zuluyankee
13-11-2009, 09:34 PM
hi all, i have a 57 plate A5 3.0TDi 47,000 miles.
following my 40,000 mile service i have experienced total loss of bottom end torque with top end feeling strained also.
the dealer had replaced oil, air and fuel filters along with a new air mass meter (on account that the meter housing bracket was broken and a couple of wires looked loose..??)
until this point i believe performance was exactly how it should have been as always - plenty of pulling power throughout the rev range. following the service, lag was experienced until 1,800rpm then as above, the rest of the rev range felt strained.
i have since had the car back to the dealer twice.
1st revisit i was told the settings for the air mass meter had been altered. improvement however within the lower end albeit still serious lag again to the same point. i had the car dyno'd the day after and whilst it produced correct hp and 550Nm, 500Nm was reached at 2,250rpm.
2nd revisit this week lasted two days of investigation and tweaking of 'basic engine management' there is still a seriously bad lag but when peaking torque it is more brutal than standard. fine you say but this has also affected mpg.. i am told it is running within audi tolerances and i know what these are after shocking software updates to your engine management!!
i've searched to no avail so there are a couple of things i'd be really grateful of some help on if anybody could;
1. i cannot find a standard 240PS 3.0Tdi dyno map so that i can compare against mine. it would be helpful to prove that max torque as you feel and as you hear is indeed available between 1,500 and 3,000rpm. if anyone can point me in the right direction that would be appreciated.
2. anyone got any ideas?? i like a good conspiracy theory - they're usually right!!
i appreciate it's some heavy reading, take your time..
james.
following my 40,000 mile service i have experienced total loss of bottom end torque with top end feeling strained also.
the dealer had replaced oil, air and fuel filters along with a new air mass meter (on account that the meter housing bracket was broken and a couple of wires looked loose..??)
until this point i believe performance was exactly how it should have been as always - plenty of pulling power throughout the rev range. following the service, lag was experienced until 1,800rpm then as above, the rest of the rev range felt strained.
i have since had the car back to the dealer twice.
1st revisit i was told the settings for the air mass meter had been altered. improvement however within the lower end albeit still serious lag again to the same point. i had the car dyno'd the day after and whilst it produced correct hp and 550Nm, 500Nm was reached at 2,250rpm.
2nd revisit this week lasted two days of investigation and tweaking of 'basic engine management' there is still a seriously bad lag but when peaking torque it is more brutal than standard. fine you say but this has also affected mpg.. i am told it is running within audi tolerances and i know what these are after shocking software updates to your engine management!!
i've searched to no avail so there are a couple of things i'd be really grateful of some help on if anybody could;
1. i cannot find a standard 240PS 3.0Tdi dyno map so that i can compare against mine. it would be helpful to prove that max torque as you feel and as you hear is indeed available between 1,500 and 3,000rpm. if anyone can point me in the right direction that would be appreciated.
2. anyone got any ideas?? i like a good conspiracy theory - they're usually right!!
i appreciate it's some heavy reading, take your time..
james.