Interpreting OBD data

[taznuv]

Hello, have just got a OBD to usb lead, and have been trying to diagnose a problem on a Ford Ka. Would really appreciate any advice/suggestions on the data I collected, and where to look next. The symptoms are running away/holding revs between changes, and higher than normal fuel consumption. Most people say the idle control valve but it's clean and I'm not 100% convinced. The figure that seems odd is calculated load: 40% at idle? New to OBD so may have missed something obvious here:

the data:

Throttle: 13 -93%, 12% when cold

Load: 30-42% at idle, going 100% early?, 18-20 on overun

Temp: 93

Oxygen sensor: switched rich to lean, tends to be rich, long term trim 2% rich

Idle speed around 880, but often higher, slow to return

Speed: accurate

Tests: all show completed

Map: 14.5 engine off, 5 warm up idle, quick to respond, looks clean

Idle control valve clean

thanks

[Diag]

Hi,

Your OBD data (or EOBD if pedantic like me) does not contain enough info to diagnose a problem like this. The ECU is capable of outputting a lot more processed data than a simple OBD/EOBD tool is capable of reading.

Without knowing more detail on the car its difficult to advise you but you could try resetting the KAM. This is simply done by pulling a fuse. I cant recall which fuse but it is a 3 amp and is marked as being for the EMS. It is safe to pull any of the EMS fuses. This alone could fix the fault.

[taznuv]

Thanks for the advice diag.

[skid-mark]

your throttle and load % should only rise while the engine is being reved/driven if your getting high % readings while your just ticking over then that would sugest you've got incorect readings and could have a faulty throttle pedal sensor or position sensor if it has one.
normall throttle readings at idle are around 8-15% and should read 98-100% fully depressed
engine load is around 25-40% on idle and should rise steadly as more load is applyed.

[taznuv]

Thanks skid mark for providing some typical values, it does suggest throttle position sensor fault, this has been adjusted in the past, may try a replacement.