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Thread Title:

poor starts,rough idle when cold,blue smoke

Created On Thursday May 27, 2004 23:36

pumper30

Posts: 3
Joined: May 2004

Thursday May 27, 2004 23:36

If anyone can help me, I'm at my WITS end.

I have a 1995, Chev 6.5 T Diesel. It all started when my dealer replaced the driver. I was getting poor starts, a rough idle for a few minutes, and blue smoke to accompany the rough idle. I replaced the pump, and that didn't help. The dealer replaced ANOTHER pump and sent the injectors to a diesel shop and got them cleaned and calibrated. They checked the glow plugs, all were OK. Yet, when I start the truck after sitting for as little as a few hours, I get a VERY rough idle and lots of blue smoke for a few minutes. When I start driving, the engine surges and misses and intermittently puffs blue smoke. I've been told by my dealer that this is the way they are. But yet, it was NOT like this when I bought it. The latest thing that I've done is replaced the ECM. That did not help.

ANY IDEAS???

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ROALDERIC

Posts: 11
Joined: May 2004

Saturday May 29, 2004 09:25

It sounds like you have air in the system. The air is most likely coming from the suction side of the fuel system between the fuel tank and the pump. Hard starting, smoke and rough idle are classic signs of aerated fuel. If you picture the fuel system, you will have a suction side and a pressure side. Anything before the fuel pump is suction conversely, anything after the pump is pressure and will create an external leak. Any leaks on the suction side will not be visible, since they are sucking air into the system, not pushing fuel out. The longer the truck sits, the air will enter the lines and drain back to the fuel tank. That is why it is harder to start - it is sucking the fuel from the tank up to the engine. That fuel will be full of air and will not allow the pump or injectors to work properly.

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pumper30

Posts: 3
Joined: May 2004

Saturday May 29, 2004 10:52
I have checked the turbo and found oil coming from the valve cover.Disconnected line from intake boot of turbo and pluged off the hole.Will try this for a couple off days, will also disconnect line from turbo to intake and look for oil As for the fuel proplem any ideas how to find the leak on the suction side?????

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pumper30

Posts: 3
Joined: May 2004

Tuesday June 08, 2004 09:36
I pulled the intake off and I don't now how it was breathing it was so plugged with carbon and oil.Ifind that I have vacumn at the egr valve on a cold motor should this be ??