aviatorx Posted September 6, 2002 Share Posted September 6, 2002 This is not Z related, but if anyone can solve my problem I'd be most grateful. The issue is with a '93 Ford 3.0L (no SHO) with idling problems - the rpm's hunt high (~1000 rpm )to low (~ 500rpm)KOEO codes are 111, KOER codes are all non specific 116,129,167,412,521,and 536. The dist cap, rotor, wires are all new (problem existed before they were changed), plugs have been checked and are good. Base timing is correct, but the kicker is that when idling with the SPOUT connector out, the idle settles nicely into base timing, when the SPOUT connector is in the RPM wants to roam. Occasionally the RPM will settle when the vehicle has been driven for a while and is well warmed. The EGR and IAC have been removed and cleaned of carbon, and the IAC has bee checked for shorting (without a breakout box I can't do much more than check resistances, shorts, and proper voltage supply). The TPS has been checked and seems OK as well - I'm stumped. The vehicle seems to be OK otherwise - no hesitation and acceleration is good ... Today I'm looking for vacuum leaks.... Any clues? Quote Link to comment Share on other sites More sharing options...
randy 77zt Posted September 16, 2002 Share Posted September 16, 2002 change the thermostat.the ford thermostat opens at a lower temp as it ages.it is a 192 degree unit.it is going to be winter soon anyway so you might as well set it up now.you will get better fuel mileage with new thermostat.also use dvom on intake air temp sensor but i forget the specs.if it reads open circuit you know its junk.clean the throttle body.some time i cure smog test failures by changing thermostat.if you have a good scanner you can read your data(water temps,intake air temps) as you drive. Quote Link to comment Share on other sites More sharing options...
Guest QIK 71Z Posted September 17, 2002 Share Posted September 17, 2002 You didn't state how many miles are on the engine, if it has high mileage I would check for excess slack in the timing chain. That would cause a timing variation especially with the SPOUT connector plugged in. Also check for TPS voltage to be close to 1.0v @ idle (checked with a DVOM) most scan tools will not give you a datastream with Ford EEC IV. And last, you may just have a faulty IAC valve, most of them respond to cleaning, but some are just worn out and won't work properly no matter how much you clean it, so it may be time for a new one. Hope this helps. Quote Link to comment Share on other sites More sharing options...
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