Ridiculously slow 240D - PeachParts Mercedes-Benz Forum

dwoloz · #1 06-16-2007, 06:52 PM

I know the 240D automatic is one of the slowest possible cars BUT mine proves even slower

0-60 time is around 35 seconds

I've adjusted the linkages the best I can, that didn't help
I fixed the vacuum leak to the transmission, that helped a little
I replaced the dirty air filter, that didn't help

My next step is replacing the fuel filter (btw, does anyone know how to do this without getting fuel everywhere??)

What are my steps from there?

nhdoc · #2 06-16-2007, 06:57 PM

Quote:

Originally Posted by dwoloz

I know the 240D automatic is one of the slowest possible cars BUT mine proves even slower

0-60 time is around 35 seconds

I've adjusted the linkages the best I can, that didn't help
I fixed the vacuum leak to the transmission, that helped a little
I replaced the dirty air filter, that didn't help

My next step is replacing the fuel filter (btw, does anyone know how to do this without getting fuel everywhere??)

What are my steps from there?

Fuel filter and valve adjustments can make a dramatic difference. Do those two and report back on any improvements. While you are at it jack up each corner and make sure none of the brakes are dragging.

arcticathlon · #3 06-16-2007, 06:59 PM

well when i got my 240D i had the same issues. mine was a 4 speed, but i had around the same times. 0-60 was around 30 seconds +or- 60 minutes.

what my problem was that there was a vacuum line connected to my ALDA, now the 240D does not have an ALDA but an ADA(i think). only the turbo 300D's have the ALDA. well when the vacuum line was connected to the ADA (on top of the injection pump) it was horrendously slow. when i disconnected it, it would drive twice as fast.

try that, others will be able to explain why, but i know might be an issue with you.

dwoloz · #4 06-16-2007, 07:00 PM

Whats the process of checking if the brakes are dragging? Just eyeballing the caliper?

Edit: DOH! Try spinning the wheels dumbass

Nevermind then

dwoloz · #5 06-16-2007, 07:01 PM

Quote:

Originally Posted by arcticathlon

well when i got my 240D i had the same issues. mine was a 4 speed, but i had around the same times. 0-60 was around 30 seconds +or- 60 minutes.

what my problem was that there was a vacuum line connected to my ALDA, now the 240D does not have an ALDA but an ADA(i think). only the turbo 300D's have the ALDA. well when the vacuum line was connected to the ADA (on top of the injection pump) it was horrendously slow. when i disconnected it, it would drive twice as fast.

try that, others will be able to explain why, but i know might be an issue with you.

I have seen that little circular device atop the IP and have pondered its purpose. However, since I bought the car nothing has been connected to it

Richard Eldridge · #6 06-16-2007, 07:08 PM

In addition to checking for dragging brakes, before you change the filters, it would be useful to do a Lubro-Moly Diesel purge. There are three filtering devices: the small plastic secondary filter, the canister primary filter, and in the tank there is a screen. The latter will cause more problems when the tank has less fuel than when it is full.

If that still doesn't bring it up to the normal sluggish standard, then you should adjust the valves.

The Diesel Giant site has a great illustrated demonstration of how to make a purge device for cheap and use it. The tank screen will probably be reusable. Just wait until the tank is almost empty and drain out everything. An old toothbrush and dish detergent is probably all you will need to clean the filter. The O ring might need to be replaced. A bolt with a 22mm and a visegrip is probably the cheapest way to remove the tank screen.

There is a lot of info on valve adjustment on this and many other sites.

Good luck!

bgkast · #7 06-16-2007, 07:42 PM

Quote:

Originally Posted by dwoloz

I have seen that little circular device atop the IP and have pondered its purpose. However, since I bought the car nothing has been connected to it

Good! Leave it that way.

dwoloz · #8 06-17-2007, 11:28 PM

I have some Diesel Purge on order

I changed both fuel filters and there was a very subtle difference but not what I was looking for, still extremely slow

Maybe the fuel tank screen?
Planning on doing that next and also the Diesel Purge

Ara T. · #9 06-17-2007, 11:30 PM

Are you running stock tire size and are they pumped up to to spec?

dwoloz · #10 06-18-2007, 12:21 AM

Stock tire size. Rears are a little bit low but nowhere near low enough to cause this kind of slow down

Hey you're from Santa Rosa. Hi from across the way

lietuviai · #11 06-18-2007, 12:35 AM

Maybe something is slipping in the tranny or the torque converter.

dwoloz · #12 06-18-2007, 12:40 AM

Would there be any fix if that were the case?

I was planning on doing a tranny filter and fluid change, think this would alleviate that situation?

I do feel like maybe the transmission isn't transferring the power properly. The engine revs nicely and just feels like it can put out some more power than it is.

lietuviai · #13 06-18-2007, 12:53 AM

Slippage would be felt by more revving than moving. Start by looking at the color and smell of the fluid. If its dark and smells burned, then something in the tranny is damaged. I think the torque converter can be tested by putting one foot on the accelerator and the other on the brake. Then try revving the engine in gear for a quick moment if it revs high easily then its the torque converter that's slipping.
I would wait to see if someone else chimes in on this as I'm not sure if you could damage something by doing so.

dauber · #14 06-18-2007, 02:11 AM

can someone explain that vacume line hook up on top of the injection pump?
On my dad's 240D it was disconnected, he recently replaced the vacuum pump that went bad. After doing so he noticed that a vacuum line to the top of the injection pump was not hooked up so he hooked it up.

Ara T. · #15 06-18-2007, 02:35 AM

Quote:

Originally Posted by dwoloz

Stock tire size. Rears are a little bit low but nowhere near low enough to cause this kind of slow down

Hey you're from Santa Rosa. Hi from across the way

Ah Rohnert Park. I visit there a lot since my girlfriend goes to SSU. I got a speeding ticket on Expressway... watch your speed there, definite speed trap!

When you go to refuel your fuel tank and it is nearing empty, is there a big whooooosh as you loosen the fuel cap? This would indicate a plugged up fuel system.

Is your fuel filter clear? If you see lil bits of junk floating around we have some fungus amungus.