Decel to sudden stop causing stall

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Portmod7
Posts: 3
Joined: Sun Jan 01, 2023 10:44 am

Decel to sudden stop causing stall

Post by Portmod7 »

I put a 2004 4.3 out of a Silverado into a rock buggy with a TH350 behind it. Before I had enough motivation to figure it out myself, I sent the PCM off to have VATS deleted, fan parameters changed, eliminate unnecessary emissions equipment, etc. The motor is as it came out of the truck, and I believe the programmed engine running parameters are stock. I do not have the original BIN the factory programmed.

So, I've got my buggy together and running, but I wanted to change the fan settings without ripping the PCM out and sending it again. So, I've figured out how to get in there and do that now.

One other intermittent issue I have is when I am decelerating at slow speeds in 1st gear and low t-case range(4:1) and I suddenly step on the brake to stop for a rock, hole, or ledge, I sometimes get a stall. Firstly, is there anything that immediately jumps out that I could play with to help that? DFCO, Stall Saver, Idle overspeed, etc.?

I am providing a VSS signal to the PCM. A couple things I am questioning:

1) Transmission type is set to "0"(4L60E). That's correct for the truck it came out of, but why wouldn't it be set to "3"(non-electric automatic)?

2) Transmission Range Switch Type is set to "2"(P/N only switch), why wouldn't it be set to "0"(No range switch) since my buggy has nothing?

Thanks!
ATPCR
Posts: 26
Joined: Mon Feb 13, 2023 5:04 am

Re: Decel to sudden stop causing stall

Post by ATPCR »

@Portmod7 Those questions sound like to me that you have the equipment and can access the Bin and XDF file with Tunerpro. Is your TH350 an old style automatic with no electronic hook ups? I would make that change. Also, it doesn't sound like you need the park/neutral switch hooked up.
Why do you need the VSS? For the speedometer?
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