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- Joined
- Mar 24, 2013
- Messages
- 1,143
- Age
- 81
- City
- Renton, WA
- Vehicle Year
- 02 2X4; 08 FX4
- Transmission
- Automatic
2002 Ranger, 4l, Auto, 4 doors. No codes, none!! Sorry this is so long; but, I am at my wits end.
It has been having weird idle problems between drive/reverse and neutral/park for about the last 9 months. Otherwise it always ran great. First it would drop to 500 rpm when you shifted from drive or reverse to park or neutral (sometimes it would recover to 750 rpm, sometimes not). When you put it back in gear it would immediately go back to 750. IF you disconnect the IAC valve it dies immediately which I understand is normal. Changed the IAC (Napa, probably should have got a Motorcraft) and cleaned the MAF. Nothing changed; but, over several months it quit doing that???. I really don’t understand how having the Trans in drive or park has any bearing on idle speed, or why time fixed it. IF the computer wants 750 rpm, what does the transmission have to say about it?
Next, on cold start (off for over 2 or 3 hours) it began idling at 1000 rpm on start-up rather than the normal 1500. IF you let it run for say ten minutes, shut it off and restarted it would always go to the 1500 rpm for the normal 10 or 15 seconds and then drop to 1000 or 1200. After warm up it idled at the normal 750 rpm. It is parked in a garage that never gets below 40 degrees so I have just been watching it.
Couple of days ago, I noticed that with the AC on it would drop to 500 rpm and then immediately recover to 750 as the compressor cycled on and off. It didn’t used to do that and I don’t know when it started. But, here is the killer, it would only do that in neutral or park. IF it was in gear, it maintained the 750 rpm all the time. Again, what’s with the transmission interface???
And finally, last night it would not idle at all. You could feel it start; but, would not run. By feathering the throttle I could get it to run and got it home by two footing it. It ran really crappy, if you floored it felt like it just plain died, and there was a weird smell (sort of like running rich; but, not really). I just shut it off. The wife and I were coming home from dinner and drinks and I didn’t feel like messing with it.
This morning it started right up and idled at 1800 rpm. Dropped to 1200 as sensors came online. I shut if off put the old IAC back in just because. Started up and idled at 1500 rpm and dropped to 1100. Took it for a spin. It had a real flat spot and stumble at around 3000 rpm (responded well to WOT). As it warmed up the flat spot went away. It ran great and shifted normal. It does not have the idle drop between neutral and park; but, it still has the idle dip in neutral when the AC compressor cycles (but again, not when in gear).
So, what the hello is going on!!!! And what has the transmission got to do with it???
Again, sorry this is so long, Ed
It has been having weird idle problems between drive/reverse and neutral/park for about the last 9 months. Otherwise it always ran great. First it would drop to 500 rpm when you shifted from drive or reverse to park or neutral (sometimes it would recover to 750 rpm, sometimes not). When you put it back in gear it would immediately go back to 750. IF you disconnect the IAC valve it dies immediately which I understand is normal. Changed the IAC (Napa, probably should have got a Motorcraft) and cleaned the MAF. Nothing changed; but, over several months it quit doing that???. I really don’t understand how having the Trans in drive or park has any bearing on idle speed, or why time fixed it. IF the computer wants 750 rpm, what does the transmission have to say about it?
Next, on cold start (off for over 2 or 3 hours) it began idling at 1000 rpm on start-up rather than the normal 1500. IF you let it run for say ten minutes, shut it off and restarted it would always go to the 1500 rpm for the normal 10 or 15 seconds and then drop to 1000 or 1200. After warm up it idled at the normal 750 rpm. It is parked in a garage that never gets below 40 degrees so I have just been watching it.
Couple of days ago, I noticed that with the AC on it would drop to 500 rpm and then immediately recover to 750 as the compressor cycled on and off. It didn’t used to do that and I don’t know when it started. But, here is the killer, it would only do that in neutral or park. IF it was in gear, it maintained the 750 rpm all the time. Again, what’s with the transmission interface???
And finally, last night it would not idle at all. You could feel it start; but, would not run. By feathering the throttle I could get it to run and got it home by two footing it. It ran really crappy, if you floored it felt like it just plain died, and there was a weird smell (sort of like running rich; but, not really). I just shut it off. The wife and I were coming home from dinner and drinks and I didn’t feel like messing with it.
This morning it started right up and idled at 1800 rpm. Dropped to 1200 as sensors came online. I shut if off put the old IAC back in just because. Started up and idled at 1500 rpm and dropped to 1100. Took it for a spin. It had a real flat spot and stumble at around 3000 rpm (responded well to WOT). As it warmed up the flat spot went away. It ran great and shifted normal. It does not have the idle drop between neutral and park; but, it still has the idle dip in neutral when the AC compressor cycles (but again, not when in gear).
So, what the hello is going on!!!! And what has the transmission got to do with it???
Again, sorry this is so long, Ed
