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Yukon6.2
12-10-2009, 09:23
Hi
Just finished changing the motor in my 97 3500 4x4 standard.Everything went good.The doner motor came from a 97 2500, i replaced the intake with the original non egr one.Both had the same inj pump.
I now have a hesitation/stumble when i decelerate.This happens when driving and when revving in neutral.So far there are no codes being thrown.
Anyone come across this before?
Thanks Thomas

Aftermath
11-24-2018, 10:32
Did you ever figure this problem out? Thanks

Yukon6.2
11-24-2018, 10:55
Hi Aftermath
This was a truck i got used,it had electrical gremlins.It wasn't used everyday just as required.After i changed the engine i went trough a couple of PMD's which were remote mounted,and were not Stanadyne units. Then i replace the ignition switch.Then one day i went to start it and it wouldn't fire,this was after driving it into my shop and shutting it off.By then i had accumulated everything to convert it to mechanical.I tried a few things and gave up and started cutting wires,now there is a computer living in the dash screaming away because it dosn't get any input and the truck does/did everything normal.Till the crank broke.
So i bought a Dmax tow truck,should have bought the Dodge Cummins truck,but i am a die hard GM guy.
Thomas

Aftermath
11-25-2018, 20:39
Hi Aftermath
This was a truck i got used,it had electrical gremlins.It wasn't used everyday just as required.After i changed the engine i went trough a couple of PMD's which were remote mounted,and were not Stanadyne units. Then i replace the ignition switch.Then one day i went to start it and it wouldn't fire,this was after driving it into my shop and shutting it off.By then i had accumulated everything to convert it to mechanical.I tried a few things and gave up and started cutting wires,now there is a computer living in the dash screaming away because it dosn't get any input and the truck does/did everything normal.Till the crank broke.
So i bought a Dmax tow truck,should have bought the Dodge Cummins truck,but i am a die hard GM guy.
Thomas

So I have a buddy that is experiencing a similar problem, issues on decelleration. Really nothing else I can find on this specific issue.

Yukon6.2
11-26-2018, 08:56
Try changing the PMD
I went through a couple of the aftermarket ones in that truck,they were remote mounted.

trbankii
12-05-2018, 08:47
By then i had accumulated everything to convert it to mechanical.I tried a few things and gave up and started cutting wires,now there is a computer living in the dash screaming away because it dosn't get any input and the truck does/did everything normal.

You mention it was a '97 4x4 standard - which I assumes means manual transmission? I'm curious about what else the computer controls (or tries to)? I'm thinking about MFI on my '94 and would swap in a manual at the same time, but then got to wondering what else I'd have to tinker with. ABS? Instrument cluster? Other things?

Yukon6.2
12-05-2018, 10:10
There was nothing else effected by the swap.
My ABS was already disabled,all guages worked fine.
I lost the high idle through the computer,just used a manual high idle.

JohnC
12-05-2018, 11:39
Just out of curiosity, what resistor do you have on the PMD? I recall when I had a high number (don't remember if it was 9 or "13") on a pump that called for a 4, I had issues with surging just off of idle. Seems like when it transitioned from "closed throttle" to the pedal reading it gave too much fuel. I theorized it's because fuel rate at idle is based on RPM whereas off idle it's calculated, and the high number forced it to calculate a higher rate.

ronniejoe
12-05-2018, 12:03
I tested the SOL-D FSD for TDP a long time ago. When descending a grade with the cruise set and the BD TorqLoc engaged, that thing would cause the engine and truck to surge and buck violently until you turned the cruise off. I dug a little deeper and realized that the engine would hunt or surge when descending a grade with cruise off as well, it just wasn't very noticeable. The SOL-D apparently had troubles with metering fuel rate under no load situations. In fact, my negative review probably sunk that whole project.

This never happened with a Stanadyne FSD. I would look at the FSD as a potential culprit.

trbankii
12-05-2018, 17:32
There was nothing else effected by the swap.
My ABS was already disabled,all guages worked fine.
I lost the high idle through the computer,just used a manual high idle.

Thank you for the input. I can't say that losing ABS would necessarily be a bad thing as far as I'm concerned.

Yukon6.2
12-07-2018, 10:36
I prefer the ABS delete option myself...
One of the joys of living here,no inspections to worry about.