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TTM
05-19-2011, 08:28
Hey guys, really quick question. My 94 has been running like a top for years, regular maintainance batteries good, clean terminals, lift pump strong( hear it growl for a couple of seconds after I shut down the truck) , fuel filter replaced,OPS never replaced, IP replaced under the Chevy recall 8 years back, no modifications to anything, but like I said running good every day.

I replaced the fsd with a Kennedy remote mount system about 4 years ago and wondering can the fsd get weak? What I have been noticing is when I start the truck cold it starts and idles fine, but when I drive at about 1200-1700 RPM it starts to flutter, not cut out but loose power every so slightly and then after that good at any rpm. Now I should mention that the SES light came on awhile back and I took it down to the dealer and they indicated it was "pulse width error to low" so I kinda knew that somethng wasn't right but have been driving without a problem. Could that be the problem? is the fsd getting weak to the point were it won't deliver fuel at a certain RPM range.

Just some thoughts from you guys would be greatly appreciated.

More Power
05-19-2011, 10:24
Do you have an original black Stanadyne FSD/PMD module? If so, many of them have a repeat problem at some point...

TTM
05-19-2011, 11:41
Yes I do. There is Stanadyne orignal that I disconnected from the IP to do the remote; and the one that I got from Kennedy Diesel ( remote mount) would be a Stanadyne FSD/PMD as well.

I have the SOL_D mounted but I quit using that after the 9v issues and have never used it in years.

Does that sound like the problem?
What is the repeat problem?

Thanks.

TTM
05-19-2011, 11:51
I just visited the Kennedy site and there is a "GREY" FSD/PMD model? Is that what you were getting at. I the grey model a newer version? Is the black model obsolete?

racer55
05-22-2011, 15:00
The grey PMD is the new stanadyne update model.
the black stanadyne PMD's are fine when they are working but some will fail by cause a no hot start,stalling and eventual no start.

I would inspect the extension cable at both ends and around the resistor for any corrosion that may have developed over time,a good electrical contact cleaner may solve your trouble?

You may also have the beginning's of an IP that is on its way out-hopefully not.

Robyn
05-22-2011, 19:03
The pulse width error could well be caused by a PMD thats failing.

Many times the PMD fails with a no start or the engine just dies ubruptly.

The other failure of a PMD is the FULL throttle wide loose until the overspeed trip (computer) shuts the thing down at redline RPM.

I will not buy or use a Gray Stanadyne PMD

Standyne screwed us around for years with the same old failure prone JUNK

The DTECH PMD is a good choice in my opinion.

I have not had any troubles with them at all.

The pulse with error can happen under a condition where the rig is rolling along at road speed and the PMD dies for a short time and the tranny stays hooked up. The ECM does not see the expected input back from the fuel solenoid in the IP so the pulse width error code is set.

The short pulse width is the result of the PMD failure. If the PMD had failed at a lower RPM, the result would likley have been a stall.

Get a DTECH PMD and hook it up with the original cable setup.

Just make sure that the original ground wire from the harness is fastened to the IP as it was originally from the factory.

If a new PMD does not correct the troubles, then likely the issue is with the IP.

Try a PMD first.

I hate to be such an ASS about the Stanadyne units, but these clowns had many years to come up with a good reliable fix and they did not.

It was not until Dtech came on the market did they finally come out with a replacement.

Just a slap in the face to all the owners of the GM 6.5 diesels.

Another good plan is to always carry a Known good spare in the glove box.

If your Remote mounted driver is tough to get to under a late nighter in the dark/rain make it so you can plug a spare onto the main harness under the hood. It will get you home at least.

Just have the spare mounted on a heat sink is all.

Even a top hat manifold mount is good in a pinch.

Good luck with the gremlin

Missy

More Power
05-23-2011, 10:00
Yes I do. There is Stanadyne orignal that I disconnected from the IP to do the remote; and the one that I got from Kennedy Diesel ( remote mount) would be a Stanadyne FSD/PMD as well.

I have the SOL_D mounted but I quit using that after the 9v issues and have never used it in years.

Does that sound like the problem?
What is the repeat problem?

Thanks.

Since you already have the SOL-D, try it, as a way to further your troubleshooting. Other than the low voltage issue and a AM radio interference problem, they have worked OK.

Jim

TTM
05-25-2011, 10:29
Thanks guys for your suggestions, Jim, I hooked up the sol-d and the truck ran fine and NO SES light no flutter at low rps BUT this was when it was warm. So I think that I will use that as my back up. It's a FSD/PMD issue.

Racer I looked at the connectors and they were good.

Missy, you suggest the D-Tech eh? it is cheaper up here than the Stanadyne unit and from what you indicated it plug right into my Kennedy cables and mount on the remote behind the batttery? The Grey Stanadyne has to be made netrual as indicated on the Kennedy website.

Okay, if the D-tech can mount with out any extra brackets that might be the way to go, if the modification to the Stanadyne isn't to painfull that is a option to. Comes down to cost.

I have soaked probably 800 bucks CDN into these PMD's and it's getting a bit much for a 94. Not saying the old girl doesn't deserve it but she's all I got. I do peek at the new chev duramax's more these days though......

More Power
05-25-2011, 11:00
Thanks guys for your suggestions, Jim, I hooked up the sol-d and the truck ran fine and NO SES light no flutter at low rps BUT this was when it was warm. So I think that I will use that as my back up. It's a FSD/PMD issue.

That's progress.... The D-Tech has been on the market now for 5-6 years, and I've only heard of one failure - as opposed to thousands of the black Stanadyne versions... The new gray Stanadyne module may be OK, but a lot of people are a little PO'd that it took Stanadyne 15 years to reinvent their own epic failure. As a bit of trivia, GM was also PO'd about all this, and they began stocking, selling, installing the D-Tech module at GM dealerships.

D-Tech is what I recommend... ;)

Jim

racer55
05-27-2011, 11:51
That's progress.... The D-Tech has been on the market now for 5-6 years, and I've only heard of one failure - as opposed to thousands of the black Stanadyne versions... The new gray Stanadyne module may be OK, but a lot of people are a little PO'd that it took Stanadyne 15 years to reinvent their own epic failure. As a bit of trivia, GM was also PO'd about all this, and they began stocking, selling, installing the D-Tech module at GM dealerships.

D-Tech is what I recommend... ;)

Jim
The flight systems PMDs have a bad batch run and they are aware of the serial #s involved.
I have no idea if they recalled that batch from the vendors who have stock or are just replacing them as they fail.
I am very surprised that you are only aware of 1 failure.

Burning Oil
05-29-2011, 05:21
The Dtech/FS PMD has had many more failures lately than the grey "S".
They were causing a run away condition. The problem is now fixed though.
For awhile I quit selling them because of it. I've had one Grey "S" PMD fail.

Just my experience for what its worth.

TTM
05-30-2011, 11:46
Well went with the D-Tech ($319.00 CDN) installed it right up to the remote mount heatsink behind the drivers side battery pretty simple. The old Stanadyne unit had a bit of rust on it and the little pads were all soft and barely protecting the units resistors??

Anyway, truck starts 1000 times better clean and sharp, and no fluttering at low rpm's after warm up and accelerating to 70km/h (40mph). The ses light comes rarely but it think it could be a hard code set and I need to clear it. Looks like I got the problem.

That it, reading the last posts I HOPE HOPE that if there is a recalls or problems that the manufacture has dealt with them. I can't afford or have the time anymore for this and what I feel should have been a easy fix 15 years ago.

Thanks guys for all your help.

Burning Oil
05-30-2011, 11:58
Well went with the D-Tech ($319.00 CDN) installed it right up to the remote mount heatsink behind the drivers side battery pretty simple. The old Stanadyne unit had a bit of rust on it and the little pads were all soft and barely protecting the units resistors??

Anyway, truck starts 1000 times better clean and sharp, and no fluttering at low rpm's after warm up and accelerating to 70km/h (40mph). The ses light comes rarely but it think it could be a hard code set and I need to clear it. Looks like I got the problem.

That it, reading the last posts I HOPE HOPE that if there is a recalls or problems that the manufacture has dealt with them. I can't afford or have the time anymore for this and what I feel should have been a easy fix 15 years ago.

Thanks guys for all your help.

Now you just need one more as a back up :eek:
I sell the Dtech/FS PMD for $175 or $205 with #9 resistor.