Why your engine idle is faulty

Ans. Get a specialist battery dealer to check the condition of your battery and terminals to establish whether it needs a recharge or replacement. Batteries have a lifespan, depending on their quality or maintenance.

Once you replace the old battery preferably with a 100 AH get a diagnostic computer reading to scan for faults in the battery control module and all other modules.
This is recommended in case there are short circuits that may continue to drain the battery. Besides, you ought to erase power down faults recorded in all control modules.
Ensure that non manufacture fitted accessories like audio bass bins fitted in the boot have proper connections to ensure they are switched off with the other power consumers when you turn off the ignition. You will need a technician familiar with Mercedes electrical repairs to follow this through.

Qn:My 1998 Mitsubishi Pajero 3.5cc makes a grinding sound when starting. This is not the typical bad solenoid sound but as if the starter is not engaging the flywheel properly. I have taken it to a mechanic but they don’t know how to fix it. Tom Kasadda
Ans. This sounds like your starter bendix is not moving freely enough to lock in on the fly wheel teeth. This situation can also damage the flywheel teeth. To check the operation of your starter bendix you need a qualified car technician to dismantle your starter motor. The bendix is on a helical spline on the starter shaft. When the starter is engaged, centrifical force throws the bendix outward from the starter motor engaging the flywheel. If the starter just spins, and doesn’t throw the bendix gear into the flywheel, it can be caused by low voltage, (not enough RPMs for centrifical to do its job).

Or the bendix is sticking on the starter shaft. Spray a little WD-40 on the starter shaft which the bendix rides on. Then, try and move the bendix toward the flywheel, if you can see what direction the shaft splines are heading, turn the bendix in that direction while lifting it towards the flywheel. If stuck, it may need a gentle tap to loosen it. Once free, clean up the splined shaft well, and put a coating of white grease on it.