Can the MAF fail only when hot? (SL500)

[Unavita]

Will do.
I did check all fuses today. All are good.
I also checked the alternator. It reads good.
The battery did seem to need "reconditioning" so it is on the trickle now.
Will source OE sender.
I rebuilt lower harness myself. I can check that out. Thank you.

I should have added that the oil pressure is fine until after about 40 minutes of driving.

 

[Unavita]

Dave,

I swapped in the OEM E-gas module and all symptoms were reduced. The oil pressure is just about zero and the red light never came on.
I have the correct ignition on order. I do like the information about rotors and caps. This car was changed about a year ago. I'll have to check the exact dates and parts used.

 

[Trae]

Ok, after reading this thread, there's one simple test I would try.

With engine at idle, pull the wire to one fuel injector at a time to be sure idle changes.

If you pull one injector wire with NO change, that injector has failed.

I had one injector that would start and idle smoothly, then fail after engine warmed to operating temperature.

However, if I floored the accelrtator pedal, enough electrical current would flow to activate the failing fuel injector. When you backed off accelerating, the miss would return.

Easy test.

 

[King13ls]

I have readdd everything because I’m having similar problems with my 420,