Hi guys! I wonder if you may be able to shed some light on my problem.

My setup : 05 AP1, CTSC +AC (6k miles since install), 750cc injectors, uprated Pulley (9lb?), AEM EMS (mapped by mase) , Spoon Manifold wrapped, stage 3 clutch, HKS Hipower Exhaust, decat with UEGO sensor and oil presure/temp in the a pillar.

My AEM AFR gauge has begun displaying "odd" figures on WOT- I think its the sensor....... I have popped the sparkplugs out and they seem fine and the engines firing ok and flaming as normal (backing off on high revs!).

I think (hopefully) the sensor is going as the unit is reading "---" very often and when it doesn't it shows the car to been very lean around about 15 on WOT... as apposed to normally 10.9 -11.4 on WOT. It stays on "---" under acceraleration and then jumps to 14's then 15's - the odd 10 pops up then back to "---" for the majority of the time.

I have removed the bosch sensor from the decat pipe and cleaned it under a gas flame for a few seconds to reduce the carbon buildup. Didn't seem to make a huge difference.

If its not the sensor then I have a major problem? The car seems to be driving ok - no hesitations that I have noticed - but I haven't pushed it that much since I noticed it!

Bosch/AEM rate them to last 40k miles or so! But some other "tuner" forums seem to disagree! I remember reading that one guy gets through them every 12months or so!

Mase retuned the car (AEM EMS) twice - last one in late december(UK) so that shouldn't be problem. Its still spitting flames as ever so the fueling hasn't changed much - maybe the flames have killed it?

The install manual shows the correct way (10' angle) they need to be fitted to, mines at a slightly less angle in the pipe but not near the underneath at all.

Are they really only ment too last 6k miles? I have spoke to Bibbs another UK CTSC owner and he tends to agree that its the sensor failing!

I see the bosch sesnor requires no calibration unlike the others units, is that why they fail so often?