BenzWorld Junior Member
Date registered: Jul 2015
Vehicle: 2000 ML430 2003 ML500
Location: British Columbia
Mentioned: 0 Post(s)
Quoted: 7 Post(s)
2003 Ml500 backfires, stalls. CKP replaced already.
I hate to start another of these threads but I'm running out of ideas.
I've had this car a couple months now. Shaking the bugs out of it for the wife to use. Got the traction control issues dealt with, thought I had the stalling problem fixed but it keeps rearing its head.
This NEVER happens when I'm driving. Car apparently bogs, lights on the dash blink like vegas, stalls and wont start again. Leave it for a few minutes and it will start again and drive like new.
One time when this happened it backfired so loud it sounded like a gunshot in the cab. The wife is hesitant to drive it now, and I pretty much have the other ml sold... so I had better get this sorted.
I replaced the ckp with a new Bosch a week ago, apparently no change. Spent today cleaning up all the battery connections, changed out the MAF with a spare I had kicking around, opened up the electronics nightmare in the engine bay and wiggled all the wires and engine harness while it was running but not even a stutter.
Fuel pressure is fairly steady a few PSI short of 60, doesn't fluctuate for more than a few milliseconds if the throttle is stomped.
I was told the pump had been changed, but not 100% sure of that fact now that I have pulled it to inspect. The access cover HAS, previous to today, been removed and installed with a non-OEM sealant.
Aside from this fairly extreme fault, the car runs awesome. Especially when I drive it.
There are no codes that show themselves when this fault occurs, however I usually have a pair of catalyst inadequate efficiency codes because the PO gutted the cats.
I also have a persistent P2039-8 oil level sensor code. On occasion the low oil light comes on in the dash, but I am 100% positive the oil level is adequate.
I caused a litany of codes today unplugging and plugging things in, cleared out the codes, waiting for Amanda to drive it to see if it faults again.
I have found threads where the ignition switch is suspected, so I spent some time wiggling it around, beating on the dash and steering column with my hands but not even a hiccup.
Sort of lost for direction at this point... any input is welcome.
Thanks for looking.