9000 Aero MY97 - O2 Sensor problems

[antlee]

Hi, believe that my 9000 Aero (260,000km/161,000 miles) is exhibiting some low/moderate throttle accelration hesitation. Also had the CEL (6 flashes) indicating a O2 issue (although after parking the car and turning engoine on after approx. 4 hours the CEL light had extinguished). Car has never had the O2 sensor replaced. So I'm thinking, based on all indications, to replace the little bugger. So, what equivalent Bosch part number/O2 sensor should I be using. Exisiting O2 is a 4-wire Bosch unit. My Saab only has a single O2 sensor positioned on the downpipe close to the turbo exhaiust outlet. Also my car is running a MapTun Stage 4 with all the appropriate exhaust, iuntercooler, injector m odications. Thnx in advance. Cheers Tony

[Pug205GRD]

Buy a genuine replacement part from SAAB rather than a generic one. Lots of stories about hinting that the Trionic ECU is very fussy over its Lambda sensors. Cant remember if the 4 wire is the LS25 or LSH6 version?

[ontheroad]

if your running modifications it might be worth looking into a wide band type not sure if elk sell them

[AlanG]

Buy a genuine replacement part from SAAB rather than a generic one. Lots of stories about hinting that the Trionic ECU is very fussy over its Lambda sensors. Cant remember if the 4 wire is the LS25 or LSH6 version?[/b]

I agree with buy a genuine one rather than generic, but only from Saab if you have feeling rich. HelpToday or Just Lambda are both much cheaper for OEM Bosch ones, although they also do generic ones for even less.

[antlee]

Inspected my O2 sensor today. It is a Bosch LSH25 P/N 0258003662. The sensor showed a fine/thin coating which was mainll medium gray/black and a medium brown/tan in some patches. It was not heavily coated in soot. So no indication that engine is running rich. In fact, if enaything, the colour could verge on a leaner burn. Also checked spark plugs. Cylinders 1 thru 3 all displayed a light tan colour. This is quite normal relative to past plug replacements I have done. Cylinder 4 was noticeably darker - not black but noticeably darker in colour but still within range I believe. Again, plugs would indicate a normal combustion/burn. Anyway, I am going to replace the O2 sensor (with Bosch OE not universal - can be bothered splicing, etc) and plugs. I also believe that my AIC is also playing up - necver been replaced but has been taken out several times and cleaned with no obvious actuator problems. Anyway probably worth replacing this as well. BTW, I can purchase a Bosch direct replacement for half the price being asked by a local Saab dealership - not making any money on cars but certainly pumping the spare parts!! Cheers Tony