Will a bad PMD cause hard starts? This is on my 94.

I do not have the common stalling problem where driving down the road and it just dies like you shut the key off, it has never done that. It has a few times died while driving when removing my foot from the gas peddle quickly though, like slowing to make a turn or stop sign.

I have replaced injectors, glow plugs, starter, battery cables, batteries, all fuel lines on the engine, O-rings in the filter housing, lift pump and cleaned all the grounds I could find.

It cranks worse first thing in the morning, you can hold the gas peddle down and it will fire alot quicker almost normal, but I dont like to hear a diesel rev like that when its cold. It cranks better the rest of the day but it doesn't just fire off like my older ones do.

I was thinking about trying a new PMD, but dont know if thats my problem. Maybe my injector pump is wore out or maybe it is something else.

I thought I read somewhere that GM came out with an updated EPROM for the 94 models, for slow cranking, but I cant find the article again. Does anyone know what P/N that chip was for an vin "F" automatic truck.

Thanks guys,

I didn't see OPS in your list of things. It's easy and cheap to replace and would cause the lift pump to shut down causing hard starts.

Midnite, i'd really like to see some pictures of the engine and guage setup in your play rig :) looks pretty cool

Ireland,
Good catch, the OPS quit, so I tied into the fuel pump wire with a relay triggered by the ignition switch, my 93 is the same way. I no thats not as safe as what GM had planned, but I'm not to worried with diesel. My 92 still has a functioning OPS so it controls a relay for my lift pump. The lift pumps seam to last many times longer with a good supply of voltage.

The 94 does pass the lift pump test with the engine running, it seams to have real good flow. I also thought it was a fuel leak down or air causing the harder first start of the day. Thats why I replaced all the hoses and O-rings on the engine, but I cant find any leaks and no signs of air in the fuel system and I dont smell any fuel. After the engine is warm it still seams to crank to long before it fires, my dads 50 year old 2 cylinder John Deeres diesels fire off quicker than this thing hot or cold.

Matt,
I've been meaning to start a thread on my truck, I just haven't had time, this is the first 40 hour week and Saturday off since September I've had, been working 60-84 hours at an Army Depot on HMMWV's.

Speaking of gauges I'm fixing to go install a line pressure gauge on my 93's transmission so maybe I can figure out what is wrong with it, torque converter is slipping. Other than that its a fun truck to drive. I'll see if I can get some pics up.

Thanks guys,