[will_c140]

M120....177k miles. When the car has recently been driven for a decent amount of time (I don't know the minimum/maximum, but each trip was between 30 and 120 minutes in these instances) and then is left to sit for an hour or 2, it is lazy to fire, and when it does fire up, it grumbles to life very slowly, before it's up and running.

No cold start issues.

No issues hot starting within just a few minutes of having turned the car off.

No issues when driving.

Only after heat-soaking/sitting for 1-2+ hours after a significant drive.

Don't read too much into it, but there is either a correlation or a placebo effect between having more gas in the tank. Drove it back from a trip with cruise on 79 for 120 miles, with short bursts to 120, then stopped off to fill up the tank. After filling, hot engine, sitting 5 minutes, it ROARED to life better than it ever has, hot or cold.

My first thought is the FPR, but I am not going to get into a 6 hour shop diagnosis whereby they still aren't 100% sure. So before we swap parts, let's get your advice.

It isn't a big deal except if it leaves me stranded, so I'd like to ferrett out the cuplrit

 

[Steve_B]

FPR is right on the money. 6 hours of shop time, give me a break -- it is a 15 minute job on the M120.

Costs $30-40 and should be replaced anyways.

If the FPR doesn't solve your problem, I am afraid you'll have to go deeper. A leaky injector(s) will be prime suspects at this point.

Steve

 

[will_c140]

I figured even it is a 50/50 shot, this is a cheap flip of the coin. Glad to hear. I don't suspect any injector issues (but you never know, of course).

I'll get working on this. Amazing how prolific these things are on the highway. Really doesn't wake up until it gets above 90 at WOT

 

[Steve_B]

how prolific these things are on the highway. Really doesn't wake up until it gets above 90 at WOT

I wish I could say something in response to that, but I cannot. I've heard it many times that the ride past 3000 rpm (and when the car has gained some momentum) is awesome.

Haven't taken my car out on the highway (and probably it won't happen).

Steve

 

[anziani]

will, you don't tell us where you live but Steve is right on that guess. I replaced mine on a 120 with only 50K. My mechanic said it was more of a maintenance item than usual. If you have the original in there you are LONG overdue. My CL600 is my magic carpet with no problems in sight for at least 60K.
Anziani