Greetings.

I took my 2004.5 CTD 4x4 QC 6spd in for service because it started to miss at startup after sitting over night with lots of white smoke coming out the exhaust. It was low on power while pulling an 8k load and putting out lots of smoke when pulling grades. I figured it would be an injecter, but the dealer called and said it was a lift pump. I'm confused on how a lift pump can cause a problem at idle? At this point the truck is totally stock.

 

What method did they use to determine it was bad......fuel pressure or volume ? I'm by far no expert, but I'd suspect you have one or more injectors causing your problem more so than a lift pump.
Greg

 

I have no idea what method they used to determine the failure. I talked to the service writer, not the diesel technician. Another thing was that fuel economy had dropped some while towing. Again how would a lift pump cause this? I'll let the dealer replace the lift pump, but after that if the engine is still running like crap I hope they start looking at the injectors.

 

Keep on them RaminTexas.

You're on the right track. There have been lots of threads on this.

 

Well I got the truck back after about a week. Apparently lift pumps were on back order so I had to wait for one to come in. They replaced the lift pump but the truck was still acting up. So I took it back to the dealer on Tuesday so it would sit overnight for them to see the problem. Called them today and they are still looking at it. Apparently STAR is asking for a whole bunch of tests and printouts. The good thing is that the service writer agrees that there is definately something wrong - he could have said the old line of BS that all diesels run like this on startup." I just hope I don't get the DC company line of too much idle time. The truck has a build date 0f 3/04 and I bought it in late November. Since then I have put over 15000 miles on it and half of that is towing a 10k load. If there was any excess idle time it happened on the dealer lot. The funny thing is that the truck ran great for the first 12k miles. I've used PS & Stanadyne PF since it was new and I changed the fuel and air filters right after this problem started

Reggie

 

turn your key on and off 3 times...any codes pop up in the odometer?

 

I honestly did not check. The first time I took it in the dealer said there was a code for low lift pump voltage, that's why it was replaced. The check engine light never came on for this problem. I think it is an injector problem, but I have to convince the dealer/technician and they have to get STAR to approve it. Kinda stupid but it's what we have to deal with.

 

Ask them to do a cylinder kill test(shuts off injectors one at a time) while its missing...the cly that doesnt change the miss as much is the injector at fault..do you have a longer than normal crank time ? Plus get them to check inj pump pressure at full load..should be upwards of 20000psi + , if lower , it will prob be the pressure relief valve opening at a lower pressure causing low power.

 

I did ask them to do an injector kill test when I dropped the truck off. I just got off the phone with the service writer and he said that they are going to replace one injector - but there are none to be found on the west where I currently reside. So best case will be mid next week.