off-list Re: 85(870 ecm) open loop hac code

[Bob Valentine]

At 03:17 PM 12/30/2000 -0800, you wrote:
>I am working on a buds car. Right now I have a 7730 in
>it for diagnosing, but his ecm is the 870:(
>I have t okeep the car in open loop to get some work
>done . For the 7730 I just set the open loop temp
>enable to 225.(he has a 160 tstat and he fan are on at

I think you meant closed-loop enable, right?

>180) so it will stay in open loop and run fine.
>His problem is the o2 sensor. I was told RTV could
>have killed it. Well I have athird O2 in it a heated
>one at that.
>The O2 is in the drivers side primary header tube with
>full exhaust cat and all.

Sure could be silicone poisioning.  Try running a redundant ground from the
shell of the 02 to the block or even better the case of the ECM, this would
rule out a grouding issue which can somtimes emulate a bad 02.   Could also
be RFI or alternator noise screwing with the 02 signal. Been there done that. 

>Its there a addy or I was thinking to set the TPS PE
>enable really low. not shurew if it goes that low 0% 
>What other alternative do I have. beside a 7730
>upgrade for his car right now.

If you've done the work to get a '730 in it, might as well leave it.

-> Bob Valentine
-> bob at tecmark.com

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