'89 22RE Ignition Timing

I just installed new filters, rotor, dist cap, and plugs. Then I tried
setting the timing as per the VECI tag on the hood. It calls for shorting
Test and EC1 ports on the diagnostics connector (a test connector) and 5 deg
BTDC at 850RPM. Before I did anything, I checked it and it was around 14
deg. I set it at 5 deg but the engine has no power then. The test
connector doesn't seem to have any effect at all. Setting the timing back
to 14 deg at idle, I rev the engine while watching the timing mark, and it
drops almost to 0 before picking back up and advancing beyond 14 deg. This
seems strange, is it normal? Is there a vacuum hose that needs to to
plugged to set timing or how do I do it? The damn Haynes book I have is
useless.
Thanks,
chuck

If you short test and E 1 and the timing doesn't change it is
often because the TPS is set incorrectly. It has to tell the computer
it is at idle before it will set timing back to base idle. so loosen
screws on TPS (throttle position sensor till it shows probable 0.5
volts or so, or just turn it a little in the right direction and
tighten it then short connector and see if timing changes (you can
usually hear the difference in engine speed.

"edmechanic" <edokamoto@earthlink.net> wrote in message
news:1109708878.182691.138930@f14g2000cwb.googlegr oups.com...
> If you short test and E 1 and the timing doesn't change it is
> often because the TPS is set incorrectly. It has to tell the computer
> it is at idle before it will set timing back to base idle. so loosen
> screws on TPS (throttle position sensor till it shows probable 0.5
> volts or so, or just turn it a little in the right direction and
> tighten it then short connector and see if timing changes (you can
> usually hear the difference in engine speed.
>
Thanks edmechanic,
I get about 1 volt VTA to GND so it is too high. Also the IDL contact
may not be closing. With the voltmeter between IDL and GND I get over 5
volts. When I do this it definitely retards the engine and the timing was
a few degrees ATDC. I need to find a special offset philips to loosen the
lower screw on the TPS.

"cjensen" <1@2.3> wrote in message news:d04n0e023bv@enews3.newsguy.com...
> "edmechanic" <edokamoto@earthlink.net> wrote in message
> news:1109708878.182691.138930@f14g2000cwb.googlegr oups.com...
> > If you short test and E 1 and the timing doesn't change it is
> > often because the TPS is set incorrectly. It has to tell the computer
> > it is at idle before it will set timing back to base idle. so loosen
> > screws on TPS (throttle position sensor till it shows probable 0.5
> > volts or so, or just turn it a little in the right direction and
> > tighten it then short connector and see if timing changes (you can
> > usually hear the difference in engine speed.
> >
> Thanks edmechanic,
> I get about 1 volt VTA to GND so it is too high. Also the IDL contact
> may not be closing. With the voltmeter between IDL and GND I get over 5
> volts. When I do this it definitely retards the engine and the timing
was
> a few degrees ATDC. I need to find a special offset philips to loosen the
> lower screw on the TPS.
>
Update.. I remember having fiddled with the throttle plate adjusting screw
to set idle a long time ago. I left the TPS alone and turned this adusting
screw back until the IDL to GND contact closed. This retarded the timing
and RPM. I reset RPM with the correct idle adjustment screw. Shorting Test
and E1 brought the ignition to base timing as expected and I was able to set
the 5 deg BTDC as required. Runs great now. Thanks again edmechanic, you
pointed me in the right direction.

You know how I found out this little bit of information. Well I
have a 89 Toy truck, 2.4L and couldn't set it because I was doing a pre
smog tune up. I worked part time at a part time auto shop. So I
figured my distributor was off so I played around with that. That
didn't work so I spent 150 for a timing gear set and changed the chain.
Well that didn't help and I finally read about the TPS on a web site.
Boy I felt stupid, but I learned about that and it works for all old
toyotas, so pass it along before they waste 2 days changing the chain.