That shop is telling you they don't want the job. If you want someone to do the job for you then I'd look for someone else.

I feel your pain! This is the kind of situation that pushed me into figuring out how to do these jobs for myself. It may push your skills and patience, but it's far from impossible:

OM606 Glow Plug removal Tips and Tricks

'95 E300D - Fully Unthreaded But Stuck Glow Plug

That shop is practicing good business by being upfront and letting the customer know the reality of the job of best or worse case scenario. The 606 glow plug job potentially has a whole different set of rules compared to the 617 or 603. You never know how that job will go until you're already into it. Customers usually prefer that than the dreaded unexpected phone call of how their $500 job escalated to big $$$$. They then have the option of backing out before the job is started. We always tell them the low and high end. when it's low, they're happy. When it's the higher, they're prepared, but not irate.

Paul, you've raised a good point, and you've caused me to examine more closely what I don't like about the situation as described by packerfan. Thanks for that!

Yes it is good and proper for a shop to manage expectations around a potentially complicated and expensive repair. I believe there's more than one way of doing that, given the job of replacing GPs in an OM606.

My thought about packerfan's experience is that I'd want to know my bill was going up from $500 to $2000 well before being called to pick up the vehicle. I'd want the chance to say "stop there" before taking on $1500 more in charges. It's as if the shop is giving itself license to bust off glow plugs and send the head out for repairs willy nilly.

From my own experience with OM606 glow plugs I'd venture that a experienced mechanic knows when a GP is so tight they risk breaking it off, and can stop before that happens. If I were the "shop" in this case I'd be willing to take a look at the GP situation, for a fee, and provide options and set expectations from there. If I were looking for a shop to do the job for me that's what I would want.

That's how I work when estimating repairs to the old watches I work on. I charge a fee to take them apart and have a look before providing a detailed estimate. Works pretty well. It allows me to provide a more precise idea of what the maximum charges will be or could be given different scenarios/options.

Sorry to have taken this thread a bit off the original topic.

Yes, just a simple phone call works wonders with customers. We don't spend one dollar over an estimate without a phone call. In the case of the glowplug removal, if we find that we're going to run into a problem we make the call to discuss how they want to further approach the situation. Whether it be go for it, stop or just replace the ones that will easily come out. It's always their call. We can only throw numbers at them and advise....yes, sorry for straying off topic.