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View Full Version : HELP PLEASE 5 speed throttle control



thepolecat
06-28-2005, 07:26 PM
Hey guys, I have a 97 GMC 1500 4x4 with 305 vortec and manual transmission. I have had it for several years now, and have always been annoyed at how it seems the computer controls my throttle when shifting. If sitting in neutral, it idles perfectly, but if you mash the gas and let off, it will hold itself at the high rpm for a couple of seconds or so and then fall back to an idle. Also, if you shift from one gear to another, it will hold itself at high throttle after you clutch, and dispite letting off the gas pedal. Also, when going down a hill, you can't let off the gas and rely on the engine for brakeing, because the truck holds itself at the higher rpm still. (although sometimes at low speeds it will engine brake, but only for a few seconds).

It has always done this since I bought it used years and years ago, and is no porblem other than an annoyance. Some people with similar trucks said they had the same thing, but that it was possible to program it to not do it. A GM tech I talked to at the local dealership said it was part of some emmissions control and was not possible to turn off. Does anybody on here have the same thing or know of a way to get it to act like a normal 5 speed should?

Thanks for any help.

Jarrod

bobzilla75
06-29-2005, 07:40 AM
That is normal, unfortunately. Most emissions are released between the shifts, as the engine slow itself. That's why all he manufacturers make their manuals "hang" between shifts.

Good news: You can have your PCM custom tuned to eliminate this.

thepolecat
06-29-2005, 09:47 AM
Most emissions are released between the shifts, as the engine slow itself. That's why all he manufacturers make their manuals "hang" between shifts.


i sorta expected this, but im just glad to hear from sombody on here that i can get it programmed out. thanks!

75-K5
06-29-2005, 11:00 PM
Why don't you like it? For me it seems that it keeps the RPM's in the right range for the shifter to just slide in the next gear easily, at least when upshifting. It helps eliminate some of the inevitable lurch you get with the 5 speed (or maybe I just suck at driving a manual)