Greetings,
I am just finishing a top end rebuild of my 87 bii auto 2.9 and Sunday I started it for the first time after 2 years of my project sitting around. I started the rebuild in early June.
Anyway, After I started it the engine runs very roughly, and as I attempt to adjust the timing it seems better but then idles so rough I had to adjust the idle screw nearly all the way in to get a decent idle, at about 1100 rpm's.
I am a novice at setting these things up, and although I have a few manuals I used, none of them report a timing spec. As I replaced the distributor during the rebuild the manuals had me set the timing at tdc, but I doubt that’s correct for normal operations.
Can anyone give me the degree of advance and rpm for this setup?
Also, is there a way I disconnect from the automatic (vacuum) advancing of the distributor?
Are there tools (testers) I can get to help my situation? Without going to the dealer for them to test?
I have learned a lot about this stuff over the past 6 months, and I want to know more. (Like the finesse of tuning this engine, or any engine)
Let me know if you can help, I am anxious after such a long project to see it run smoothly.
Best regards,
Mike

 

10-12 ' and thats with the spout connector out, the spout is just a shorting plug at the end of a wiring harness very close to the distributor.

 

Furthermore, the SPOUT connector Ken mentioned is part of how the computer advances the timing. That's why it's important to adjust the base timing with the SPOUT disconnected: so the computer isn't controlling the timing.
Once you have the base timing set, you can check the computer's ability to advance the timing. This check occurs during the KOER EEC-IV test, in between the engine id code and the dynamic response pulse. During this time, the engine will run at an accelerated RPM with a fixed timing advance of base + 20°.

 

Could you please explain the test methode you describe in your reply? KOER EEC-IV test? Is there a tester I need to view these codes and where do I find the tester (auto-parts, ford, etc..)?
Thanks for the great information.

 

Check out the link in the tech info post on pulling the eec-iv codes, that should explain everything.

 

Thanks for hint about tech info posts.

One more qustion before the weekend and I get some time this weekend to work on the bii,

when i try to set the idle speed, the engine speeds up drastically and then slows down by itself. Any clues as to what causes this???

 

I assume you're attempting to adjust the idle speed by turning the screw at the throttle plate, like you would on a carburetor. If this assumption is correct, read on. If it's not correct, then my suggestions are probably worthless, as usual.

The computer controls the idle speed, not the throttle plate. The proper procedure to adjust the throttle plate stop screw involves reading the voltages from the TPS (throttle position sensor) as you turn the screw. You have to adjust the screw until you get a specific voltage from a certain wire on the TPS. I don't know the specifics offhand, but someone else might.

The computer adjusts the idle speed by changing the position of the IAC (idle air control) on the upper passenger side of the intake manifold. It's basically an electronically-controlled throttle plate bypass valve. There's a faily large vacuum line connecting the IAC to the throttle body.

If I were in your position, I'd probably do the following (keep in mind this is free advice from a mechanical amateur):

1) Make sure the IAC is clean, not sticking, and is properly connected (vacuum line and wiring).

2) Since the throttle plate stop screw has already been messed with, I'd probably just set it so the throttle plate is very nearly completely closed.

3) Check the computer for codes, and let it re-learn the idle speed settings (temporarily, see number 4). This may take a day or so normal driving.

4) Search online or wherever for the proper way to set the thottle plate stop screw. I've read it somewhere before, but I'm not sure where. As soon as you find it, re-adjust the screw using the proper procedure. It may take the idle a day or so to 'normalize' after you do this.

Good luck!

 

The engine will almost stall if you disconect the IAC and thats normal, put the screw back to were it was.

 

Thanks for all the help, this weekend went well for the setup. The timing worked out but I was unable to run the self diagnostics as I believe there may be another problem. My thanks to all.
Mike