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Discussion Starter #1 (Edited)
So, this happened a couple of times last year, and it happened again Friday morning and again this morning, and I'm dreading that it might be starting to be a recurring problem...

Sometimes when I start my car after not driving overnight, or for a few hours, the throttle behaves strangely,

When I start off, I let out the clutch, and after I'm fully engaged, I roll the throttle on, and it only gives me full throttle for a split second before it acts like it is only giving about 1/4 throttle. I shift into second, and can even spin the tires going into second gear, but a half a second or so after I engage the clutch, with my foot buried in the pedal, it cuts back to 1/4 throttle again. I can modulate the pedal between 1/4 and fully depressed, and it stays at exactly the same level. When I let off, and up until a 1/4 it acts normally.

Air/Fuel and spark all seem to be fine, as it will run up to red line if I'm willing to wait for it to get there. I usually end up short shifting and using as much of the power surge after the shift as I can, but pretty much to no avail. I still end up merging like a 75 year old Asian woman. I can go 75mph or better, it just takes forever to get there.

BTW there is no check engine light.

I have not tried the throttle re-learn process yet as I am afraid that might make it worse, if there is an intermittent problem with the potentiometer in the throttle.

I'm guessing it's either ...

1. The electronics in the gas pedal
2. The motor that turns the throttle plate
3. A physical problem with the throttle plate
4. An intermittent but not serious problem with the throttle position sensor.

If anyone has insight into this problem, it would be much appreciated before I start replacing parts.

UPDATE:
Happened again this morning on my way to work, and was fine on the way home. Then it happened again tonight.

Another strange thing I noticed when I turned the car off was that when the ignition is on but the car is not running, with my headlights off, when I hit the brakes, my dash and hvac lights and the parking lights all come on with the brake lights.

I also pulled the check engine codes only to find 0000 (no codes thrown)
 

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Discussion Starter #2
So update and bump,

It only happens when it's cold outside. Car can be warmed up, turned off for a few minutes and started again, does not matter, if it's colder than about 60 degrees outside, the throttle has a problem.

Also, I tried the throttle re-learn, it didn't work.

Cruise control will not set during throttle problem times. It turns on, but when you hit set, the set light just flashes.

I also listened closely tonight while it was having it's problem, and it seems when the ignition is on, but the engine is not running, I can put it in first and roll my foot on the gas, and still hear the throttle plate moving. I can even hear it move well past the point where the throttle cuts out when I'm driving.

Does this have secondary injectors that may be failing in the cold weather?

I don't know where to go from here, but I'm going on vacation next week and I might just drop if off at a shop if I can't figure something out before then.
 

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Discussion Starter #3
Hello everyone,

Just located the problem...

I found this forum post http://forums.nicoclub.com/acceleration-problem-t495442-40.html#p5772969 (last post on the page)

and thought that maybe the brake light problem might be related, so I had my wife come out and turn lights on and off and hit the brakes.

I found that the brake lights were on when the parking lights were on. When I pulled one bulb, there was no change, but when I pulled the other one, my brake lights turned off, and with a quick test drive, I found that the throttle problem was gone as well.

Strange that a brake light short can cause you to have a problem with the throttle, but whatever, it's fixed, and now I know what to check for. Oh by the way, it's not the cold causing the problem, it's me using my headlights.

Thanks for the help guys (notice the sharp note of sarcasm).
 
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