'95 E320 Check Engine Light - PeachParts Mercedes-Benz Forum

johng99 · #1 05-07-2009, 11:05 AM

The (check engine light) CEL on my '95 E320 has come on again - after first round I changed out oxygen sensor and plugs after my Indie evaluated. Now about 50 miles later it is on again. I checked codes (thanks to this site) and am getting codes 4, 5, and 19. This is by reading the led on the car. (I have not yet made the LED code reader, but plan to do so). I have cleared the codes and drove to work this morning (10 miles) with no CEL on.
Car had the wiring harness exchanged in the past.
Any thoughts on what could be happening? Car runs very well, with only an occasional slight hesitation on acceleration from dead stop.
John

deanyel · #2 05-07-2009, 11:33 AM

Strange story - your mechanic read those codes and replaced the O2 sensor? Are you saying you don't know what 4,5 and 19 are?

johng99 · #3 05-07-2009, 11:45 AM

These are the codes that I read last night. My interpretation of the data posted is the following error codes:

4 Air injection system faulty hot film mass air flow sensor with hot wire
5 Exhaust gas recirculation faulty
19 Injectors circuit open or circuit short emission control module adaptation in engine control module at limit

My questions are: is my interpretation correct?
Does anyone have suggestions on next step?

Thanks

John

deanyel · #4 05-07-2009, 12:10 PM

It's the usual routine, clear the codes, drive the car, see what comes back. Also build the code reader, read the codes, clear the codes, see what comes back. 4 may be a bad mass air flow sensor, replace. 5 is likely a blocked EGR pipe, do a search, clean the pipe. I wouldn't worry too much about 19 until you've dealt with the other two.

Arthur Dalton · #5 05-07-2009, 12:18 PM

Classic Combo of codes on 104 HFM for broken vac line from the intake to the SOV valves for EGR and AIR system.

Pull front engine cover and look at the white plastic line going across front of engine to the two piggy-backed vac valves.....if it is cracked /broken, replace with a full rubber line. They all crack from heat fatique.
That is common feed for both SOVs and it will pop 4 and 5 together, along w/19 from the leak.

johng99 · #6 05-07-2009, 02:20 PM

Thanks Arthur - I was hoping you would give some advice. I will check in to this.