View Single Post
  #3  
Old 06-08-2015, 10:21 AM
Benz Mondi Benz Mondi is offline
Benz Mondi
 
Join Date: Nov 2006
Location: Sacramento area
Posts: 308
bad air/smog pump?

Quote:
Originally Posted by 97 SL320 View Post
I don't know for sure on this system, but typically this describes the electrical portion of the vacuum solenoid or air pump clutch. ( the computer monitors current, some systems look for an inductive kick once power to the coil is dropped. )

There is an ever so slight chance it monitors the oxygen sensor and is looking for an increase in exhaust oxygen but given it is OBD I I doubt it.
It turns on at warm up (I can see the clutch engage and hear a minor hissing sound) and then turns off once the engine is been running for a couple of minutes. It does turn on again from time to time even afterwards though.

Do this mean that it's time to replace the air injection pump?

Thanks.
__________________
03 CLK430 Cabrio 211K Pweter Silver/ Oyster Leather
90 300SEL 214k Pearl Black/ Alto Grey/Black Leather

Prior: 85 190E, 88 300TE, 89 300TE, 90 300E 2.6, 90 300TE, 92 300E 2.6, 91 and 93 300SL, 87 Ferrari Mondial Cabrio
Reply With Quote