Take foot off gas... car won't stop

[Linctex]

Originally Posted By: MinamiKotaro
Electric throttle? It will stay partially open until you hit the brake or coast below some pre-set speed. Something to do with economy and emissions.


This.

His throttle body is "fly by wire" - the computer controls everything. No dashpot or "shock absorber", no Idle air control either

 

[Linctex]

Originally Posted By: wallyuwl
When started from cold, the RPMs are about 1500 for a minute or so and the engine cooling fan in the front by the radiator is on very high.


Turn the A/C off before starting. A/C use makes the fan run.

 

[Nick1994]

Originally Posted By: Linctex
Originally Posted By: wallyuwl
When started from cold, the RPMs are about 1500 for a minute or so and the engine cooling fan in the front by the radiator is on very high.


Turn the A/C off before starting. A/C use makes the fan run.
Clutch fan

 

[SwampSurvivor]

Originally Posted By: bdcardinal
My manual cars have always slowed on their own when I let off the throttle and keep the clutch engaged.


My focus is awful, thanks to the EPA.

If I'm going 55, shove it in 3rd gear and let off the gas ... it will keep going 55

 

[wallyuwl]

Originally Posted By: Nick1994
It's got a fan clutch, they lock up usually when they go bad, they were very problematic in the first few years of the Trailblazer, Envoy, etc.

Time to replace the fan clutch, need to get it from the dealer.

I wonder if the fan clutch is locked up and the drag of the fan is making the car compensate and give it extra throttle.


If the fan clutch is locked up, would the fan be on all the time? Because it is only on for a minute or so at startup to go along with the higher RPMs. The RPMs can be as low as 700 or 800 while I should be coasting with my foot off the gas.

I've had vehicles before that slow down slowly, but this will literally stay at the same speed for miles with my foot off the gas until I brake.

I'm thinking of replacing the throttle body and lubing the cable and hoping that fixes it.

 

[DoubleWasp]

Originally Posted By: Nick1994
Originally Posted By: Linctex
Originally Posted By: wallyuwl
When started from cold, the RPMs are about 1500 for a minute or so and the engine cooling fan in the front by the radiator is on very high.


Turn the A/C off before starting. A/C use makes the fan run.
Clutch fan


Electronic clutch fan.

Computer has complete say-so.

 

[Nick1994]

Originally Posted By: wallyuwl
Originally Posted By: Nick1994
It's got a fan clutch, they lock up usually when they go bad, they were very problematic in the first few years of the Trailblazer, Envoy, etc.

Time to replace the fan clutch, need to get it from the dealer.

I wonder if the fan clutch is locked up and the drag of the fan is making the car compensate and give it extra throttle.


If the fan clutch is locked up, would the fan be on all the time? Because it is only on for a minute or so at startup to go along with the higher RPMs. The RPMs can be as low as 700 or 800 while I should be coasting with my foot off the gas.

I've had vehicles before that slow down slowly, but this will literally stay at the same speed for miles with my foot off the gas until I brake.

I'm thinking of replacing the throttle body and lubing the cable and hoping that fixes it.
It depends, the fan clutch should road on cold startup for a very short time, 1 minute tops. But it shouldn't be that loud. When you put it in drive and drive away, is it really loud pulling lots of air?

Originally Posted By: DoubleWasp
Originally Posted By: Nick1994
Originally Posted By: Linctex
Originally Posted By: wallyuwl
When started from cold, the RPMs are about 1500 for a minute or so and the engine cooling fan in the front by the radiator is on very high.


Turn the A/C off before starting. A/C use makes the fan run.
Clutch fan


Electronic clutch fan.

Computer has complete say-so.
To an extent. In 118+ degree heat I've never heard the fan clutch make hardly any noise in it, and I drive it a lot. The old fan clutch never engaged and it ran hot. Put in a new one and temp never goes above 1/3, you can hear it at startup for 30 seconds or so.

A/C use doesn't make it spool up anymore that you can hear it, including on a cold start.

But when these go bad, the computer can't tell it anything because it's locked up roaring like a jet engine.

 

[L_Sludger]

A badly adjusted throttle position sensor on my former Supra once made the car drive as if my foot was on the gas even when my foot was off the gas.

 

[AVB]

I cleaned the throttle body on a '08 Silverado recently that we had to take to the dealer to get the idle relearned after. We even installed a new throttle body to make sure that it wasn't the throttle body itself. That may be the issue with yours, but you would think that it would have relearned on it's own by now.

 

[HangFire]

My '99 Taurus, on a level road, foot off the gas entirely, would upshift through the gears and you'd find yourself going 45-50mph after a minute.

I asked 2 dealers to look at it and they wouldn't even charge me money to look at it- "that's they way they're made now".

You could watch the Tach and see the RPM's bump UP after every upshift.

I went through a LOT of front brakes.

5MPH? Phbt!!!

 

[wallyuwl]

Today I started it up and the fan roared for about 30 seconds, then quieted down. It was not loose on the axis. So maybe the fan clutch is good?

I did notice that one of the hoses that runs from the air box on top of the valve cover, to the valve cover, is missing. It would have been missing since I've had the vehicle two months. Maybe this is causing loss of vacuum and what is leading the car to keep going without my foot on the gas?

 

[SwampSurvivor]

Originally Posted By: HangFire
My '99 Taurus, on a level road, foot off the gas entirely, would upshift through the gears and you'd find yourself going 45-50mph after a minute.

I asked 2 dealers to look at it and they wouldn't even charge me money to look at it- "that's they way they're made now".

You could watch the Tach and see the RPM's bump UP after every upshift.

I went through a LOT of front brakes.

5MPH? Phbt!!!


My 01 was the same way!

 

[ARCOgraphite]

Classic Air leak. Glad you are checking for vacuum wellness first.

This is not a hard process just a rigorous process.

Logical thought.

 

[wallyuwl]

Originally Posted By: ARCOgraphite
Classic Air leak. Glad you are checking for vacuum wellness first.

This is not a hard process just a rigorous process.

Logical thought.

So I think that hose missing was the problem. Got it for $2 from the junk yard yesterday, and now the idle and fan speed at startup is fine. The vehicle slows down when I take my foot off the gas. Although, between 20 and 30 mph it does so very slowly (the RPMs are about 1000 in this range without being on the gas, which does seem a bit high). I think this is just the way it is, though. Previously if I was going, say 27 and braked to 24 mph or so, it would actually accelerate back up to 27. It doesn't do that anymore. I guess there still could be an issue with the throttle body or something inside it (idle control valve, maybe), but usually problems with those throw codes and there are none.

 

[Kestas]

Originally Posted By: Miller88
Originally Posted By: HangFire
My '99 Taurus, on a level road, foot off the gas entirely, would upshift through the gears and you'd find yourself going 45-50mph after a minute.

I asked 2 dealers to look at it and they wouldn't even charge me money to look at it- "that's they way they're made now".

You could watch the Tach and see the RPM's bump UP after every upshift.

I went through a LOT of front brakes.

5MPH? Phbt!!!


My 01 was the same way!

I too have have an 01 Mercury Sable with poor deceleration.
Coming off the freeway I'll sometimes shift into neutral for a moment and watch the rpms jump to 1700 before it slowly works its way down. Other cars don't do that.
It is not a vacuum leak.
It is not a bad IAC motor.
It is not a poorly adjusted TPS.
It is not a product of "efficient coasting."
It goes away temporarily after I disconnect the battery, only to return after a while when the computer relearns my driving.
Nobody online seems to know what the fix is.

 

[SwampSurvivor]

Originally Posted By: Kestas
Originally Posted By: Miller88
Originally Posted By: HangFire
My '99 Taurus, on a level road, foot off the gas entirely, would upshift through the gears and you'd find yourself going 45-50mph after a minute.

I asked 2 dealers to look at it and they wouldn't even charge me money to look at it- "that's they way they're made now".

You could watch the Tach and see the RPM's bump UP after every upshift.

I went through a LOT of front brakes.

5MPH? Phbt!!!


My 01 was the same way!

I too have have an 01 Mercury Sable with poor deceleration.
Coming off the freeway I'll sometimes shift into neutral for a moment and watch the rpms jump to 1700 before it slowly works its way down. Other cars don't do that.
It is not a vacuum leak.
It is not a bad IAC motor.
It is not a poorly adjusted TPS.
It is not a product of "efficient coasting."
It goes away temporarily after I disconnect the battery, only to return after a while when the computer relearns my driving.
Nobody online seems to know what the fix is.


They do it from the factory, unfortunately.

My 2011 Focus is horrible. If it's cold, the engine HAS TO run at 2500RPM. Doesn't matter if it's in gear or neutral. The 01 F350 will also rev up to 2000 when it's cold.

"It's a ford thing" is the best way I can put it.

 

[Kestas]

I also had problems with my 91 Mercury Marquis, only it was the opposite. When the temperature outside dipped below 25°F, the car would start at low idle and stay there... not the usual high idle that settles down after a minute. The cold start idle was even lower than the normal sitting-in-traffic idle.

So, we just covered Ford idle problems in 1991, 2001, and 2011. Why can't this company get it right? You'd think they'd have figured it out after 20 years!