I have a 1991 300ce 24v. The problem is that it runs lean and runs out of fuel at around 5000rpm.
Actually when reving at neutral you can hear missfire around 5500 rpm.
The spark plugs are a bit white (and have been replaced and also tested leads cap, rotor)thats why I know it is running lean however it does not overheat.
I can safely discount the igintion system.
Also when trying to start when hot after about 5 minutes you have to start it twice.The first time it revs up for about a second then dies and second time it is fine.However if I put my foot doen a little when starting then it is ok.When colder start no problems first time.
It idles well and as long as you dont push it it drives fine.
I have replaced the fuel pumps and fuel accumulator and have purchased new injetors but I havn't installed them yet.
I have adjusted the on off ratio to 50% at idle but when you put your foot down to 2500rpms it drops a little.
THe fuel ditributor looks like it has been replaced because it has a remanufactured sticker.
I know I need to test the fuel pressure but I dont have a guage.
Has anyone had this problem and has any ideas what this may be and is a pressure guage the only way to diagnose?

Thanks

Kaz

 

You could try adjusting the EHA out by up to 1/4 of a turn. The EHA is the black box on the side of the fuel divider.
Remove the EHA, remove the screw that you will then see, then using small hex key, turn the inner screw counterclockwise by 1/4 of a turn. Record how far and which direction you turn it in case you need to adjust it back. See how this goes.

 

Thanks for the tip and I will try it but these do not normaly require adjustment. I would like to get to the root cause of the problem or are you suggesting that the EHA valve is causing me proplems?

 

Yes, also check the inline filter at the divider, but I don't think it will be causing your problem. It is the brass connection on the intake pipe.

 

Hi.

I have checked that already before and it's fine.

I have also replaced the main fuel filter

 

I suggest you just try the EHA adjustment first. It is reversible, and costs nothing. Let me know how you go.

 

Hmmmmm,................Having thought about this, the direction should have been clockwise.[sm=sorry.gif]

I hope you have documented what you have done. Also try just 1/8th of a turn for starters. If you go too far you will increase your fuel consumption. Good Luck.

 

also check the air flow sensor indicator with engine running.

higher value is 4.6 - 5.1 volts and lower value is 0.55 - 0.95 volts.

loosen the adjusting screw (concealed with plastic cover) on the side if you need to adjust.