Hi All, Im new to this forum but have a little DIY experience of cars over the years but still learning (or trying too!)
The car I have an issue with is actually my friends, its a ML270 and as in the title it is lacking in power and will not go above 80mph (I know the speed limit:-)) even on a long straight with the foot to the floor.
He put the car into a garage to get it checked out and they said the injector seals were leaking and this could be the issue so he had them fix this for approx £200. He is not sure is this has helped at all and asked me to check it out.
I ran some diagnostic software on it and found these results; these were taken during a 6 mile run.
Air flow rate always 8.8 g/s - not sure if it should be a constant figure
Intake manifold pressure ranges from 100 to 160 - are these average figures? We only got up to 40ish mph during the run.
Calculated load appears to move from 15 % to 65 % - not sure exactly what this means but I think this is probably normal.
Rpm works fine.
Absolute throttle position only ever gets to 38% with foot to floor - This does worry me unless my software is telling me lies, I assume with my foot to the floor it should be reading 100%?
Engine coolant temp between 50 & 55 C - again seems to be normal.
If it is to do with the throttle position is this on the pedal assembly or the other end of the accelerator cable?
If its to do with the air flow rate what could be causing this MAF?
There are no DTCs stored on the car at all although Im not sure if my software accesses the auto box ecu and if this could be causing a problem.
This is the first time I have used this software so am not 100% confident with the results given but can only go on what it says for now, I am going to try it on my car maybe tomorrow and see what results I get from that.
Again the car is a 54 plate ML270 Cdi 2.7D AUTO with 125K on the clock.
Thanks in advance.
Darren (Harry is the bloke that owns the car)
The car I have an issue with is actually my friends, its a ML270 and as in the title it is lacking in power and will not go above 80mph (I know the speed limit:-)) even on a long straight with the foot to the floor.
He put the car into a garage to get it checked out and they said the injector seals were leaking and this could be the issue so he had them fix this for approx £200. He is not sure is this has helped at all and asked me to check it out.
I ran some diagnostic software on it and found these results; these were taken during a 6 mile run.
Air flow rate always 8.8 g/s - not sure if it should be a constant figure
Intake manifold pressure ranges from 100 to 160 - are these average figures? We only got up to 40ish mph during the run.
Calculated load appears to move from 15 % to 65 % - not sure exactly what this means but I think this is probably normal.
Rpm works fine.
Absolute throttle position only ever gets to 38% with foot to floor - This does worry me unless my software is telling me lies, I assume with my foot to the floor it should be reading 100%?
Engine coolant temp between 50 & 55 C - again seems to be normal.
If it is to do with the throttle position is this on the pedal assembly or the other end of the accelerator cable?
If its to do with the air flow rate what could be causing this MAF?
There are no DTCs stored on the car at all although Im not sure if my software accesses the auto box ecu and if this could be causing a problem.
This is the first time I have used this software so am not 100% confident with the results given but can only go on what it says for now, I am going to try it on my car maybe tomorrow and see what results I get from that.
Again the car is a 54 plate ML270 Cdi 2.7D AUTO with 125K on the clock.
Thanks in advance.
Darren (Harry is the bloke that owns the car)