I have a 1991 Ford Explorer – automatic transmission, 6 cylinder engine, in mint condition with only 90,000 kilometers (60,000 miles). It has been in the family since it was purchased. I have owned it for 2 ½ years. About a year ago the vehicle started choking out when I would step on the gas. The engine would keep running but I would have no power and although there is no choke in the vehicle it acted like an older vehicle with the choke not working. I took it to a local garage (not a dealer) and they could not find anything wrong. They suggested I take it to a Ford dealer and have it run through a diagnostic. This started just after I had filled with gas and lasted about a week. After filling with gas again the problem seemed to go away and I decided I had gotten a bad tank of gas. Well it has started doing it again. It also is backfiring, not loud bangs, but little popping sounds. I found when I just gave it gas slowly it would keep going, however if I try to accelerate it chokes. I am never quite sure I will make it where I am going. Any ideas what my problem is. Thanks.
Lets say you have done the obvious, and done a complete tune up? Either the timing is off or cam may be worn
October, 26, 2007 AT 2:42 PM
I have read that the problem could be the Idle Air Control Valve. It appears this can be cleaned. I would like to try that first. Could you tell me where to find this puppy and how to clean it. Thanks.
October, 26, 2007 AT 3:02 PM
If you have a bad idle the IAC would be questionable, If you have no codes, Check for vacuum leaks and timing. Get a can of gumout spray, spray vac hoses and intake manifold, if the idle changes you have found a leak.A compression test will tell if it's a cam or burned intake valve!
October, 26, 2007 AT 3:26 PM
Thanks merlin2021, I am not a mechanic, just a hanyman. To clarify, since getting the vehicle it has not started on the first try it will usually start on the second try though. (Not sure if this is at all related). The other day I even had trouble starting it and after finally starting it ran rough for a couple of minutes. It has started and idled OK before that and since. The problem with stalling happens when I put it into gear and depress the excellerator. It chokes but does not stop. It keeps doing this choking thing while driving. As I said in the beginning It did this same thing about a year ago and cleared up after a tank of gas. I have found in the last couple of days it has gotten a bit better. If I baby the excellorator and don, t step hard on the gas it will build up speed and seem to work OK.
October, 26, 2007 AT 3:34 PM
If it only happens on a cold start, check the ECT! This acts as the choke on SEFI models! Also try turning the key on for 3 secs then off then start, see if the starting improves, you may very well have a weak fuel pump! Get the pressure checked out! If the pump dies on these, it won't run again, till new one is installed!
October, 26, 2007 AT 7:06 PM
What does ECT mean. In the auto term abbreviation list that refers to the engine coolant temperature. Is that correct. You are correct, the vehicle does start better on the second try after waiting. Seems like its always been that way.
October, 27, 2007 AT 8:48 AM
Yes ECT=electronic coolant temp sensor. Pressure test and leak down test fuel pump too.
October, 27, 2007 AT 9:25 AM
Thanks merlin2021. You have given me several things to check. It would seem I will need special equipment to check these things, so I will probably have to take it to a shop. I will let you know hoiw this all pans out.