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skorgen
12-27-2006, 16:50
I have an 03 Chev 2500 HD with 85k km. For the past month or so starting is hard espeecially in the cold - will often turn over many times before catching. Twice it wouldn't go at all and I've had it towed to the dealer and many dollars later I've got a new battery, new bleeding screw, new conductor for one bank of glow plugs and exactly the same problem. Seems to turn over OK. Last winter it started perfectly. Had the injectors replaced during the first year of use by the previous owner. Frustrated but love the truck. Could this be an injector problem? Dealer did fuel vaccuum test and fuel pressure control test and all OK. Starts perfectly immediately after first start.

Any ideas??

Bob

Mark Rinker
12-27-2006, 19:48
Has the intake air heating element been tested?

skorgen
12-28-2006, 13:54
That hasn't been looked at to my knowledge. Will look into it. Thanks.

Bob

DmaxMaverick
12-28-2006, 14:25
How cold is cold? The heater element won't have much of an effect on cold starting unless it gets really cold, like well below freezing. It will help clear up smoke on startup, and smooth out the idle some, but should not cause long cranking starts.

Other possibilities....

Air leak. Are you able to bleed air from the filter housing when it doesn't start?

Excessive fuel tank vacuum. A malfuctioning (or wrong) fuel cap can prevent the relief of vacuum, making it much more difficult for the pump to develop pressure. This condition is exaggerated during winter. The fuel gets hot from running, and cold ambient temps cause much contraction of the fuel and air in the tank as it cools.

Injectors. Injector issues have caused hard starting. Many have reported much quicker starts after injector replacement. High return rates will also cause hard starting, but there should be some indication of a DTC. Keep a close watch on the oil level. If you have injector problems, increased oil level (fuel in the oil) is very possible.

Fuel pump or FRP regulator. If the fuel pump is weak, or the rail pressure regulator is malfunctioning, it will cause hard starts. There should be an associated DTC.

Glow plugs. Verify all plugs are good (easy test with a test light or VOM), and are getting juice. The relay and fuse is under the hood. Is this a CA or federal emmissions truck? It makes a difference as to the diagnostics and operation. The CA trucks are much easier to diagnose, as each plug has its own circuit, and reports current usage of each plug to the PCM.

mark45678
12-31-2006, 16:49
time for a trip to the dealer , every duramax truck I have owned starts in 3 seconds with out being pluged in over night. -15*F and you want to have the block heater on after that. sounds like maybe a bad temp sensor that is causeing other problems.

skorgen
01-04-2007, 10:25
Thanks for the info. The truck is back at the dealer today and the first thing they did was to replace the conductor connecting the right bank of glow plugs (corroded but not broken) - big job labour wise. I find it hard to believe that's the problem as I have a recently replaced (broken) left side connector and presumably a fully fuctioning bank of plugs on that side.

Jus got a call from the dealer after expressing my scepticism as to the corroded connector. Apparently on further testing there is some indication of an injector problem - wants to keep the truck for another day. Hopefully I'll soon have a functioning truck:)

Bob

More Power
01-04-2007, 21:22
Loosen the fuel tank cap when you park the truck after running it. Dmaxmav might be on the right path. Excessive vacuum in the tank might be a contributor to the hard to start issue. If loosening the tank cap helps, I'd replace it. The cap is supposed to vent at 2 psi positive pressure and at 2" vacuum.

Does any air accumulate in the fuel filter between driving sessions, or after sitting overnight?

Jim

skorgen
01-05-2007, 13:10
There is no air in the fuel filter at the time of a no/hard start. I will try the fuel filler on the next cold day.

Got the truck back from the dealer today with the right glow plug conducting strip replaced. I now have to wait for thetemperature to drop. The problem was noticeable in the -5 to -10 C range and it's a balmy 2 or so today. Most likely early next week will be cold again here in Newfoundland.

skorgen
01-18-2007, 10:29
Turns out the heater in the fuel filter assembly is not working! They have ordered the part (the full fuel filter assembly) which is over $1000.00 CAD. At first I was told it wasn't covered under the warranty but when I showed them the warranty book (it says the fuel filter assembly is covered for 5 years/160K Km) they agreed to cover it!

Hoping for a good cold start.

ktingey
01-29-2007, 10:08
Bob:

I have the same truck ( 03, 80K miles) as you and it sounds like the same problems. I've taken the truck to 3 different dealers. The first wanted to replace all the injectors at a price of $5,000. The only thing the other dealer stated was "this truck came out of Canada" and they wouldn't give me any reason why that is different. I live here in Utah and everytime the temp drops below 40 to 35 degrees F, it won't start. The third dealer did a thorough check and stated everything looks good. Their only suggestion was to try putting in better fuel and an additive of which I was already putting in. Well, last weekend I was up in the mountains on a scout activity. The temp was around 0 to 10 degrees and the the truck would not start. Everyone else that had a diesel, they all started fine.

I'm back to the drawing board on this one also. Did you try loosening the fuel cap yet? I think I will try that one also. I'm sure interested in what you find on your truck.

Kim

skorgen
01-31-2007, 07:03
Indeed the problem was the heater in the fuel filter assembly. It sounds like at first it appeared to be OK but on further testing a fault was found ("traced fault to heater thermistor open internally"). The fuel heater turns on with the glow plugs and I guess rectifies fuel gelling that can occur. The heater apparently can be taken out of the fuel filter assembly but the entire assembly itself was the part they had to order. In any case, everything they did before that made no difference at all and with the new part the truck starts perfectly well even on a day like today (-8 Celcius). I like my truck again.:) Hope this is helpful.

ktingey
01-31-2007, 09:09
Thanks for the input. I just took the truck to the dealer last night and I gave them a print out of all that you and the other have said. It was interesting to hear them say "wow, we didn't think about the heating element, you've really done your homework". I'm very courious to see what happens. They are going to look into the heating element itself. The dealer said it does NOT create a code when it goes out. I'll let you know what happens. I'm very hopeful. It would be nice to be able to trust the darn thing again. Our tempuratures here in Utah have been down around 10 to 15 degrees F during the night.

skorgen
03-28-2007, 17:15
Hopefully you got your problem solved. For interest sake, my cold starting problem recurred a week or so ago and as I speak the truck is at the dealer getting the injectors replaced (according to the service records the previous owner had them replaced also at 30 odd K Km). Hopefully this will do it.

Duramaster
03-28-2007, 21:23
So "KTINGEY" did the dealer say they would not warranty the injectors because the truck is from CANADA?????:confused: :confused: :confused: