LamLamb
New Member
- Joined
- October 3, 2015
- Messages
- 5
- Reaction score
- 0
- City, State
- Georgia
- Year, Model & Trim Level
- 1998 Ford Explorer
Vehicle: '98 Explorer - 4.0L V6 - Pushrod (overhead valve) - auto - 143K Miles
I'm hoping that someone has had an experience like this before and might know what the issue is. Anyway, the engine has a problem when under load at low rpm. Sometimes it happens and sometimes not. Basically, the engine bucks/kicks/jerks under high load, low rpm conditions. It happens is rapid pulsations, like 2-3 per second until the load is reduced. If I reduce the throttle, it seems to "behave" again. You can feel it in the whole truck when the torque converter is locked up, and when it's not, the rpm dips and flares. I pretty much have to keep it under 2000 rpm all the time. I tried putting 93 octane in it and that doesn't help at all. Sometimes, I give the engine a few good revs in neutral after I get where I'm going and the engine is warmed up. (full throttle to 3200-3500 rpm) It seems to be aggravated when the headlights are turned on, but I'm not sure. I know for a fact that it's worse when the weather is foggy, and it's guaranteed to happen when it sits longer than 72 hours and the engine hasn't run. Also, it has a very rough idle after startup whenever the problem manifests. Sometimes It starts up and runs fine the whole trip, and sometimes it acts up. It definitely has a coolant leak but I can't figure out where it is. It also has an oil leak but its just an average leak that you would expect from an 18 year old engine. The cylinder 1 O2 sensor went bad and was replaced about 2 years ago, and the problem seemed to crop up some time after that. No check engine light though.
Any suggestions?
I'm hoping that someone has had an experience like this before and might know what the issue is. Anyway, the engine has a problem when under load at low rpm. Sometimes it happens and sometimes not. Basically, the engine bucks/kicks/jerks under high load, low rpm conditions. It happens is rapid pulsations, like 2-3 per second until the load is reduced. If I reduce the throttle, it seems to "behave" again. You can feel it in the whole truck when the torque converter is locked up, and when it's not, the rpm dips and flares. I pretty much have to keep it under 2000 rpm all the time. I tried putting 93 octane in it and that doesn't help at all. Sometimes, I give the engine a few good revs in neutral after I get where I'm going and the engine is warmed up. (full throttle to 3200-3500 rpm) It seems to be aggravated when the headlights are turned on, but I'm not sure. I know for a fact that it's worse when the weather is foggy, and it's guaranteed to happen when it sits longer than 72 hours and the engine hasn't run. Also, it has a very rough idle after startup whenever the problem manifests. Sometimes It starts up and runs fine the whole trip, and sometimes it acts up. It definitely has a coolant leak but I can't figure out where it is. It also has an oil leak but its just an average leak that you would expect from an 18 year old engine. The cylinder 1 O2 sensor went bad and was replaced about 2 years ago, and the problem seemed to crop up some time after that. No check engine light though.
Any suggestions?
