CHECK ENGINE Lambda Sensor re-visited!!

[Saviour]

CHECK ENGINE Lambda Sensor re-visited!!

Hi all, I’m starting a new thread here because the last one seems a bit long.
So, I have fitted a new Lambda sensor today, what a palaver this has been, suffice to say after fitting three sensors with the battery disconnected, so as to reset the ECU the CHECK ENGINE display still flashes six times.
I changed the DI unit for a good one borrowed from my friendly SAAB guy, Steve of SS Motors, Southampton who also checked her over but could find nothing wrong and he advised me to run her down to SAAB Southampton to have the ECU reset by them, by plugging a computer into the vitals.
Still no joy, she’s doing 9.7 MPG at pres. I would say that is very RICH fuel/air ratio, They reset the computer and told me that there was a fault within the Lambda circuitry and I could book her in for the 1st June, ten days away, Main dealer, £50 ph, for further investigation, also saying they doubt that the fault lays within the ECU…Has anybody come across this problem before? If so how can I check the circuit for a fault? I have ten days to cure this before I let go of a small fortune for something I should be able to cure, with your help.
One unhappy Saab 9000t CS, 1997, owner.
P. S. the sensor is three wire, Black and two whites, bought from Kimbers and is Lucas OEM

[john]

Originally posted by Bacardi:
[qb]P. S. the sensor is three wire, Black and two whites, bought from Kimbers and is Lucas OEM
* * * * *[/qb][/b]

I reckon that's your problem. I have a vague memory of lambda sensors for 9000s being discussed before and someone else came to the conclusion that the only one that worked was the genuine Saab lambda sensor. Third party ones just did not seem to do it.

Can't say for sure, and someone with more experience on this than I may be able to offer a more accurate assessment.

Good luck

[mark e]

I had a lot of trouble with aftermarket Lambda sensors and in the end the problem was solved by switching to a genuine (Bosch manufacture) OEM one. Sometimes the non OEM ones work, sometimes they don't... I think you probably need to start there.

However it didn't produce the sort of MPG readings you are getting
, just a check engine light. I doubt a lambda sensor fault alone could give such bad mpg.

A few q's then...

Is the mpg accurate?
Do you get a lot of smoke on acceleration?
Have you taken the plugs out and looked at them? This could tell you a lot.

[dicreamio]

I had lambda probe problems with my old 9k, I bought an OEM one from europarts, which threw up a check engine light and the car ran very rich. To the extent that petrol fumes could be smelt from the exhaust on idling.

I put the old one back in and sent the probe back, they then sent me a different make of probe and it worked fine .

I would agree with the lads that non original probes are a gamble whether they work or not...

[Saviour]

Gen Sensor fitted, + I changed the plugs.
now we go for a run together, after 10 miles all seems GO, she is back, 'S*&^, CHECK ENGIN comes back on. I'm going to take her bake to SAAB Soton for the lot to be reset again, see if that inproves prob. mpg is better, up from 9.7 to 20.1 down to 15.4, I'll keep you uptodate Mon eve. I'm off down the pub for a swift gallon, See ya, have fun..

[Saviour]

Woops, sorry, Thans for all your input

[grentarc]

If you lived down under, i would swap you lambda sensors.. mine works, but i disconnected it so i could get a richer mixture, and no CEL came on.. and fuel economy hasnt changed. therefore i have a spare O2 sensor sitting in my downpipe (just needs a plug to go in the hole if i gave it away ie. a dead sensor )

[Saviour]

OK She is now back on the road, MAP Sensor.
If your mistress starts to drink more then she normaly does and the check engine led coms on, check the MAP Sensor first, cost more than the O2 sensor but easer to check first.
Cost of this mulfunction about £320, O2 Sensor, Map Sensor, Petrol.

[SebC]

My Saab is usually very thirsty... 21,5 litres/100 Kilometres (means about 11 miles per gallon, am I right?) Isn't this a little bit too much?


Thanks

Seb.

[Saviour]

I would say so, get the Co2 checked out. then take it from there, Petrol companys and govs take far to much money from us without giveing them a helping hand.

[SebC]

Hy! I just can't... No way to change anything as lambda+catlysator=0% Co. 'just had my technical control, and pollution was checked, nothing to matter about... Hit the road last week-end, about 200 Km, at an average speed of 70 kilometers per hour (about 50 mph), max speed 120 kilometers per hour (80 mph), decreased at 18.5 liters for 100 Km... Not so bad, knowing that, in France, 80% of the petrol price are taxes

Good night, nice dreams €€€€€€€€€€€€€€€€€€€€€€€

Seb

[MarksSaab]

I had real problems with the check engine light on my 9000 CSE 2.3T when I first got it from a main Saab Dealer. I had several Lambda sensors, a few ECU’s and many other hours work done on it (all under guarantee fortunately). In the end Saab sent a specialist from head office to look at it. I was told it was eventually tracked down to the ignition not being earthed properly. Touch wood I haven’t had a re-occurrence of this for a good few years. Goes to show it may not be what it says it is ( or that I am really gullable and can be fobbed off with any old tosh).