2003 LX High Idle warm or cold

[mundy5]

Folks,

I have taken a look at some posts and have done the following:

Cleaned the IAC and sprayed some WD40 on the slider; no change in high idle

Unplugged the TPS and the idle returns to a normal idle but my Traction Control off light is on (I presume since it can't figure out where the trottle is, it would automatically disengage).

So my question is the following: Can I clean out the TPS somehow or is it just better to replace it?

by the way, it seems to have high idle around 1500 in park whether its cold or warm. In drive it is around 1000.

Looking forward to hearing from some of you.

[mundy5]

quick update. I removed the tps and messed around with it making sure it's moving correctly etc. it's a pretty straightforward sensor and I really doubt that it breaks. nothing really electrical to break in there. so i put it back in and now the van is idling properly. took it for a short test drive and seems to be good. maybe i reset the traction control since both lights stayed lit for about 2 extra seconds and then turned off.

i wonder if my recent change in driving is affecting this. i am trying to apply some principles of hypermiling on the van to conserve fuel so i am accelerating really slow and going slow in general.

[diclemeg]

Originally Posted by mundy5

quick update. I removed the tps and messed around with it making sure it's moving correctly etc. it's a pretty straightforward sensor and I really doubt that it breaks. nothing really electrical to break in there. so i put it back in and now the van is idling properly. took it for a short test drive and seems to be good. maybe i reset the traction control since both lights stayed lit for about 2 extra seconds and then turned off.

i wonder if my recent change in driving is affecting this. i am trying to apply some principles of hypermiling on the van to conserve fuel so i am accelerating really slow and going slow in general.

MUNDY5, im having exact same problem. are you sure this messing with the TPS sensor worked ? i replaced mine completely and nothing changed.

[mundy5]

Originally Posted by diclemeg

MUNDY5, im having exact same problem. are you sure this messing with the TPS sensor worked ? i replaced mine completely and nothing changed.

I'm not sure if it is a permanent fix. I did test drive it today and it has a more normal range of idle rpms.

one way i tested to see if the tps was part if not the whole problem was by removing the connector to it while the car was idling and it idled within the 1000 rpm range instead of the 1500 or 2000 rpm in park. so i figured i needed to remove it and make sure it was working correctly. it turned out to be turning properly so I reconnected it and it is now idling properly. only time will tell.

why don't you turn on the van and see if the idle drops when you disconnect the tps sensor.

for all i know, this could be only a temporary fix and we might need to investigate further.

[diclemeg]

Originally Posted by mundy5

I'm not sure if it is a permanent fix. I did test drive it today and it has a more normal range of idle rpms.

one way i tested to see if the tps was part if not the whole problem was by removing the connector to it while the car was idling and it idled within the 1000 rpm range instead of the 1500 or 2000 rpm in park. so i figured i needed to remove it and make sure it was working correctly. it turned out to be turning properly so I reconnected it and it is now idling properly. only time will tell.

why don't you turn on the van and see if the idle drops when you disconnect the tps sensor.

for all i know, this could be only a temporary fix and we might need to investigate further.

ok, will do. but one question... after you forgot to attach a vacuum line, how exactly did the van behave? would it high idle only when cold ,but then, when at full op temperature, it would behave normally, or close to it, maybe a few rpm higher than should be, around 900rpm ? when it was cold, would it gradually accelerate on its own, and feel like, at any speed, it would coast forever? im hoping your answer is yes, because then that would mean we have same problem and that i missed a vacuum line when i searched for a leak when i took of the cowl looking for one, and that i have a simple fix. note that i have not had any codes, nor have replaced the gasket/isolator bolts.

[mundy5]

Originally Posted by diclemeg

ok, will do. but one question... after you forgot to attach a vacuum line, how exactly did the van behave? would it high idle only when cold ,but then, when at full op temperature, it would behave normally, or close to it, maybe a few rpm higher than should be, around 900rpm ? when it was cold, would it gradually accelerate on its own, and feel like, at any speed, it would coast forever? im hoping your answer is yes, because then that would mean we have same problem and that i missed a vacuum line when i searched for a leak when i took of the cowl looking for one, and that i have a simple fix. note that i have not had any codes, nor have replaced the gasket/isolator bolts.

I am not sure what vacuum line you are talking about. When I first did the P171/174 repair, I forgot to attach a vacuum line in the back of the upper plenum and I had a really rough idle.

In this case, I never even checked for a vacuum leak. I was simply cleaning up the IACV and it didn't fix anything. Still high idle. So I decided to unplug the TP sensor and immediately the car's idle dropped to the normal range roughly 1000 rpm in park. When I plugged it back in, it took maybe 5 secs b/4 it rose again to 1500 rpms. So I figured the TP sensor is telling the computer that the throttle is being pressed.

So I took the TP sensor out and made sure it was turning properly and then reinstalled it. Now, it seems to be idling normally.

My symptoms were simple. Whether it was hot or cold, the car would idle in Park at 1500 - 2000 rpms. At drive, it would idle at least 1000 rpms. This is without the a/c on. So I knew something was wrong. Normally, at a stop with the van in drive, it should idle in the 6-700 rpm range.

My symptoms were not exactly the same as yours but I really didn't test all the different situations. But one thing was the same, when driving, I would let go of the accelerator and it would travel around 35 - 40 mph without my foot on the gas. That concerned me.

Here is what I would recommend you do.

Start up the car and wait until it is warm. Put it in park and check the tach.

Make note of the rpms.

Then disconnect the TP sensor and see if the idle drops to say 1000 rpms. That's what it should be, I think, in park.

Then reconnect the TP sensor and within 5 secs, the idle should go back up to 1500 - 2000 rpms.

If this is so, then you have the same symptoms as me. Let me know.

[mundy5]

diclemeg, any updates?

[diclemeg]

Originally Posted by mundy5

diclemeg, any updates?

hi mundy,
yes, i didn't get back to you yet because i had a development that im trying to nail down with a few experts....

i attached a scan tool, and my absolute throttle position is 18% when im not touching the pedal. ive learned that the tps sensor resistor itself is fully functioning. however to connect the tps sensor to the throttle lever, it has to be seated about 18% open to able to screw in the bolts, and im trying to find out is if that is by design, and if the computer takes that at absolute zero. i will do this by testing a friends windstar with my scan tool. if its the same as mine, then i will test the voltage on the line, maybe the previous owner who installed the remote start system clipped the wrong wire, and sending errant voltage to the pcm.

my short and long term fuel trims were good, so theres no leaks. either way, ford is really pissing me off. they make some really good components that won't fail forever, and then do such stupid things like putting plastic isolator bolts on the intake spacer.

i will keep you posted.

[diclemeg]

message continued....

mundy, read above message first...

i forgot to mention.. my old tps sensor went bad completely. they are potentiometers i beleive, and you cannot clean it, but you can clean the electrical connector with electric cleaner, but thats hardly ever a problem. there might be a chance you put your tps sensor back on wrong, and is why it stays open in park. to put it on correctly, you have to tilt it to the right to get it on the plastic lever properly, and then slide it on, then turn it slightly to left to get the screws aligned.

[mundy5]

Originally Posted by diclemeg

i attached a scan tool, and my absolute throttle position is 18% when im not touching the pedal. ive learned that the tps sensor resistor itself is fully functioning. however to connect the tps sensor to the throttle lever, it has to be seated about 18% open to able to screw in the bolts, and im trying to find out is if that is by design, and if the computer takes that at absolute zero.

I'm not sure about the 18% but I definitely noticed that it requires you to turn it to the left after you attach it to get the screws in there. I was checking the FSM CD and it said that its minimum voltage should be 0.49 V or so and the computer must take that as its minimum and it maxes out at 5 V.

Originally Posted by diclemeg

there might be a chance you put your tps sensor back on wrong, and is why it stays open in park. to put it on correctly, you have to tilt it to the right to get it on the plastic lever properly, and then slide it on, then turn it slightly to left to get the screws aligned.

Actually, this was the first time I was messing with the TP sensor so I don't think it was put on incorrectly. I think what happened is that by removing the sensor, I must have reset something and maybe that's why it's idling properly now. It has been for the last few days.

It's a bummer that your TP sensor doesn't appear to be a problem. There is a test with the key on the on position but the van not started, you can move the throttle and it should read a continuous increase in voltage from .49 - 5 V. But since yours is new, I really doubt that your problem lies there but it never hurts to check.