Help please - very frequent stalling 2002 C320 W203 No Clue
Thread Starter
Newbie
Joined: Mar 2019
Posts: 1
Likes: 0
MBenz C320 W203 2002
Help please - very frequent stalling 2002 C320 W203 No Clue
Hi. My car is low mileage and been running well until yesterday. I know probably the left breather gasket is failing as there is oil all below and around this, and transmission sump gasket leaking, so will need to get these fixed as both jobs beyond my ambitions and abilities.
Yesterday, when starting off in heavy traffic (stop start) the car started stumbling and no power/acceleration for a couple of seconds, and then recovered without quite stalling out completely. Did this twice within 300 yards. I thought this might be because the car was on Fuel Reserve (though top of red level with 50 mile range) and fortunately was very close to a gas station and able to pull in and re-fill. Had already been driving fine for 40 minutes in bad traffic before this started so engine was warm.
Then with full tank, car did this stumbling, no acceleration and then recovery one more time within the next half mile.
Of course, was going to my Car Maintenance Course (!) so told the instructor and he suggested I check condition of spark plugs. I checked the first 2 of these on the LHS, but couldn't get further in the time we had. Both plug gaps were fine and looked good although we noted all spark plugs were very loose so whoever had replaced them last time had not tightened. Tightened the torque on the 2 plugs I had checked to 23nm but was having trouble reaching the others so wasn't able to tighten.
Having closed up and just reversing out of the workshop, the car stalled (in automatic mode) after running less than/about 1 minute. Car engine was still warm from previous journey. Restarted and left on idle in car park and was stumbling and stalling within about a minute of re-starting each time, revs hunting for a second or two before conking out. Put her in Neutral and raised revs and still stalled. Had to try to drive home as couldn't leave the car there, and was stalling out in the same way after stumbling briefly about every 100 - 200 yards. This was both from standing start and when driving at 20 - 30mph in town and while accelerating, so not just at lowest revs or when starting off. No warning lights. After 6 stalls in less than half a mile, had to pull over and call Road Assistance.
Mechanic plugged into a Bosch computer but there were no codes. He sprayed carburetor coolant on the Crank Shaft Sensor and I tried to drive again but still hunting and stalling. He suggested trying to drive in Manual rather than Automatic. This worked and I was able to drive at normal speeds 10 minutes to my usual garage without stalling.
Garage has been driving the car today in Automatic without it stalling once. They haven't touched anything but there's clearly something wrong and too dangerous to drive. With not enough warning time to hit the hazards when starts stumbling and before stalling or losing power, someone could drive into me. Maybe this only happens when engine is warm and they haven't driven it long enough? Can't test this myself yet as they still have the car at the garage.
I've been reading about this W203 engine stalling on here but none of the other cases exactly the same. Sounded like it could be MAF-related but garage guys said No.
Could anyone suggest possible causes? I triple-checked the air inlet pipes were fitted properly when closing up. Maybe I just put the engine cover on wrong and misaligned the bit over the big round air thing at the top - I'm short so it's hard for me to get this on so I might not have gotten it perfect although all the clips worked... Or could I have done something when checking the spark plugs? Would tightening two correctly and leaving the rest loose as they had been before cause a problem? Or could it be the breather oil leak messing up the MAF? I saw the brilliant Pelican Parts had a good article on the leaking breather gasket possibly messing up the MAF...
Completely at sea. Any ideas what could be causing this please?
PS. Only things I did to car in the course over the last couple of months was change coolant and brake fluids, tighten up a loose connection on battery, little things like change bulbs, check brake pads and re-grease one wheel ball bearing and had been running fine, but with much better braking!
Thanks much
Katie
Yesterday, when starting off in heavy traffic (stop start) the car started stumbling and no power/acceleration for a couple of seconds, and then recovered without quite stalling out completely. Did this twice within 300 yards. I thought this might be because the car was on Fuel Reserve (though top of red level with 50 mile range) and fortunately was very close to a gas station and able to pull in and re-fill. Had already been driving fine for 40 minutes in bad traffic before this started so engine was warm.
Then with full tank, car did this stumbling, no acceleration and then recovery one more time within the next half mile.
Of course, was going to my Car Maintenance Course (!) so told the instructor and he suggested I check condition of spark plugs. I checked the first 2 of these on the LHS, but couldn't get further in the time we had. Both plug gaps were fine and looked good although we noted all spark plugs were very loose so whoever had replaced them last time had not tightened. Tightened the torque on the 2 plugs I had checked to 23nm but was having trouble reaching the others so wasn't able to tighten.
Having closed up and just reversing out of the workshop, the car stalled (in automatic mode) after running less than/about 1 minute. Car engine was still warm from previous journey. Restarted and left on idle in car park and was stumbling and stalling within about a minute of re-starting each time, revs hunting for a second or two before conking out. Put her in Neutral and raised revs and still stalled. Had to try to drive home as couldn't leave the car there, and was stalling out in the same way after stumbling briefly about every 100 - 200 yards. This was both from standing start and when driving at 20 - 30mph in town and while accelerating, so not just at lowest revs or when starting off. No warning lights. After 6 stalls in less than half a mile, had to pull over and call Road Assistance.
Mechanic plugged into a Bosch computer but there were no codes. He sprayed carburetor coolant on the Crank Shaft Sensor and I tried to drive again but still hunting and stalling. He suggested trying to drive in Manual rather than Automatic. This worked and I was able to drive at normal speeds 10 minutes to my usual garage without stalling.
Garage has been driving the car today in Automatic without it stalling once. They haven't touched anything but there's clearly something wrong and too dangerous to drive. With not enough warning time to hit the hazards when starts stumbling and before stalling or losing power, someone could drive into me. Maybe this only happens when engine is warm and they haven't driven it long enough? Can't test this myself yet as they still have the car at the garage.
I've been reading about this W203 engine stalling on here but none of the other cases exactly the same. Sounded like it could be MAF-related but garage guys said No.
Could anyone suggest possible causes? I triple-checked the air inlet pipes were fitted properly when closing up. Maybe I just put the engine cover on wrong and misaligned the bit over the big round air thing at the top - I'm short so it's hard for me to get this on so I might not have gotten it perfect although all the clips worked... Or could I have done something when checking the spark plugs? Would tightening two correctly and leaving the rest loose as they had been before cause a problem? Or could it be the breather oil leak messing up the MAF? I saw the brilliant Pelican Parts had a good article on the leaking breather gasket possibly messing up the MAF...
Completely at sea. Any ideas what could be causing this please?
PS. Only things I did to car in the course over the last couple of months was change coolant and brake fluids, tighten up a loose connection on battery, little things like change bulbs, check brake pads and re-grease one wheel ball bearing and had been running fine, but with much better braking!
Thanks much
Katie
Newbie
Joined: May 2016
Posts: 1
Likes: 0
C240 2003
Hi,
My girl friend's car did something similar and it was the knock sensor. I can't remember if a code came up but, changed it once (I got a faulty from auto parts) returned it for another one and it fixed the problem for good.
I don't understand why your mechanic ''sprayed carburetor coolant on the Crank Shaft Sensor''. It might have been his way of cooling it down to see if it fixed the problem...
Good luck
Denis
My girl friend's car did something similar and it was the knock sensor. I can't remember if a code came up but, changed it once (I got a faulty from auto parts) returned it for another one and it fixed the problem for good.
I don't understand why your mechanic ''sprayed carburetor coolant on the Crank Shaft Sensor''. It might have been his way of cooling it down to see if it fixed the problem...
Good luck
Denis
