gradyc |
08-03-2011 02:26 AM |
ongoing coldstart problem
I will try to be as complete as possible about the problem. My boss has an 02 7.3 that had a bad cylinder and HPOP. About 1 1/2 years ago he bought a used engine from a junkyard. I did a compression test on the ground and found 2 cylinders with low compression that came up some with a wet test. I am a certified machinist and know that is the sign of ring problems but the junkyard insisted that it was valves and against my judgement the boss listened to the junkyard who told us to install it anyway. I have no way to scan it so we have had to rely on him taking it to shops with a scanner and he has spent more on diagnostics than it would have cost for an autoenginuity tester. Before I put the engine in I tested each glow plug on a battery and watched them heat up. After the install I hooked an ammeter between the battery and each glow plug through the harness to make sure there were no problems with the wires. I hooked the same ammeter between the glow plug relay and the harness to make sure that the relay was working and the rest of the harness was good. It has NEVER started right cold with the used engine. Even now with the night temps getting into the mid to upper 70s it still has to be plugged in. One shop insisted that is glow plugs so he bought the set of glow plugs, the undercover harness and valve cover gaskets. No change. The used engine is an e 99 model so I had to change the intake plenums, the turbo pedestal and turbo from the one out of the truck to the one I installed.When I installed the new glow plugs I did another compression test and 2 cylinders were about 370 and the rest were about 395. I have had a mechanical gauge in the HPO system and the cranking high pressure is as much as 1500 lbs. I don't remember now which set of injectors I put in it. I remember that the used engine had the ad injector in number 8 and the engine I took out didn't. The last time he took it to someone for diagnostics they told him it wouldn't complete the buzz test and the temp sensor is sending a temp signal of -50 degrees to the ecm. It sounds like it is only firing one injector until you crank it for 2 or 3 minutes. I know bad for the starter and batteries.. If it is plugged in it starts quickly but if it isn't it is like it is only firing on 1 cylinder. Where should I go from here?(besides maybe a red stick with a long fuse) Stock truck. No mods.
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I meant AE in number 8 instead of AD.
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