Have a wonderful 2002 E320 wagon. Only problem in past has been mice making dinner out of hoodliner, wires, anything they could chew, but only under the hood. Have had several wiring issues fixed and wiring harnesses repaired. Car runs phenomenally well for 160,000 miles.

A/C stopped working and check engine light came on. Cleared the codes, a/c worked, check engine light still on. Decided to give local repair shop w three certified Mercedes mechanics a try rather than driving hour to dealer.

Was told following codes P0135, P0134, and P0152 required bank 1 sensor oxygen sensor and bank 2 oxygen sensor. Had them replaced at fair cost.

While driving out of parking lot, no matter how far I pressed,the accelerator, the car would barely move. Engine stopped at parking lot entrance.

Hour and half later was told, 'spark plugs are arching, need to be replaced - at no expense to you.' Two hours later was told, 'still having difficulties, another hour'. Hour and half later was told, 'car no longer has acceleration issues, but, well, this is more involved than we thought, we would like to keep it overnight to replaced the oxygen sensors we just installed.

Next day was told, 'new oxygen sensors replaced, check engine light still on, still throwing same codes, we would like to keep another day'.

Next day was told, 'we are looking into a wiring issue, your service manager is out today, we will need it another day'.

My questions:

1). Do service shops usually test drive drive to make sure all is good before handing car over to client?

2). What could have happened to cause acceleration issues and necessary spark plug change after oxygen senor replacement? Car ran perfectly before oxygen sensor replacement.

3). Do service shops call client with updates, other than at closing time to tell client the car is still not ready?

4). Any ideas about where these guys should be focusing their efforts?

5). At what point do I drive the car to another shop?

Many thanks for any advice.

 

1) most just start it and move out of the garage...
2) I'm thinking the mice have a done damage to your electrical system and this is an artifact.... does the shop know the history of the mice ?
3) you could go 2 ways.... Yes they are a great shop or they don't want you to see what they have done to the car and are trying to fix it...
4) well swapping parts isn't working so they need to step back and hopefully you have told them of the mice....

5) tough call.... i keep going back to the mice damage.... if they are aware and swapping parts didn't work they are going thru your wire harness with....a multimeter... its what i would do...

 

1) I'm surprised shops don't check their work, 5 minutes around the lot could save them a great deal of time and embarrassment.

2) yes, they know of the hungry mice.

3) I guess time will tell whether they fix a pre existing issue or issue created by them.

4) they re doing exactly what you suggest - tomorrow will be a week. what's the rule before taking the car back to the dealer where it has never spent more than two days (while repairing multiple issues)?

Many thanks for your advice