Oh Please help!!
I read this last post, and this is what I am experiencing. When cold it has a problem starting.
I completly agree with you on the injectors not opening and what the dealers are telling me is that I have bad injectors....
Please let me know if you found out anything more on this possible leak, or if anyone else can help out.
Things I have tested:
using AutoEnginuity Scan tool I have
- Commanded 160 Mpa at IDLE gets 85 -95 Mpa, however a litte more throttle will get it up to 160 mpa ( But this should not be done I am told for a proper test) So My NEW pump that the dealer replaced only gets to 85 - 95 Mpa, however this pump that was installed was RUSTY, excpet for the FRP and the Gearator pump on the back of the High pressure pump. I cannot figure out why these two parts are shiny new and the main high pressure part of the pump is rusty. Manufacture date was November 2008, and installed end of Aug 2010?, 2 year old pump? I ordered a cp3 pump from the same dealer just to get pictures, the manufacture date was only 10 month prior to when I got it. The one I ordered had a sticker that said Product of Czeck Republic. Where the one the dealer changed out had a sticker that Said Made in USA. ( Part numbers are correct on this one) I STRONLGY beleive that they put in a used pump, and then changed over the FRP and Gear pump to get it to work. 3 days after I got the truck back, the same problem started, Ie Hard starts when a bit cooler. Less then 10 Dec Cel.
other then only getting about 90 Mpa, I checked the balance rates for each injector, I only did at idle, but they were anywhere from -2 to +2, on occasion I seen some change to -3 but very brief. I will check when in drive later.
I also commanded each injector off seperatley. The RPM fluctuated the same for each one, about 20 - 30 Rpm up and down. All pretty much the same, none made a drastic difference.
I do have the GM books on this truck, and have read up on testing return rates, high pressure side tests. Problem is I dont have the proper tools to do this. Im sure I can get a few graduated cylinders and do these test, but is it worth testing the return rates if the balance rates are what they are?
One last Item I forgot to mention is that even in my garage when temp is about 5 - 10 Deg Cel, I had the scan tool connected, while cranking at about 140-150 rpm, the rail pressure was only getting up to 1000 - 1150psi
When engine was warm, I disconnected the injectors ( all 8 ) and cracked it over ( yup set alot of codes) but I did this to see what the rail pressure was when cranking at 150 rpm, i was getting 10 or 11 Mpa ( Sorry, I forgot to change units on scan tool) Again this is with a warm engine. Will try in morning when cools down.
The fuel primer takes ussualy takes between 8 - 15 pumps if it is left for a while, ie a few days, BUT when opening the fuel port at the front right where the pressure gauge goes, I see fuel come out on the first pump, with no air.
At the end of the day, I think they put in a used pump, and it didnt last as long as they wanted. But considering that what they did was criminal fraud, I want to be sure when I in there that I am 100% certain they know that I have the info to back myself up with the condition of the pump and its ratings.
It was so rusty, I though it was the original, they are so lucky the pump wasnt from 2001, since my truck was a 2002...
Any insight would be helpful. I am going to need the truck every day for work in a month and want this problem to go away.
Additionally FRP term I used may not be right, I am reffering to the selenoid on the high pressure pump (Regulator?)
Also: When monitoring desired and actual rail pressure they are the same, and fluctuate slightly from each other as the throttle is pressed.
When started engine runs smooth, fuel economy is not the best, 430 Km on a tank, pulling traler and bobcat ( total unit weight truck and equipment is 12000KG, and city driving)
Truck has 150000 Km's on it, Injectors replaced at 65000Km's and 110000 Km's, first time may have only been bad ones, not sure, all 8 replaced the second time, yup, Gm's finest product. According to this km/injector ratio... or is it Injector/Km ratio? yah.. enough said.
p.s. This all started August of 2010. Literally no problems, just parked at home, went to go to work the next morning, truck wont start.
Now what I notice while cranking is white smoke from tail pipe, large poof when finnaly gets running. Glow plugs new, tested, glow plug relay tested, feedback working, Intake air heater working, Fuel warmer working, new filter, no leaks at filter base, tested pressure after priming goes from 10 psi to 2 psi after 5 minutes or so.
I hear Randy Marion Chev. of Mooresville has a large med-duty diesel service dept. They are not too far from you. Might give them a try if you haven't already. City Chev. of Charlotte is supposed to be good also. Good luck man!
