Low rpm surging-anybody experienced this?
#1
Low rpm surging-anybody experienced this?
Sometime at low rpm, my truck surges (the acceleration). During these times, my foot is always at a constant pressure on the accelerator and generally not pressed any more thant 1/4 throttle. It is more prevalent when I am going uphill (especially from a stop), or under a load of some sort. I thought it might have something to do with the fuel pump or possibly the computer mapping. Has anyone experienced this? Fixes?
#3
Senior Member
Surging
Just started seeing this on a 97 4.6L 4x2, 160K miles. Been well maintained by my mechanic. Starting about 3 weeks ago, sitting at a stop light, foot on the brake, nothing on the accelerator, rpms will be around 550 rpms, then every 10 seconds or so will increase by about 250 rpms for 3 or 4 seconds then drop again. Already put a can of injector cleaner through it, no change. Still looking for possible causes of this.
No ac, no heater on, nothing out of the ordinary other than being stopped and foot on the brake.
No ac, no heater on, nothing out of the ordinary other than being stopped and foot on the brake.
#5
I should have mentioned its a 2004 5.4L.
The acceleration surges, but not the rpm's on their own.
I don't think I really have that many vacuum hoses, and it only happens every once in a while. I was hoping its not a computer problem, but perhaps it is. Maybe tranny?
The acceleration surges, but not the rpm's on their own.
I don't think I really have that many vacuum hoses, and it only happens every once in a while. I was hoping its not a computer problem, but perhaps it is. Maybe tranny?
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#8
Now on a serious note, with your truck being a 2004, it is just old enough to begin routine problems if the schedule service checks have not been met.
Such as plugs, wires, fuel filter, PCV, even an O/2 sensor, I would recall if any of these had or have been changed & begin here.
You did not list if any of these have been replaced, the miles on the engine, or if you have had your CEL come on.
It does sound like a minor problem now & hopefully you can nip it in the bud before it does leave ya on the side of the road.
I beleive Ford is an awesome truck, but like any, we need to keep them maintained.
Good luck & best to you
#9
The truck has 100,000 miles on it (I was sweating the day the plugs came out) and has had all scheduled service done to it. No CEL has ever come on. The rpms surge with the acceleration, but never by itself .
I have a good mechanic I regularly take it to, but I'm out of the area right now and I kept on forgetting to mention it to him because of how infrequently it happened. The first time it happened I figured it was some sort of computer hiccup. It didn't happen again for a long time so I forgot about it. Now in the approximately 6 months I've had it, it's happened probably three times. I thought maybe somebody else had experienced this and I could give my mechanic some leads next time I saw him.
I have a good mechanic I regularly take it to, but I'm out of the area right now and I kept on forgetting to mention it to him because of how infrequently it happened. The first time it happened I figured it was some sort of computer hiccup. It didn't happen again for a long time so I forgot about it. Now in the approximately 6 months I've had it, it's happened probably three times. I thought maybe somebody else had experienced this and I could give my mechanic some leads next time I saw him.