Ford escort 2l engine surges, changes rpm at idle.

SOURCE: 1987 F 150 Problem: engine idle stalling and then surges

I had the same symptoms on my 1993 F-150. A friend of mine commented that he could smell gas in the exhaust. Eventually, it got to where it would start, then die after a few minutes and wouldn't restart after that (at least for several hours). It turned out to be a bad fuel pressure regulator that was causing it to flood. It was about a $25 part and an hour labor to replace (not difficult, just awkward getting to the hex head bolts).

SOURCE: low rpm's in idle when heating/cooling system is on & surges.

Check your EGR or your Idle control Valve. This can cause a problem with your irratic idling

SOURCE: My 1993 Escort with 1.9L engine surges at idle

Change EGR valve and EFPV(or evp) sensor. Both control idle.

SOURCE: engine idle speed

Sounds like you idle air control valve is starting to mess up. You can actually take this off and clean it with throttle body cleaner and it should help get your idle back to normal. As is sounds the idle air control valve controls how fast/slow your car idles. It is located on the throttle body normally held on with a couple of screws. The throttle body is where the air duct hose coming from the air filter box ends at the engine block. Here is a picture of what you are looking for:
Make sure that you clean the valve portion and not the electrical plug with the throttle body cleaner. Let it air dry or blow lightly with compressed air before putting it back on. Let me know if you have any more questions. Thanks for using FixYa!

Marvin

• 85242 Answers
• Posted on Sep 08, 2009

SOURCE: The engine boggs down at high rpm. For instance,

if the fuel filter hasn't been changed do so, if the fuel filter is ok and has been changed out due to this problem you will need to monitor the fuel pressure under a load and make sure it doesn't drop below 45 PSI, it it does you will need to replace the fuel pump and the fuel filter. U also do say if you have a check engine light or have had the system tested for trouble codes that may be triggered by this loss of power problem.