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Wally
05-04-2002, 19:18
I need some info so I can go armed :D to the dealer next week. I seem to have an issue with the carpet interfering with the throttle on the new truck. I've only got about 1/2" of pedal travel before it hits the carpet. I can mash it into the carpet and get more juice(sorry Mac). My dealers service writers are generally idiots. The service writer told me today that they could fix it by adjusting the throttle cable.#$@$$&*#@@ I smiled politely and told him I would be back next week when the manager and the driveability tech were there.
Question: Can the throttle position be read with the TechII? Can the throttle be calibrated,I.E.; adjusted so that less movement still inputs 100% to the ECM?
I've looked at the carpet and the throttle bracket and I don't see any adjustment there and if I notch the carpet then there is a piece of plastic under it that runs about 25 degrees parallel to the throttle movement and it looks like a great place to get stuck. Thats the last thing I need is a Dmax with the throttle stuck wide open.

Kennedy
05-04-2002, 19:24
Hook to the T2 and mat it as you would when driving. Note APP, and I'm quite certain it will be 98-100%. There is no adjustability, but I have "massaged" the lever. This is NOT something I suggest though as APP modules are $$$.

NutNbutGMC
05-04-2002, 19:32
Quote:
Thats the last thing I need is a Dmax with the throttle stuck wide open.
:end Quote

I'd love it as long as I had highway in front of me. :D

odoh
05-04-2002, 19:51
Perhaps a matter of interest was an experience w/my diesel rabbit. The daughter was complaining about no power. I didn't believe her and decided to drive it home where I could tinker w/it. I hit the accelleration ramp ~ bad, bad move. The pedal was touching the floor and the best it would do was 35 mph (even w/me hunching it along :rolleyes: ) and traffic flow was 55mph. Got home and determined that the cable had stretched a bit (not uncommon for a vehicle w/some mileage on it). A simple cable adjustment lifted the dang thang off the floor and it was good to go. So, I at least wouldn't be too hasty to dismiss the suggestion. Of course one could take a ballpeen hammer and pound the floor down a bit to increase pedal travel :D :D ~ odoh

[ 05-04-2002: Message edited by: odoh ]</p>

Kennedy
05-04-2002, 20:04
If the SM is talking about cables, he hasnt got a clue....

Wally
05-04-2002, 21:26
Thanks John,
Explain "mat" as I'm sure I will have to explain it to the tech. APP stands for?
How did you "massage" the lever.
For the rest of you. Look under your dash. The device that sends throttle commands to the ECM is all one unit with no cables! Not as simple as a potentiometer as it has more than three wires. PWM? With inputs for full open and fully closed? That would explain the extra wires.
One more question John: You say not adjustable. Physically I can see that it has no adjustment, but electronically?
One more observation; GM did a really good job of giving the drive by wire throttle a good pedal feel but I've noticed with this manual equipped truck rough roads and low speeds can be quite jerky because of my foot bouncing on the pedal. Any electronic damping available to soften those sharp quick inputs?

odoh
05-04-2002, 22:37
Throttle by wire? :confused: What have I gotten myself into? :eek: The average person will have to be married to the dealer for what apparently used to be normal(?) wear and tear maintenance/repair. Here I thot I was doing pretty good in securing an '02 rather than the new '03 w/its mulitiplex wiring system. I purchase a truck to last a long time 12 to 16yrs or more (my current was purchased new in '84). If one must rely on a dealer for every lil' thing and the dealer decides he can't/doesn't want to deal w/it anymore, we're like SOL. :( Just how long has this been going on? ~ odoh

Kennedy
05-05-2002, 09:29
Drive by wire has been around on GM diesels since 1994, and has worked very well. Ive heard of a few older trucks shelling APP modules, but few based on the number produced.

Mat is just like it sounds: Pin it to the mat

APP is Accelerator pedal position.

Im sure yours is working fine, and you are getting full APP value (100%) WELL before the pedal stops moving.

The only other note is that IF you depress the APP pedal at key up, and before the ECM looks at it, it will learn the mid travel position as 0% and not give 100%. This is particularly useful info for those having trouble resetting the oil minder. Wait till the diagnostic lights quit blinking...

AzKevin
05-05-2002, 09:54
kennedy,

Any idea if it's likewise true that one should wait for the diagnostic lights quit blinking before attempting to change Juice power levels?

Kennedy
05-05-2002, 09:59
Since it needs to see 100% APP, I'd say yes!

This is something I learned when doing TDC learn the hard way on the OBDII 6.5's. It required a KOEO APP sequence like the Edge, and it was really hit/miss until I realized what was happening.

You can actually start the engine under certain circumstances with the pedal on the floor and get nothing but an idle. PLEASE dont try this at home...

Wally
05-05-2002, 14:54
John,
Thanks for the info!
BTW, I must have missed something along the way. I notice your sig now says Chevy. Didn't you start out with a GMC?

Kennedy
05-05-2002, 17:46
I bought my '96 used, AND prefer the look of the GMC in the "Classic" style trucks. I bought the Chev locally at Domine Chev as I try to help the locals, and they help me. In the late style, I prefer the Chev as it shows more distinction over the 1500 series "puppy" trucks...

[ 05-05-2002: Message edited by: kennedy ]</p>