My99 running lean?
 

Hi,

Right i think my 99 uk turbo is running lean all of a sudden as my afr gauge used to show blue at WOT but lately has been showing amber, also i feel the car has lost a bit of power, certainly doesnt feel as strong as it has done.

Im using the car for work at the mo as my diesel workhorse is kapput and have been driving like a bit of a grandad to and from work, but would this relaxed driving retard the timing or is something on its way out, as in the maf or o2 sensor?

The idle on car is spot on and the only real difference is the amber light on the afr gauge and definatly a less urgent power deliverly.

Really need some advice as bit worried about causing any damage anywhere?

Any input gratefully recieved:)

THe My 99 is known for having a weak maf sensor, if thats on its way out it can make the engine run lean. The lambda sensor might be failing but that usually causes rich running but if the sensor is where the reading is coming from is not giving out correct voltages then its not going to read correctly.

have you tried checking the ecu for fault codes?

Rich

No i havn't tried reading any fault codes, probably will just book it in somewhere i think as i dont have any diagnostic stuff but i thought an uneven idle was a sign of maf failure? my idle is spot on and engine is very smooth also?

Thanks for your input, matt

do a search on here for reading the codes as its just a couple of connectors under the dash.

Had exactly the same on my MY99. Idle was perfect but a delta dash run proved the maf was failing. The ecu fault code thingy won't show a failing sensor - it will only show a failed one.
If it is your maf failing then your ecu will be trying it's hardest to compensate for it - so if for instance you did an ecu reset you might just find your car does idle badly.
If you are unsure about your maf, i would replace it anyway - £80 is less of a slap in the chops than a £4k repair bill - lean running will, sooner or later end the engine :thumb:

Brun,

Cheers for the info, thing is the maf was replaced less than 10,000 miles ago, do they really only last that long!?

Will defo change it though, but would it be ok for a week if stay off boost or just leave it on the drive and take the other halfs car?

cheers matt