RE: New TB & PCM/WOT Shift Point Problems

From: Ronald Wong (ron-wong@home.com)
Date: Sun May 20 2001 - 22:28:44 EDT


I wouldn't worry about the revving too much if it's set for SC. That means
the timing should be retarding at the top of the power curve to keep
detonation from occurring.

Ron
00 PB SLT QC 4X2 5.9 46RE 3.92 LSD
For modifications see my DML Profile (URL follows)
http://www.twistedbits.net/WWWProfile/dakota/Kw9pV1EkFeOYY

-----Original Message-----
From: owner-dakota-truck@buffnet.net
[mailto:owner-dakota-truck@buffnet.net]On Behalf Of Shawn Bowen
Sent: Sunday, May 20, 2001 4:55 PM
To: dakota-truck@buffnet.net
Subject: DML: New TB & PCM/WOT Shift Point Problems

I just put on both a Flow Metrics 50mm TB and had my PCM reflashed by Leach.
Well, I know they bumped the Rev limiter made other changes to the PCM,
unfortunately I need to call them to give me the exact numbers. My problem
is this, since replacing the TB the throttle seems sticky at times. The
shifting at half throttle kicks ass but at WOT it almost feels like I'm
bumping the Rev limiter before shifting, this is right around 5k RPM's. I'm
hesitant to really get on it because I had the PCM setup for a PowerDyne
Supercharger, but it isn't here yet. At WOT it sort of feels like the fuel
is cutting out at around 5K, if I let up a little it will shift and then
pull HARD until around 5K again. I believe the Rev limiter was set to 6500
RPM's so this concerns me.
        I made several changes this weekend. Put the new TB on, replaced the Fan
Clutch with a Black Magic electric, and dropped the new PCM in. I drove
about 100 miles at varying speeds on both the highway and in the city and
then in traffic (checking the Fan out in Atlanta traffic;-)). The truck
pulls a LOT harder when I get on the gas but at WOT the shifting scares me
so I back off.
        I know the transmition has linkage on the TB and was wondering if that
could be the source of the sticking issues. I am also wondering if maybe
I'm getting lean at WOT and starving of fuel, the reason I'm curious is that
the PCM was setup for the PowerDyne with a new fuel pump. On two occasions
the MIL light flashed when this occurred at WOT, only for a split second.
Currently, while waiting on the Supercharger I'm still using the stock
airbox and filter, that's why I'm wondering about whether I'm running lean
and that's causing the engine to cut out.

Currently the truck is setup as follows:
5.2L 318
180 T-Stat
Black Magic Electric Fan (no fan clutch)
Flow Metrics 50mm Throttle Body
Gibson Dual Cat Back
Stock Airbox (until either the SC or the K&N FIPK I ordered shows up)
Leach Custom PCM setup for the SC
93 Octane Fuel

Any help or advice would be appreciated!

Shawn
98 5.2L 4x4 CC



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