So last night my friend and I were doing a 3rd gear roll...he in his '03 stock 350 and me in my '03 350 with Injen AI, Stillen Exhaust, JWT Flywheel and the UR Pulley Set...I began to pull him a little as I neared redline- as soon as I shifted into 4th the throttle respone to the motor was lost...the car remained running but when pushing the accelerator the motor reved EXTREMELY SLOWLY...I pulled over quickly and tried once again- push the accelerator and watch in fear as the tach/engine rpms moved very slow up and down the band...well, i turned off the car and hoped this would reset what had gone wrong...sure enough, she fired back up with instant response again WITH ONE EXCEPTION..."Service Engine Soon," ok- well, before I take it to service, can anyone tell me what may have gone wrong and what I should expect when taking it to the dealer...Thanks for the input=)

 

You entered safe mode.

How hard did you stab the throttle? I have seen the drive by wire throttle sensor (potentiometer) go out of range and cause this same event.

But it could be a number of things . . . get the code pulled. Let us know what you find.

 

I have had this exact same problem happen to me when I let my car sit over winter in my garage. I added some mods to it, ground wires, pulleys and a cold air intake. Well, after driving it around I started to get that problem. I would hold down the gas pedal and the car would just stop accelerating. It would hold the RPMS still and then slowly start to climb in engine speed. I have tried to figure out what the problem was but I am still getting it on and off, and now I have gotten the CEL this Monday. I would like to hear what you find out because now this will make it at least 4 people who have had the same exact problem and no one knows why. I don't have an OBD2 but I will get my car checked out on Saturday and post back.

 

One thing to try is the "Throttle Position Learning" procedure. I think a lot of people could possibly be affected to some degree by not performing this procedure after having had the battery disconnected for any period of time. The Service Manual instructs to do this every time the battery is disconnected or if the ECU has been removed and reinstalled. I noticed a big difference after I sent my ECU in for a reflash. I drove the car and I thought something just didn't seem right since I was expecting more gains, the car felt more stock like. Then I realized I forgot to perform this procedure and there it was!! Instant improvement in throttle response and performance. You can find the intructions here along with the ECU resetting procedure: http://www.technosquareinc.com/350reset.htm

 

thanks zzzya...i will try the instructions from Technosquare and will let you know the outcome...i just had it in the shop for a transmission replacement and i know the battery was disconnected for that...thanks again for the info...

 

To get the CEL codes, follow a similar procedure:

Turn the engine to run where the dash lights come on.
Count 3 seconds (you need a watch it is exact.)
after 3 seconds press and release the accelerator to the floor then 5 times in 5 seconds
wait 7 seconds
push and hold the accelerator to the floor for 10 seconds until the CEL starts flashing.

It will then blink 10 times (trust me w/o a watch it won't work).
Count the blinks, after 10 count the series of 3. 10 blinks = 0. Take code to: http://www.actron.com/code_lookup/index.php

Example:
3 seconds on
5 seconds push, repeat push
7 seconds wait
10 seconds push hold
10 blinks pause
1 blink
7 blinks
5 blinks
then the blink cycle loops again starting at ten
To clear press and hold the accelerator for a full 10 seconds then release then turn key off then restart, CEL is gone.

Enjoy.

 

im not sure if this has happened to me in my Celi or not but sometimes when i floor it it takes 4ever to get up there and sometime when i floor it it goes! although it's an already slow POS!