1989 Ford Escort GT 1.9L HO starts then dies after a few seconds. My escort starts rough then smooths out to a good idle then after a few seconds goes back to running rough then dies. It has new plugs, wires, rotor, idle air control motor,fuel pump( I can hear it) , tfi module is good(had parts store test it). When its running for the few seconds there seems to be no smoke of any color coming out the tallpipe. I dont think its the cat-converter cause i took out the o2 sensor to open up an escape area for exhaust if it were clogged but there was no change in the way it ran. Could it be the fuel pressure regulator or the ecu PLEASE HELP Thanks

If the problem is not a vac leak, it could be the idle circuit inside the carb. You may have to replace or rebuild the carb to fix it.

1997 escort idles rough, the first thing is to make sure the throtlebody plate is clean. This sounds like the idle may be staying to low at times if it smooths out with ac on, when the ac is turnned on the computer raises the idle a touch to make up for the strain on the engine from the ac compressor, clean throtlebody and look at and clean idle air control valve, if this valve is not controlling the idle when needed the engine will idle lower than normal and cause a rough idle.
Another thing is the sparkplug wires, take a look at those, if at night or with a good eye use a spray bottle and spray a mist over the wires and watch for any sparking, this spark may be very small so look at each wire closely or may be big enough to see and hear. this is where i would start. good day.

recheck your cam timing belt, sounds like it jumped on you. PCV valves generally plug into the valve cover and you would have had to seen it when you pulled the head. not all cars have them

There is a TSB for the PCV hose. The elbows at both ends get holes in the underside that you can't see unless you remove them and look. This is a very, very common issue on the ZX2. You can get a new PCV hose with both elbows for about $30 from the Ford dealership. You only need to remove the air intake to gain access to the PCV hose to replace it.

If you can find the IAC valve(idle air control) on the throttle body-it should be replaced or try to clean..If you put in new plugs and they turn soot black in a short time period, you have other issues-possible internal engine,such as valve train problems, or a partial exhaust blockage, or the fuel your buying is not good...

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Your Idle air control valve is probably going bad. It is located on the throttle body and is a relatively easy fix as it is only held in with 2 screws. Good luck and thanks for using FixYa!

Check the idle air control valve. This sounds like it is not working right. it controls how much air the engine gets when it is idling. the pcm tells it to open more or close. they get old and dont respond fast enuf.

Good luck

Alternator might be bad take it off and take it to an autoparts store they usally test it for free. Its obviously not getting enough power, check all the ground cables in the engine compartment. If anything try a stronger battery like Duralast Gold.

there is a cut off switch that is located behind the interior trim in the right hand front foot well. just remove the cover trim and reset the switch.