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Lightyear
05-22-2009, 02:40
Having read the latest threads regarding problems with the PMD, I began to wonder. My '99 Burb has stumbled a few times once I got it home to ATL from Tampa. It is infrequent, but will completely die for a second or two, then pick back up. It has happened after sitting overnight. Start, idle, leave the driveway just fine. When I attempt to pull out onto a secondary raod, it'll stumble, then come back to life. This does not happen often, but enough that I want to get to the bottom before something breaks. Is this PMD syndrome? I haven't crawled around underneath yet to check things out. I've been in Taiwan for the last 2 weeks, but will use the beast as my DD again when I get home on Sunday. What should I be looking for? BTW, I have the Helm reprint manuals, so taking stuff apart is not out of the question.

Thanks, all!

Robyn
05-22-2009, 06:59
Could be.

Also I would be sure the lift pump is working correctly and the fuel filter is clean

A failing lift pump can display this symptom.

Open the water drain up front and direct it into a can. With the engine at idle there should be a nice stream of fuel running out and the engine should not die.

If no you fuel comes out and the engine dies, its the Lift pump or its electrical system.

PMD issues are normally a hot thing and occur after things warm up.

Hard hot starting and or stalling when driving etc are the hallmark of a failing PMD.

If there are no codes showing I would mount a new PMD with a #5 resistor installed on a cooler outside the engine bay.

DTECH makes a good one.

Check the fuel thing first and then look at the PMD.

Robyn

JohnC
05-22-2009, 09:29
Most PMD issues will not "pick back up" again. Once the PCM sees the PMD acting up it causes the engine to stall by dropping the fuel shutoff solenoid. A restart is required.

Your symptoms sound more like the lift pump is not running.