Strange starting problem '94 E280

[robparker]

Wonder if anyone can help with this. I have a 1994 E280 with 119k and i have 2 problems. 1st is a hunting idle which occasionally stalls and i think thats the air mass meter which is on order at the moment. The other is a starting problem, usually when hot, where i will turn the key and it will barely turn over, sometimes not atall, like it has a completly flat battery. Turn off and re-try and it turns over like it should and starts right up. The battery is brand new (replaced a week ago). Any ideas what this could be?

 

[kth286]

Possibly bad/rusted/loose earth between engine and chassis and battery causing the starter circuit to be variable, like you are experiencing.

Look for the thick wires and make sure all are tight and no rust around the connection points.

 

[robparker]

Hi, i have just had a look and the negative cable that earths on the chassis looks to be tight and rust free. Are there any more i should check? Even on the times when it doesnt even turn over all the dash lights come on as normal and then slightly dim when trying to start (as normal) even though nothing much, or nothing atall happens.

 

[kid-jensen]

rob,

When you get the problem of slow cranking, keep it up for as long as your mechanical sympathies will allow, then go round feeling the temperature of the joins in the heavy wires between the battery and starter motor (via the solenoid). Any joints where high resistance is creeping in will reveal themselves by getting hot. It's only a case of remaking and cleaning the joint then....

If you can't tie it down that way, check the volts-drop across the solenoid, (from the battery feed terminal to the starter output terminal). It shouldn't be more than a couple of volts, preferrably much less..

 

[television]

If none of the earths or live feeds are getting hot , then it will be the starting motor. a check would be to put a meter across the live to measure the voltage while cranking

 

[robparker]

Hi, thankyou everyone for your prompt responses. It turned out to be a knackered starter motor in the end. Its getting replaced tomorrow

 

[Cosworth]

I'm currently breaking a mercedes e280 W124 1995, lots of parts, let me know if you need anything.