostic chart last night and ended with the result of bad module, so I have a new Delco unit ordered.
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