97 S320 extreme hesitation and lack power on hard acceleration - PeachParts Mercedes-Benz Forum

ljackson3 · #1 10-30-2006, 06:30 AM

My 97 S320 with 118K miles has two problems which I believe may be one in the same. First when the engine is cold and you attempt to drive at a normal acceleration it would not accelerate and loss power. If you very gradually apply gas it would accelerate but would not change into second gear unless I would ease off the gas pedal then reapply. After about 1 tenth of a mile it would accelerate normally from then on.

Second problem, driving at highway speed, if I perform a hard acceleration (gas pedal to the floor) it would down shift as expected, rpm would increase, but power would drop off and decelerate. I can gradually accelerate to any speed I desire with no problem.

The car receives all regular maintenance (including injector cleaner with oil change) and is use to commute 160 miles per day at 75 plus mph, other than those two issues it run perfectly.

Any advice?

pcmaher · #2 10-30-2006, 08:22 AM

There are many things that can go wrong in these cars unfortunately. I would strongly suggest you have a good technician scan each system in the car for any stored fault codes. The results will help you narrow in on the problem.

ljackson3 · #3 10-30-2006, 08:55 AM

I did pulled the error codes, P0170, P0450, P0130, P0301, P0305 and P0302 was everything on the stack....

pcmaher · #4 10-30-2006, 12:34 PM

I'll try and look those up soon...will let you know.

pcmaher · #5 10-31-2006, 08:21 AM

Quote:

Originally Posted by ljackson3

I did pulled the error codes, P0170, P0450, P0130, P0301, P0305 and P0302 was everything on the stack....

P0170 = Fuel Trim Malfunction (Bank 1)
P0450 = Evaporative Emission Control System Pressure Sensor Malfunction
P0130 = O2 Sensor Circuit Malfunction (Bank 1 Sensor 1)
P0301 = Cylinder 1 Misfire Detected
P0305 = Cylinder 5 Misfire Detected
P0302 = Cylinder 2 Misfire Detected

Certianly looks like it could be a fuel delivery problem. I don't know much about the Fuel Trim system. Maybe someone with more info can help out?

bowin · #6 10-31-2006, 09:25 AM

No harm to change/clean the MAF sensor.

david s poole · #7 10-31-2006, 09:39 AM

based on those codes the maf sensor is the problem,but the you will need to reset the adaptions.