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Some newbie questions, '79 240D

830 Views 7 Replies 4 Participants Last post by  MBeige
I saw the car online and couldn't not stop when i passed on my way to school. The link can be seen here:

First off:

What is that switch to the left of the ignition? it has very little resistance and I almost think it doesn't work!

some more:

I'll track down the vacuum stuff on my own, the locks are sluggish and I'm guessing its a leak somewhere, I hear this is very common.

When starting cold(driving, not engine starting) the transmission(automatic) shifts hard for a few times, is this vacuum related as well?

When putting it in gear, the back end jumps, I know rear-drive cars are different(my other car is a neon) but I am not sure this is normal! Could it be the engine idling too high?


There are a few dried up bits of vinyl and rubber. Can youall point me to some web sources for pieces? We dont have a lot of these cars left in alabama, theyre all but extinct! thanks in advance for your time and i hope to not post alot!
1 - 2 of 8 Posts
The hard shifting could be vacuum related but it may just be cold. Remember that diesel transmissions shift a little harder and differently from a gas car. Addressing any vacuum leaks and modulator and bowden cable adjustment may smooth things out – oh, and don’t forget to find out when the ATF and filter were last changed, I’ve seen a simple change do wonders.
When cold the op should be at 3 bar all the time, under load or at idle. When the engine warms and the oil thins, it is normal for the op to drop as low as 1.5 bar – but as soon as the throttle is touched the op should spike back to 3 bar. If not the car should be checked by a mechanic, it may be a bad gauge – or a bad pump.
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