6.5 problem

[lugnut]

My brotherinlaws 95 3500 has the 6.5 with turbo and about 120000 miles on it. When your riding along it starts to miss and roll black smoke ( wont hardly get out of its own way when it does this )then it will just clear up and run good. It dosnt seam to mater if its hot or cold or how hard your driving it. It starts and stops doing this at randum. I'm thinking the injection pump or the computer controling the pump. What do yall think ?

 

[Diesel Dan]

Check turbo boost.
Might be the wastegate solenoid, that is a common problem.
That would be the quickest/cheapest fix. Solenoid is about $30 from the dealer.

That would account for the black smoke, but the miss???

 

[bigblock454]

I second the solinoid. Sometimes if you really pour the fuel to it with no boost it will stumble. Also check your air filter, it could be partially clogged causing decreased air flow, hence more likly to stumble.

 

[azblazor]

PMD#1, IP#2 (warranty still?)

 

[lugnut]

[ QUOTE ]
PMD#1, IP#2 (warranty still?)

[/ QUOTE ]

No warranty ( bought it used 2 or 3 years ago ) PMD # 1 IP#2 Whats that stand for ? /forums/images/graemlins/confused.gif

 

[bigblock454]

With the somewhat wide spread problems with the Electronic Injection Pumps on the 94+ GM upped the warranty on any 6.5 to 120K miles an 11 years. You said your mileage was about 120K, if slightly less you are stil covered.

This is important:

If you take your truck into the dealer for warranty work make sure you do the following:

1. Replace the fuel filter, cleaning 100% of the bowl housing of all foreign material. If they find one speck or anything in there they won't warranty it.
2. Make sure the lift pump is working properly.
3. They will do a fuel sample also, do you best to insure the tank is clean, no water or old fuel.

Are you seeing a DTC 35 or 36? They probably won't replace the Pump/FSD without any computer codes.

 

[lugnut]

Filters have been changed and check engine light has not came on.

 

[azblazor]

[ QUOTE ]
[ QUOTE ]
PMD#1, IP#2 (warranty still?)

[/ QUOTE ]

No warranty ( bought it used 2 or 3 years ago ) PMD # 1 IP#2 Whats that stand for ? /forums/images/graemlins/confused.gif

[/ QUOTE ]

PMD = pump soleniod driver (same as FSD fuel soleniod driver) it's a potted electronic package that allows the system to control the IP (Injection pump) as "fly by wire". It is mounted from the factory on the IP itself and suffers from heat damage and loose mounting (from heat cycling).

 

[lugnut]

OK now I get it. I saw that black box mounted to the pump but didnt know what it did. Does this driver also control the relay for the lift pump ?

 

[bigblock454]

On the 94 and 95 6.5s the Lift Pump is controlled by the Oil Pressure Sender. 96+ are controlled by the Computer.

 

[lugnut]

Ok so the oil presure switch controls the lift pump and the black magic box controls the inj pump. Thanks guys