My 94 E320 (140,000 miles)will decide not to start sometimes.
It may do this several times and then not do it for a month or two. It'll crank but won't fire at all. Do this several times and all of a sudden life is good and it starts right up.
Also, the engine while running, smoothly at idle, with the AC on in drive and stopped will miss, stumble, sputter and cough every time the AC cycles on and off. It may be doing this when the AC is not cycling as well as when it is cycling on/off. It also seems to have less acceleration/power from low speeds.
I have changed the fuel filter and I also replaced the spark plugs( it was missing badly at highway speeds before and when I pulled the plugs they had about an .080 gap) so after replacing the plugs the missing and hesitation at highway speeds went away.
I took it to my mechanic who said it it had a MAF code but he said he has ruled that out and now believes it is in the ignition.
Does anybody have any ideas on this? I don't want to just throw $300+ on a MAF if it doesn't need it.
Thanks,
Bob

 

wether you want it or not, you'll have to change the air mass sensor to eliminate further posibilities. by the way you describe the problem, it's either some loose wiring on the fuel injectors / engine components or the air mass sensor itself.

you got high milleage. some parts are not made to last forever, especially the electronic ones.

0.8mm gap is still normal, but still the plugs needs to be replaced every 75k miles or 1 year... whichever comes first.

 

We found the crank position sensor wire connector, located up by the battery, to be loose. When we grabbed hold of the connector it just came apart and wasn't snapped together. My mechanic said it could have been just loose enough to intermittently stay connected and then vibrate loose. He said when this happens, you crank over the engine and the sensor is not picking up the signal that the crank is turning, therefore the computer will not not send fuel or ignition causing it not to start.
Does this sound like this could be causing these problems?
It may have been that when we had the head off (had typical rt rear corner of head oil leak and front oil leak) a year ago, the mechanic didn't get the connector back together properly and it wiggles loose and doesn't make contact. So, we snapped it back together and it seems to be doing well.
Do you have any recommendations where to get a mass airflow sensor that would save me some money rather than going through the dealer? I'm going to replace it like you recommeded.
thx,
Moonbike

 

if you can give me your VIN / chassis number, i will give you the latest part number and price in euro.
from that point, you can compare the price.