speed not increasing in relation to accelerator pressure

[Teresa King]

I had all the fluids and filters changed in my 03 ST XLT on November 6. It has 60,000 miles on it and I've not had any trouble with it at all. Until last Tuesday. It ran fine for 15 miles, I stopped and turned it off for about 15 minutes. Came back, cranked right up and when I stopped at a red light 1/2 mile later I thought wow, this thing seems to be running really rough. When I pulled out from the light I pressed the gas, the truck accelerated, but not at a speed relative to the accelerator being pressed down. It never actually died..but for the next 3 miles every time I tried to gas it very hard it would bog down. I stopped at a nearby autoparts store and a nice gentleman there checked out some electrical stuff - nothing. I cranked it back up, revved the motor while it was in park at about 3000 rpm it kind of misses..but fine til then. Drove it home - never getting aggressive with the gas pedal - no problems. Have driven it three times less than 2 miles each trip since then. No check engine light, no gauges showing a problem, nothing.

Any suggestions?

Thanks!!!

 

[Kevin Palmer]

First, there is a over-rev protection. If you are not in gear it will max out at 3000 RPM to prevent damage to the engine, hence the miss you have when reving it out of gear.



2nd, for some reason, the Trac seems to have a ghost glitch that just happens every now and then. It gets a miss and yet there is nothing wrong. Simply stop, turn it off, wait 30 seconds, restart it and your good to go.



It has to do with the ECM but no one has a concrete answer or fix for it.

 

[Richard L]

Theresa,

Yes, Coastiejoe is correct. There is a common gremlin in the Sport Trac's ECU's that will on rare occassions cause the engine to run very rought. They cure seems to be to just shut it off, and restart the engine and that will usually cure the problem.



I suspect that it might be that the vehicle was started before the ECU has had a change to complete it's boot up cycle.



My 2001 Sport Trac did it only once in the 3 years I owned it, and I found that turning the ignition on for a few seconds before cranking never caused the problem to appear again. I have had my 2003 Sport Trac for over 3.5 years and have never encounter the rough engine on startup.



...Rich

 

[Scott Heckler]

Replace the fuel filter if you have not already done so. It gave me the same symptoms.

 

[Teresa King]

Thanks for the help -We just returned from our holiday travelling - I had all the filters, including fuel filter, changed 7 weeks ago at the local dearlership. So I'm hoping it's the "ghost glitch" I'm going to drive it the next couple of days and see if it continues to run fine and go from there. I also had less than 1/4 tank of gas when it started this behavior...so I'll go fill it up today..maybe try premium and see if takes care of the problem. Thanks guys - have a happy new year!

 

[Chet 02]

Kinda going off topic here, but I just noticed that you are on Hartselle Teresa. What a coincedence!!! I lived in Hartselle for about 8 years until 1995 in the north end of town just off Hwy 31.

But that's not the only weird coincedence....I also drive a Zinc Yellow. It's a small, small world.