[alky]

Hi. My dad bought a 1994 chevy with a 6.5 It is having a problem that nobody can figure out. Can somebody please help. He took it to a shop. They charged him a lot of money and did no good at all. They siad the hermonic ballancer was broke. They put on a new one. They said they changed the sulinoid for the waste gate, they said they worked on the turbo. When you go to use the pickup it is hard to start. It now is harder to start than before. It takes it a little bit to fire off. When you drive it about 45 mph it surges. it always blows black smoke and has no power. He changed the oil, fuel filter, checked for cracks in the hoses going to the waste gate sulinoid. What else could we check to make this thing run. We are ready to pull our hair out. It has no power and surges. It also dies out when driving. It always starts back up but it does die out now and then. Please give some suggestions. I am sure it is not bad fuel...





Thanks: Alky

 

[kjanx]

usually, those problems are caused by the pmd, the pump mounted driver, the little black electronic box on the drivers side of the injector pump. if indeed, the whole pump is not on vacation.


i would get the pmd, disconnect the harness from the old pmd, just connect the new one to the harness, see if the performance changes.

 

[Turbine Doc]

Alky,


I'd go back and look to the last maintenance activity, what was 1st symptom that prompted the shop vist, how many miles on the Chevy.


If the truck wasn't acting that bad before it went into the shop belching black smoke I'd say they goofed it big time. What did they do to the turbo or waste gate, did they hook up the solenoid correctly after the swap. Was this a GM shop?


Go back to square one, and describe for us the before visit problem, then list in detail what they said they did for corrective action and why they did it. They should be able to give a direct answer when questioned; if they hedge the answer, then they were just shotgunning for a solution & part swapping in hope they found the right fix.


I'd also be looking for some money back cause it sure sounds like they had little clue of what they were doing.


Describe the current problem in a little better detail, define hard to start, always or just when cold, long cranks, multiple cranks, is glow system working, if equipped is lift pump coming on (BTW does the 94 have a lift pump I don't know for sure I think it does)


Once started how is the idle, after idle during driving what happens then, stumble only then settle out, or stumble then shutdown, stumble on accel or at cruise/any speed. If it dies, does it start back up easy or with difficulty. Lotta questions I know but also many possibilities the better the description the better advise we can give.


Do you have an auto zone or equivalent nearby that will read engine codes for free many part stores do that now, that many problems there should be a code or 2 set have them read and let us know what you come up with.Edited by: Turbine Doc

 

[16gaSxS]

on a '94 most people have a code reader..... a paper clip. Jumper first to ports on the right of the scanner hook up plug, key on no start and the SES light will flash the codes.


Lots black smoke no power hmmm waste gate turbo work hmmmm sounds like waste gate isn't working and you may not be getting boost. Surging could be PMD.


Pull codes and work them.

 

[Turbine Doc]

Doh,


I forgot about the paper clip trick and SES light count, it's been so long since I did that, it's not possible with OBDIIEdited by: Turbine Doc

 

[alky]

I am not sure what is going to happen with it now. The dealer ship is the ones who worked on the truck. They have been called and told they did no good for $ 1,100.00 The truck has no power, smokes heavy black all the time, hard to start all the time. It just don't want to fire when you try to start it. It acts like the glow plugs are working it just wont fire. Before they worked on it the truck started real nice and easy. Now after they worked on it its hard to start, it smokes all the time real bad, it surges at 45 mph. They claim they worked on the waste gate, turbo, replaced the hermonic ballencer which they claim was broken, and replaced the injector pump. All the work they did made the pickup run worse. So they have agreed to take it back and work on it at their own cost until it runs right. I appreciate everyones response and help with it. This is a real neat site and nice to be able to trouble shoot youre problems so you can tell if a mechanic or a shop is trying to blow smoke up youre butt.... Thanks again for the help....

 

[quantum mechanic]

I have a '94 L65. I had problems similiar to your's and it was the waste gate solenoid and a bad OPS to lift pump connection in the OPS.


I 've had a little time to reflect on this problem, and I can see that if it had been just one or the other this problem wouldn't have been so pronounced, but in unison the motor is prone to stall due to low fuel pressure to the injector pump(not to mention surge at higher speeds), and The WG/vac system failing somewhere causing long black exhaust trails and a general lack of power.

 

[Turbine Doc]

If they changed the IP I suspect from your description they screwed up the timing setting. Before paying another cent make sure whatever "new stuff" they find wrong with it, that they missed on 1st go round; is explained fully & why they need to fix it at your expense. What was original problem that led to the IP swap. I suspect you were having PMD problems, and the turbo problems they "fixed" were misinterpreted symptoms of incorrect time set of IP after replacement.


Remember the 6.5 is an "old engine" to most dealer techs, unless you have a dealer that has a old time 6.5 trained tech, make them give you a warm fuzzy of their suspicions and what the fix needs to be.


I don't post in the 6.2 or the 6.6 forums unless it's generic know how, they are that much different, also even in 6.5 world OBDI is very different from the OBDII I drive so I tend to limit my responses theree as well.