300TE Problems........

[RhodieBill]

Hi guys, I am new to the site so forgive me if this has been asked before...
I have just bought a 1988 300TE Auto 165,000 on the clock (aprox)(one of the problems)....here goes.....

1) Have trouble starting when engine is cold, have to play (gently) with the throttle to keep it running. Once warm (4mins) is ok. If I try to engage drive before then, just stalls. Automatic choke maybe?

2) Idling seems very low, and roughish. Can I adjust?

3) Odometer & trip not working, previous owner said he used to get it working by playing with the trip reset button, but now it doesn't. Stopped on 152,000 exactly. Any ideas?

4) Interior light works when manually switched on, but doesn't work when doors are opened, although you can hear a clicking noise behind the dash when you press the button in and out, fixable?

5) Rev counter doesn't work properly, when doing 70mph it reads 1500rpm.

There is also one other thing which I haven't got a clue as to what it is. There is a sort of Dial, about 1inch in diameter in the compartment with the battery which has numbers on and also N & S. You can pull out this dial and turn it to another number and push it back in. Any ideas on this one, theres nothing in the owners manual about it.

Anyway thanks for a great forum, and am hoping to hear from some of you soon.

Ciao, Bill.

 

[Orlando 300E]

Hello Bill,
Your starting & idle faults could all be relating to one problem -I may not have the correct answer, but here goes.

I think your difficult starting could be down to a duff alternator -check the output with a multi meter you should be getting round about 14v if it?s healthy. I have had two alternators give up the ghost with mine -each time for about a month before, I noticed it required a bit more cranking to get started.

The dial you talk about adjacent to the battery is the ignition trimming socket -you only need to adjust this is you are going some ware with doggy low octane fuel or if you are running exclusively on super unleaded -check the owners manual. If you have fiddled with it, this could be your idle problem.

Good luck
Orlando

 

[Arnie]

Hi,

By all means check the alternator, but my guess would be first to look at the ignition leads, plugs, distributor cap and rotor. If you replace them make sure that they are Original MB (Bosch) parts. Others will not work for long.

Then, if these are all in oreder check the fuel injection system and particulary the cold-start valve, which should operate to allow more fuel-in when the engine is cold.

Also worth checking is the infamous OVP relay (the one with a fuse on the top) which controls the valve and fuel-pump. However, if this fails you normally see an ABS warning light come on, as it provides power to this too.

Idling is controlled electronically by the engine control unit, but if your tacho is not working correctly, then you may well have a problem with idle RPM also. Some engines use a magnetic sensor on the front crank-shatt pulley for the RPM, others use the iginition system signals.

The adjustable plug with N & S should be left in the S position for fule above 92 octane.