Tig

iTrader: (2)

I had gone over this with my tuner and he had said he did not mess the with the throttle tables.

My wife brought it up today. We were going to park in a parking lot, slowed down as we found a spot. When I started to accelerate we almost spun the tires pulling into the space. This has been a constant issue and I have no idea how to explain it to the tuner.

The last time the tuner and I went out I tried to explain it, he had his pc hooked up and every time it happened he didn't see anything. Not really sure what he would see but, that's what he said.

Does anyone else have this problem or know what could cause this lunging from a stop?

Thanks

DrX

iTrader: (7)

Throttle will only do what the tune tells it to, otherwise REP mode will be triggered. What are the details on the vehicle?

Tig

iTrader: (2)

Hi DrX, thanks for the reply.

Its an 07 Tahoe PPV. Stock accept for a tune, shift kit junior and FTI Billet 2800/3000 stall.

What is REP mode?

Thanks again, I appreciate the help.

DrX

iTrader: (7)

If the throttle does not go to the commanded position, the measured/calculated airflow does not match what is expected for the indicated throttle position, or other parameters don't match, then Reduced Engine Power mode will be triggered. This shuts down power to the electric throttle motor, so that the blade just sits at the spring-determined position which is around 18-20%. The engine has to be shut off for 15-30 seconds(depends on model year) in order to clear REP mode and re-activate the throttle. Or you can clear it with a scan tool.

Commanded throttle position = pedal position X throttle response tables X other modifiers in the tune.

Other than modified throttle response tables, a larger throttle body or corrupted tune file could cause increased throttle response. Other tune or mechanical issues may cause a surging condition.

Tig

iTrader: (2)

The tuner told me he did not alter any of the throttle response tables and typically does not mess with them in general.

It sounds like my tune or mechanical issues are the only options.

Is this something that can be seen with a scan tool or laptop?

Thanks again Dr

01WS6/tamu

iTrader: (36)

Flash it all back to stock using gm software and see if the problem goes away. If it does then a tune file is corrupted. If the file is corrupted then flashing it to the saved original tune from your truck when he flashed it wont help a thing. Only thing to do is start over with fresh OE flash to base line it.

DrX

iTrader: (7)

Yes, with the engine still stock, you can just flash back in a stock tune file to rule out anything in the tune.

Tig

iTrader: (2)

Unfortunately this has been my biggest hurdle.
The shop who tuned my truck the first time never saved my original tune file.
The second shop has been piggybacking off of what the first shop did.
I have been to several dealers in my area and they have no clue what's going on. All they say is to replace my trans and converter.

I did however just come from a friends house who said he now's someone who is capable of flashing it back to the stock tune file. Well, its a friend of a friend. I'm waiting for him to get back to me.

01WS6/tamu

iTrader: (36)

Take it to a dealer say I want PCM and TCM reflashed and it takes 20 minutes. The idiots shouldn't have a problem comprehending that no diagnostics required. Just a charge for labor to do the flash

Tig

iTrader: (2)

That's exactly what I asked for.
They brought out some sheet and said it was all good accept one updated file.