my 2002 sl500 has codes p0173 fuel and trim malfunction bank 1 intermittanly at times ok for a week car seems to run perfectly fine ?? any help please e-mail jbedros1@comcast.net

 

The areas I'd concentrate on would be:

1) MAF Sensor (clean with CRC MAF Cleaner available at AutoZone, et.al)

2) Check/test the forward O2 sensor on the left(driver's side) it could be failing

3) Check fuel pressure (accessed at the front of the engine at the end of the fuel rail) you could have a weak fuel pump or more likely a dirty/clogged fuel filter

Do us all a favor, post what you find out

Bob

 

ended up going to mercedes mechanic who claimed the cleaning of mafs was not recommended. said replacment was so i had him do it for just under $500. because i put the car up for sale i thought this was best solution. thanks to sunguy62 for the advice. i'm really not happy about decision to sell my silver arrow but its time. thank you for responces

 

I'm glad you got this resolved, but sorry you had to part with $500 to do it. While I'll never be mistaken for a Mercedes mechanic, I do know what works on specific problems because I've done it.

The MAF sensor itself, inside the cylinder/holder, is made up of a piece of thin film and an electrified sensor wire. As long as both of these subcomponents are intact, cleaning is all that's necessary. The MAF cleaner I cited is little more than electrical contact cleaner (read alcohol) and will not harm anything in the MAF Sensor, it simply cleans the debris that accumulates on the sensor wire that gets through the air filters. Therefor I respectfully disagree with your tech about this.

Frankly, the cleaner costs $5.00, replacement in your case, nearly $500.00; if this same situation appears for anyone, try cleaning first. When the same thing happened to me 20,000 miles ago, I used the same cleaner I mentioned and the problem was solved.

Good luck selling your car; Silver Arrows don't come around that often.