700 RPM 1200 Rpm

[DeMasi1990]

Hey guys, Im having a problem with my 1990 Ta 5.0L 305 T.P.I . The idle is bouncing from 700 to 1200. I watched the tach go up then down up then down..I am also running a service engine soon light that sometimes goes off then comes back on again??...I have a new fuel presure regulator, heads were just re done, Msd wires and coil and pretty much everything from block up is new, even the EGR...I broke the switch/sensor on the passener side Head and Had it replaced, The fans will not turn on at all. Even in diagnostic mode? Can Anyone help me.. Im stuck here :coffee:

[sphinx_57]

Make sure that switch sensor is pluged in all the way, and check to make sure no wires are sitting on the exaust. Also in my 89 it did some funky stuff when the O2 sensors went out.

[kevstoy]

Sounds like there's an air leak somewhere. Either it's sucking in air at the intake or throttle body, or your idle air control needs replacing. Both of those will cause your problem.

[DeMasi1990]

I este for all that... I Bought a scanner today... The computer says I have a BAD ESC Electronic Spark Control Module....Only question is...Where is it for the 1990 TA?... Its not by the brake booster or anywhere in that vicinity...???

[five7kid]

It's in the distributor.

Make sure the tan ESC wire is making good contact. Being disconnected will set that code.

[DeMasi1990]

Its not that module in the Distributor, That was Changed long ago.. The Other modual is what I was refering to, and In the Book its listed as a EST or EST " ELECTRONIC SPARK TIMING" Modual.. That is what is setting the code.. that modual that sits by the brake booster also by the relays with a terminal that plugs in that look very similar to the cruise control plug...it was setting the code because it wasnt there, the modual itself was GONE, along with the Pigtail...:dontknow:

[FstnBlk]

not to cut into this guys prob but im havin a prob almost the same ecm gives the code 22 something about tps

[five7kid]

Well, you've got a completely different problem. Code 22 is TPS low voltage - Throttle Position Sensor. Typically means the TPS is bad, but could also mean the 5 volts going to it is bad.

[94 Z28 w/issues]

not to cut into this guys prob but im havin a prob almost the same ecm gives the code 22 something about tps

u have a bad TPS

[94 Z28 w/issues]

Its not that module in the Distributor, That was Changed long ago.. The Other modual is what I was refering to, and In the Book its listed as a EST or EST " ELECTRONIC SPARK TIMING" Modual.. That is what is setting the code.. that modual that sits by the brake booster also by the relays with a terminal that plugs in that look very similar to the cruise control plug...it was setting the code because it wasnt there, the modual itself was GONE, along with the Pigtail...:dontknow:

try contacting these guys http://www.fbodymotorsports.com/ call them up they might be able to give you the part with the pigtail