Ghost in the Machine- Serious Throttle Fluctuation!

So, am I the only one with a throttle fluctuation problem?

Car throttle sensor was probably getting a bad input. My guess is the ECU spiked (something electrical got jacked up), when I had to jump start the car (again, for the third time- bitched about this in another thread, under electronics, but the problem didn't arise the first two times I jumped the car). But I'm not certain what caused the problem.

Conditions: Weather 34-36 degrees F. Snow on the ground. COBB SRI. Forge BPV (It was replaced with stock BPV, to see if it was the cause, but it wasn't).

Symptoms: The RPMs would jump from 800 to 1400 RPMs for no apparent reason at idle. While shifting the RPMs would remain constant, with no pressure on throttle, causing the engine to surge as the clutch is pressed. Usually the RPMs drop as soon as you release the gas and hit the clutch, but with this problem the throttle "thought" it was getting pressed, when it wasn't. VERY weird. Simply turning the car off and on, didn't make the problem go away.

Fix: Used Push-the-DSC-Button-Mod-before/during-start.

Problem went away with pushing the DSC button (Read in the good manual how DSC adjusts torque to road conditions. I assumed this might be controlled through the throttle.)

Haven't driven the car since.

A/C on?

sounds liek your throttle position sensor is about to take a s*** on you. Common problem with these stupid drive by wire cars

thats how my car idled when i forgot to plug my MAF back in !!!
im a dumb ass !!

Follow up:

Yesterday was the first time I drove her since Sunday. Absolutely no issue with fluctuation and the battery still had charge after 5 days of sitting in the garage all alone.

I'm guessing it was when I jumped started her, that the ECU picked up a bad reading, resulting to throttle fluctation... I wonder if a Autoexec grounding kit would help??

Anyway- I noticed that whenever I leave the bonnet (hood) open to cool the front clip (engine), the battery dies. I can't find anything that "turns on", when the hood is open. Does anyone else know? THX!

tru-boost said:

thats how my car idled when i forgot to plug my MAF back in !!!
im a dumb ass !!

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But that should have triggered a CEL. Did it go on?

Speedy3 said:

A/C on?

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Nope, but I've seen a similar problem with automatic trans Mazdas w/ AC on.

laloosh said:

sounds liek your throttle position sensor is about to take a s*** on you. Common problem with these stupid drive by wire cars

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I hope that's not the case, but that definitely does make sense. Another guess is that the Drive-by-wire throttle is designed with a bad ground, probably leading to possible accidents like the old Audi 5000 (I don't think they were drive by wire, but they had AT cars that accelerated on their own damaging property). I don't think Audi ever fully recovered from that fiasco. The Press totally ate their lunch. I hope it was just a fluke and it never fluctuates again, -good thing our cars are MT.