'01 Dmax getting harder to start
'01 K2500HD w/6.6 Dmax. 115,000 miles. original injectors.
It seems my Dmax is getting harder to start. Started noticing this in late Dec last year ('07). Engine used to start in 3 seconds or so even if fairly cold outside; if warm (or if engine was plugged in over night), 2-3 seconds cranking before it would start.
Now it appears to take up to 6 seconds of cranking for the engine to start if the engine has sat for several hours (even with the engine plugged in over night or, after the glow plugs have cycled). If the engine has been run for a while and shut off for less than an hour, 3-4 seconds of cranking is needed. I did have a problem late December where the engine appeared to start normally after about 2-3 seconds of cranking (after sitting for ~8 hours @ mid 20s temperature), but quit after running ~15 seconds. Had to crank the engine nearly 30 seconds before the engine was able to be restarted.
No SES indicator appears and the local dealer tech saw no codes set in the ECM. I changed the fuel filter 1st week of Jan '08 with no improvement in starting. Not seeing any signs of leakage from the top side (filter, fuel rail, injector lines, etc). I'm getting my fuel from a local truck stop; it's the new ultra low sulfur fuel.
Any hints? Fuel pump slow to develop pressure? Injectors failing? Would appreciate any help. It's taking at least twice as long to crank/start my engine than it used to. Thanks a bunch.
Chessy56
S. Milw, WI
'01 Dmax harder to start (further information)
I forgot to include an additional symptom which may or may not be related to my hard starting. Lately, I've begun to notice my engine surging at idle. Sometimes the surging is very faint (can hear it, but it's not seen on the tach). Other times, it's more noticable and actually shows on the tach. The engine idles at ~600-650. The engine doesn't always surge; it comes and goes. Can this play into a drop in fuel pressure?
Hard starting '01 Dmax- yet more information
Don't know if this helps, but I've got further information. I have access to a Tech 2 monitor (I work for Delco in Oak Creek, WI; we made my '01 Isuzu engine controller here). I started my truck at lunch and had to crank for ~5 seconds after the glow plugs cycled. I logged ~100 frames of engine data and noted the following:
* fuel rail pressure varied at idle between 5200 and 6800 psi.
* engine rpms ranged from 676 to 703 (could heard some surging, but very mild).
* FRP Regulator fuel flow ranged from 1730 to 0 cubic mm (if stepping through all of the logged data frames, I saw an occasional frame with 0 or some reading in the lower 400 range, while most other frames logged something close to 1700. Indicative of a bad flow sensor or just lost data in the ECM???).
* Fuel regulator current draw appeared steady at around 1.4 - 1.5amp.
Does this help any? Is there other data that would be of importance? I watched the fuel rail pressure while I was cranking and it appeared to pop up towards 5000+ psi. Is my extended crank requirement beginning to sound more like injectors? Just changed my oil 2 days ago- no fuel in the oil and no signs of smoke from the tail pipe.
Please advise if there is other engine data you would like for me to capture. Thanks again for your help!