Car Hits 7000rpm on its own

[tannerc91gt]

ok heres my problem, i have a 91 5.0 with a 5-speed and
in traffic today slowing to a stop my car hit 7k rpm in neutral.
it "held itself to the floor" for what seemed like forever but couldnt have been more than 7 seconds. car is fine no thrown rods or anything just dont want to take the chance of it happening again.

the only thing i can think of is if the throttle is sticking open or the cruise control is glitching and when i shift into neutral its flooring the gas pedal trying to keep it up to speed. I wouldnt think the ECU would let the car hit 7 grand though

 

[85_SS_302_Coupe]

You definitely shouldn't have revved that high with the stock ECU...shouldn't bounced at 6250.

 

[tannerc91gt]

thats exactly what i was thinkin, not sure on the full history of the car it may have been tuned at some point in the past, but it was buried at 7k so it may have been higher than that.

 

[FastDriver]

Most stock tachs will show a higher reading than actual. Most likely you were not at 7k... That would be very likely to cause Piston-valve contact.

Were you just idling when it happened? If not, what were the circumstances. What were the last things you did before it happened?

 

[tannerc91gt]

I was runnin at probably 60mph slowing down to a stop. I was probably at 25 mph when I kicked it into neutral and that's when the rpms skyrocketed and held it there. It did sound like it was tapping the rev limiter but it just continued to hold it there. It stopped after about 8 second and then continued to idle at the stop light normally and didn't seem to act odd at all

 

[85_SS_302_Coupe]

In all reality if your engine is stock and your valvetrain is stock, i doubt that it would actually rev to 7k without some serious valve float. If it did and it stayed there for 7 seconds i would expect something bad to happen.

 

[tannerc91gt]

Well other than headers the motor is stock as you can see in my sig but it topped out on its own and that's the problem, even if was at 6250 instead of 7k that's still a problem
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[5.0TailPipeHump]

tanner ' was there a car pulling up beside you and you went into kill mode and held the gas pedal for 7 or 8 seconds' lol man that must have been some crazy ***** with a flowmaster set up.

Check your throttle cable.

 

[tannerc91gt]

Yea, throttle cable and spring are fine, unless its snagged through the firewall but I'd seriously doubt that, oh and the car beside me was a honda oddessy, good call though
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[Mustang5L5]

Caught on the floormat??

 

[90lxcoupe]

check the spring on the tb, I've seen them get pretty loose after time. Also, were you using your cruise control around the time it happenend? The reason i ask is back wen i had cruise control, if i left it on and kicked the clutch in, a second later the RPMS would slowly start climbing, but whatever it is, you should figure it out, cause that could cause you a serious problem, if you float a valve, and it touches the piston, this could happen...

 

[benH2024]

across the board fords have a problem with idle air control valves that causes irregular reving try and replace it and see if that fixes your problem.

 

[Krakah94GTVert]

Caught on the floormat??

BINGO! This happened to me. Scared the crap out of me.

Another way this could happen, especially with a 5 speed is with the cruise control. You said you were driving @ 60mph or so. If you drive around a lot with out using the clutch like i do this can happen.

If your cruise is on, and you take the car out of gear to slow down w/ out using the clutch it will give the car gas automatically trying to speed back up. The cruise is deactivated by the brake and gas pedal.

 

[tannerc91gt]

I would say it was the cruise control then because I usually just pull it out in like 3rd and cost to the stoplight but I guess if I wasn't using the clutch then what you said probably happened.you wouldn't think the car would try to catch up so fast though