Cold idle problem on 93 Explorer
Thread Starter
|
New User
Joined: Jan 2006
Posts: 10
Likes: 0
Cold idle problem on 93 Explorer
First of all, I want to thank those who've posted here in the past. I had a rough running motor and replaced my IAC and MAF sensors, solving the biggest problem.
When warm, the truck runs great. But, when it first starts up, the idle is very low (approx. 350-400 RPM). I keep my foot on the gas, and it eventually will eventually get warm enough, and run by itself.
Was thinking about changing the TPS (Throttle Position Sensor), since it's only $25. Any thoughts on other possible problems? I have a replacement PCM (Powertrain Control Module), but don't think that's the problem.
Also, may need the thermostat replaced. It doesn't overheat, but the temp goes to about mid deflection, then the temp drops off (assuming the thermostat opens). Might be normal, but I don't remember my other Explorer doing this....but it's been a long time.
Thanks again for your help.
When warm, the truck runs great. But, when it first starts up, the idle is very low (approx. 350-400 RPM). I keep my foot on the gas, and it eventually will eventually get warm enough, and run by itself.
Was thinking about changing the TPS (Throttle Position Sensor), since it's only $25. Any thoughts on other possible problems? I have a replacement PCM (Powertrain Control Module), but don't think that's the problem.
Also, may need the thermostat replaced. It doesn't overheat, but the temp goes to about mid deflection, then the temp drops off (assuming the thermostat opens). Might be normal, but I don't remember my other Explorer doing this....but it's been a long time.
Thanks again for your help.
Posting Guru
Joined: May 2002
Posts: 2,450
Likes: 2
From: Baltimore
Pull the codes... that should tell you if you have a TPS problem. If the temp gauge goes all the way back to "C" after hitting mid range, and then back to mid range, it sounds like the Tstat is opening and closing too quickly. Suggest replacing it. Easy repair.
Post Fiend
Joined: Feb 2003
Posts: 6,940
Likes: 2
From: Eastern WA
Pulling the codes is the next logical step. If there are no codes, I'd run pinpoint diagnostics on the coolant temp sender (sensor for the ECM, not the gauge) and the TPS. The reason for running the pinpoint diagnostics on the coolant temp sender is that if it's out of range a bit then it's possible that the ECM is not able to detect that it's a cold engine. This will result in a lean mixture until it's warmed up. It should throw a code if there is a problem but if there is no code I'd still check and rule this item out.
I'd agree on the thermostat replacement. On the 4.0, I've had the best luck with the ones from the Ford parts department as opposed to aftermarket brand. My aftermarket experience on this part, and a name brand, was that the "new" thermostat was sticking just like the old one and causing a fluxuating engine temperature. When installing, make sure you orient the bleeder at the 12'oclock position to facilitate purging air from the cooling system.
I'd agree on the thermostat replacement. On the 4.0, I've had the best luck with the ones from the Ford parts department as opposed to aftermarket brand. My aftermarket experience on this part, and a name brand, was that the "new" thermostat was sticking just like the old one and causing a fluxuating engine temperature. When installing, make sure you orient the bleeder at the 12'oclock position to facilitate purging air from the cooling system.
Last edited by CowboyBilly9Mile; Feb 10, 2006 at 02:25 AM.
Thread
Thread Starter
Forum
Replies
Last Post
Antiquer88
Explorer, Sport Trac, Mountaineer & Aviator
5
Sep 1, 2016 10:23 PM
ezstyles
1973 - 1979 F-100 & Larger F-Series Trucks
7
Jan 8, 2015 04:28 PM
Sassehole
1987 - 1996 F150 & Larger F-Series Trucks
11
Jan 22, 2013 02:17 PM
05victorylly
1987 - 1996 F150 & Larger F-Series Trucks
12
Mar 31, 2012 08:42 AM
