QuestionDear whunter, we have a 300E with a stalling and re-starting problem! The customer complained a few month ago about this and explained that it would usually re-start after cooling down. I have driven this car for several hours and until last week it did not happen(at least to me)! Last week I was going to take it to an inspection and it suddenly cut out once going uphill(after warm-up) and then going down it stalled and didn't re-start! After a few hours the car was broughtby tow-truck to our shop and it started again, running ok!
Then, after warming up it stalled again and didn't re-start, it sounded like the timing was out and it was missfiring. We checked so far the following items, e.g. tried replacement items:
Fuel-Injection Metering Head, Ignition Module, T.D. Sensor on bellhousing, Overload relay, fuel-pump-relay, Distributor Cap&rotor are good new items, leads, surpressors and plugs all near new.
Checked fuel filter, is near new and open.
The engine has lately developed an oil-leak on the rightrear end of the cylinderhead and started to use oil, I believe more than being caused by the leak, but doesn't blow smoke from exhaust.
After all this, is there a possibility that the converter is blocked, because very time the engine starts to stall and splatter, the converter heat light comes on for a few seconds?
It actually backfires through the intake manifold and airflow-measurung unit and really sounds like the timing is way out. After cooling down to below 40 degree Celsius it will eventually re-start, but as soon as it reaches 80 degrees or above it will start runnig rough, splattering and when engaging into gear it will stall. Have checked plugs for flooding, but dry. Also checked temperature sensor and seems to havecorrect resistance at 80 degrees C (about 32 OHM).
Could it be that the converter is causing all this trouble? We have got another 300 Merc with similar problems, but it has no converter. Would be pleased if you had any suggestions for us here downunder!
Anxiously awaiting your reply!
GERD
AnswerI am assuming you have a 300E, not the 300E 2.6 or 300E 4-Matic.
How many miles/kilometers are on the car?
Answer:
As you are a mechanic, here is a simple diagnostic.
With the vehicle on a lift.
Use a strap or three to support the exhaust system.
Remove exhaust bolts holding pipe to manifold.
You need at least one inch or more of space between the exhaust pipe and manifold outlet, might want to use some tin sheet to shield the bulkhead from hot gasses.
Eye protection needed here; Stay away from the exhaust, it can spew or spit burning oil.
Start the car, and bring it up to 80C.
If there is no change in operation, and it is possible to take it on the road in this condition for a diagnostic drive, this would prove the Catalytic Converter is or is not the issue.
The normal reason for converter failure on this model is valve guides and seals.
Please focus on this car for the moment, the other can wait it's turn.
I am on a forum you may enjoy looking at.
http://www.rroc.org.au/
Best to you.
