Are there different FSD's?

[Tom C.]

I've burned up my third remotely mounted FSD. I still have the original mounted on the pump which there is nothing wrong with. I just wanted a remotely mounted FSD after reading all the horror stories. Thought I would prevent a problem.

The new FSD seems to work well for a while then I get symptoms similar to a gasser misfiring. Plug back into the old pump mounted FSD and the truck runs fine. My remote is mounted behind the grill on a heat sink in front of all the other coolers so it gets all the air flow. It never feels even luke warm.

My injector pump was replaced at around 30,000 miles (before I owned the truck). I don't know the pump number but it has the green tag. It has never set a code. I now have about 60,000 mi on the truck.

Like I said, when I plug back into the old FSD the truck runs perfect. In fact it seems to run a little smoother and seems quieter at idle.

So anyway, I was wondering if maybe the older pumps and the brains that run them are different than the newer models and do I need to get a specific FSD for this pump.

Thanks for any insights

Tom C

[Hye]

Take a look at "Well She Finally Gave Up".

[tom.mcinerney]

Until a few months ago the sole available source of FSD/PMDs was Stanadyne. Many of their modules held up for 100K miles, many others failed at much less impressive intervals. Loose power transistor mounting nuts (poor quality control) was a chronic source of failure.
Last fall the Remarque Sol D was marketed. This is a vastly improved design [will create less heat, thus demand less heat-sinking, and impose less stress on the wiring harness]. There have been some teething difficulties attending its introduction, but the new device promises to do the job longer, and solve additional problems which resulted from the old Stanadyne design.
See:
http://forum.thedieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=007494

[gmctd]

Just for grins, pull the remote FSD and check each of the nuts on both transistors.

Back them off, run each one down to finger-tight, then add 1/4 turn more.

While you're at it, check the connector pins for oxidation\corrosion, cleaning if necessary.

The transistors also should not indicate any evidence of moisture intrusion, as they are at ignition potential when key is on.

GM carries a moisture-excluding electrical grease for external connectors, taillite\indicator bulbs, etc.

Good chance the problem is solved, once the above procedure has been accomplished, but you might also take the time to inspect\clean the other connectors in the IP harness.

These problems appear each year, as the climate turns cold and damp.