Hi guys,

I am looking at an '83 240D (manual) and it seems to take about 2/3 of the gas pedal travel just to give enough throttle to leave a stop. It's like dead space for the first half pedal. This doesn't seem normal, despite what the owner says. It seems to do okay (albeit slow) with the throttle buried into the floor. Could this just be a linkage adjustment?

Also, besides the oil cap blow-by test- any other quick engine health assessments I can make before purchasing? It had been sitting so it took a little cranking, but very minimal smoke.

Thank you!!

 

Sounds like a linkage issue. While my 240D requires some effort on the accelerator, it didn't have dead space as you describe. I think I had to replace the throttle linkage/bushing right on the firewall when I first bought the car. As for other things to check, see how the vacuum system is working, i.e. door locks, trunk lock, fuel filler door lock, if the engine shuts off directly after turning the key off, etc. Vacuum systems aren't hard to work on once you get the hang of it, but it can be a headache at times. Good luck!

 

Thanks Irastock2! !
I don't mind turning a wrench a bit, but am deathly afraid of some high dollar item being the culprit such as the fuel pump or something. I'm actually excited to learn about the vacuum system and was super impressed by the build quality of these w123s. The engine seems to shake lot, but there's no leaking and very little smoke. Smoothed out nicely once warm and quits instantly once I shut off the key too. Now I just wish I had more time for a project

 

Agree with Irastock. Look at that mechanism on the firewall that transfers pedal pressure to the throttle linkage. DO NOT adjust the linkage. It is factory set and should never need adjusting, unless the PO messed it up. The linkage however does need occasional lubrication. The Heim joints pop apart with a screwdriver for cleaning and lubricating.

IRT shaking, one of the most commonly ignored (by the uninitiated) maintenance items on our engines is the valve adjustment. It is fairly easy to do about every 10 to 15k miles and will leave you with a much smoother idle and a great feeling of accomplishment. Other common sources of rough idle can be air in the fuel system, dirty fuel (look at your clear plastic primary filter) and rarely bad injector nozzles. I say rarely because injectors should go about 100k miles without need for rebuilding.

These are great engines and dead nuts easy to work on.

 

I wanted to circle back and thank ya'll again. I passed on that 240d, but ended up picking up a neighbor's '82 300d- definitely bitten by the w123 bug. It's been a nice pandemic project with the basics all handled (these cars really are nice to work on) and just tie rods to swap next. Happy motoring!