I just noticed another tan/lined single wire with connector on the passenger side firewall next to the blower motor...

I set my timing last month and disconnected a different tan/lined wire on the driver's side right next to the ESCM.. Figure that was it, no question. However I've never been sure becuase this connection seems to control power to the TACH... Here's some pics, hopefully someon can quickly identify the ESC connector for me.

 

Passenger side connector...

 

the passenger side connector in the second picture is the est bypass wire.

 

The first connector is what is referred to as the "tach filter". I honestly can't remember at the moment what it does, but that's it.

And, mystikkal_69 is right, the second pic is of the EST-bypass wire.

 

Ya, just to add, it's the EST bypass connector you unplug to set basetiming, not the tach wire.

 

Roger that, thanks guys. I broke my IAC plug by accident, so it'll be a few days until I'm able to time this thing anyhow.

Oh, before I forget... I have been having some very bizarre problems with this engine over the last couple of months... I noticed with the EST bypass unplugged, or plugged in the engine runs exactly the same. Should it? I think I may have a faulty computer or ESCM, but I'll wait for the IAC plug before I start tinkering on an engine that can't idle

Any links to write ups on full tune-ups to return engines to stock settings would be greatly appreciated.

 

You're on your way by fixni the broken things first..IAC shouldn;t cause an issue with timing. ESC I though was there to retard timing when knock was detected, but been awhile since I diaged it.

Could be you have a broken wire/poor connection somehere? I/e you may be unpluggig the EST bypass which isn't going to where it's supposed to be going. Should be a noticable diffece, IIRC, unplugged you do not have any advance at all.

 

Thanks for the ears and help, Mike.

I don't know what the IIRC is, maybe you could clarify that for me. The EST bypass does indeed do something, because when it's unplugged my SES light is on, when it's reconnected, the light goes out.

ESC = Electronic Spark Control right? From my understanding it does detect knocks and the ESCM is supposed to make the correction for it, however I find myself getting a lot of false information about this stuff

With EST disconnected, do I get no advance, or are you talking baout this IIRC, which I dont' know about.

 

Sorry, IIRC = If I Recall Correctly.

Yes, ESC (as I understand and have troubleshot in the past) is only there to detct information frmo the knocksensor and retard accordingly. I suppose it's possiblle to inhibit tining advance, but am unsure. ON pre-90 the ESC is a seperate modlue by the brake booster, on 90-90-2's t's incorporated to the chip (IIRC) in the ECM.

With the EST bypass connector disconected, you should see little or no advance. I don't recall if there is any "built-in" advance or not, if there is, there would only be a few degrees at most.

 

Dang, I have to proofread better next time