3b spluttering, coughing on cold starts/altitude

[joshoisasleep]

Title says it all. My 3b has recently (last few weeks) started spluttering, coughing, and sometimes even dying once or twice when started cold at altitude. It didn't used to do this. It appears to have been getting slowly worse. The lower I am/higher the ambient air temperature, the less the symptoms. At sea level in warm conditions there is still a VERY faint hint of the revving.

The behaviour is kind of 'wave' like. It goes vrrmm VRRMM vrrmm VRRMMM vvrrrrm VVRM mrermenmtw cough VRRM splutter vrrrm VRRRM until it starts to warm up.

I'll post a video tomorrow.

Thoughts? Fuel? Air filter's good. Injectors recently done. New turbo install didn't seem to make a difference.

 

[PressOn]

The wave description sounds like a fuel issue.... my guess is air in the line at the injector(s)? There are some good posts on how to bleed the injectors after the fuel line is opened.

Good luck and let us know what you find.

Jeff

 

[canucksafari]

I agree with the air in the fuel line. There have been lots of posts here about this. The primer pump has often been a culprit as has been the seal or casing of the fuel filter assembly. All you need is a little crack. Tell tale sign would be a small fuel leak usually not dripping wet - just damp. This is not always the case. Sometimes a crack will let air in but fuel will not go out. From the tank to your IP, the fuel pressure is low, so it is unleikely you will see streams of diesel shooting out. From the IP to the injectors the fuel pressure is very high. Any leak here would usually be obvious.

 

[cruiser_guy]

First check the glow plugs as this is a starting issue. After that if it is something that persists even when warm it could be the injection pump diapragm going bad.

 

[joshoisasleep]

I happen to know that my primer pump is busted, so that may be the answer...

 

[cruiser_guy]

I happen to know that my primer pump is busted, so that may be the answer...

That's always a good start! Fix the known faults and see if it all works right!

 

[joshoisasleep]

It'd been like that I'd totally forgot about it until mentioned above!