Throttle / Reprogram?

simoncpw · #1 04-30-2009, 09:14 PM

Hi all,

Does the DME/ECU need to be reprogrammed after the Throttle is replaced?

My car has been having the following intermittent problems:
1) While driving as per normal, I feel the throttle is not as responsive. If I press the gas pedal just a little bit, there's no response as if I didn't press the gas pedal at all or no additional fuel is given, or no additional power. But if press the pedal a little harder, it will response after about 1/2 sec.

This problem got worse yesterday, no response even if I press the gas pedal 1/4 to 1/2 way. So I pulled over, stopped... then the car shut itself down completely.

2) When trying to start up the car by turning from key position 0 to 3 (release the key immediately after engine is fired up, key returned at position 2, and NOT PRESSING GAS PEDAL manually ), the car will start up, but shut itself down immediately without being able to idle. Sometimes I could see the engine rev / RPM fluctuate between 0-1k trying to idle by itself (with me pressing the gas pedal)... but would still fail and shut down after a couple of sec.

If I press the gas pedal hard after engine start, the engine will response.... until I let the pedal go about 1/4 to 1/2 (or completely), it will die again without being able to idle.

I'm not sure if problem #1 and #2 are related: I have experienced #2 for a few months intermittently. Not sure if #1 has always been there and I just got a little more sensitive about it since I have been very stressed by #2

I decided to try another trustable workshop this time, after a day of checking... they said the throttle seems to be new (probably replaced by the previous owner)... and "reprogramming" of the DME / ECU might not have been down... and could cause the above problems.

Does this make sense at all? Sorry I'm not an Mechanic, but am interested to learn more

Thanks in advance.

killcrap · #2 05-01-2009, 06:32 AM

What kind of engine is this a v12? Let's get the details.

simoncpw · #3 05-01-2009, 09:56 AM

Sorry I should have mentioned this. It's a 2002 V6 4.6is.

Any suggestion will be much appreciated.

Thanks.

NyMench · #4 05-01-2009, 01:44 PM

Quote:

Originally Posted by simoncpw

Sorry I should have mentioned this. It's a 2002 V6 4.6is.

Umm that doesn't exist....unless you or some else put the 4.6is badge on the car........

Wagner · #5 05-01-2009, 01:51 PM

Quote:

Originally Posted by NyMench

Umm that doesn't exist....unless you or some else put the 4.6is badge on the car........

Well a V6 didn't exist, but a 4.6is in 2002 did.

simoncpw · #6 05-01-2009, 01:55 PM

I meant 2002 V8 4.6is

killcrap · #7 05-01-2009, 05:56 PM

check the diagnostic request of the pedal position sensor. sweep the pedal and check the readings, there may be a dead spot.

simoncpw · #8 05-01-2009, 08:50 PM

Thanks for the advice. If there's a dead spot, would this dead spot be intermittent or permanent? The most stressful thing about this problem is that it's intermittent.

Quote:

Originally Posted by killcrap

check the diagnostic request of the pedal position sensor. sweep the pedal and check the readings, there may be a dead spot.