2003 M45 engine loses all power, no CEL

[psychodiagnostik]

So three times in as many weeks, I've been driving at a steady speed & the engine loses all power. The RPMs just drop to idle.

The odd thing is, the engine doesn't sputter or misfire, just returns to a clean even 900 rpm idle or so. After 10 seconds or so, while I'm frantically stepping on the accelerator, the engine responds again as if nothing happened. It's strange that the engine doesn't cut off. It's like the throttle blades suddenly return to idle position & lose all connection to the accelerator pedal for a few seconds.

Oddly enough, there's no CEL & no codes (I had to have the yearly inspection after the 2nd incident; & there were no stored codes). So there's no diagnosis for the shop to do except drive it & try to replicate, however even then I'm not sure how they'd proceed with no codes.

Could this be the camshaft/crankshaft position sensor? I've read the threads about this however there seems to always be a CEL. Also are the '03/04 models included in the recall for the soldier joints for these sensor electronics? I'm calling the dealer after the long weekend, I was just wondering.
thx!

[sstroudwku]

This is more likely the throttle body, if you look you'll see it has 2 butterfly valves. One is for throttle, one is for cruise. I've seen the one for cruise fail causing this same issue.

[psychodiagnostik]

Thanks, that makes sense. It looks like there are ~ 6 main components to the cruise control system, including the whole TB, an actuator, control unit, & release switch.

Is there any way to diagnose which component is failing? I'm really at a loss with no codes, & the fact that it's an extremely intermittent problem. I don't want to just start throwing parts at it. It's pretty scary, the third occurence was when I was with my wife on the 4 lane interstate, middle lane, 75 mph when it happened... the car slowed to ~ 30mph while I was stabbing the accelerator before the pedal "re-connected" to the engine & we accelerated back to speed like nothing happened. I'm thinking that without stored codes or the problem actually occurring the dealer techs aren't going to want to mess with it. Thanks again!

[sstroudwku]

This is one system I'm fairly unfamiliar with. I believe there is a link to the field service manual here in the forums. You can check connections for corrosion and pin tension to insure everything has a good connection. Check all the engine ground wires as well for corrosion.