V70 T5 phase 2 help and advice re lambdas REALLY needed!!

[Paris6876]

Hi guys

Been a while since I was last here as I've had a stint away with work.

Anyhow, could really do with your collective wisdom on an issue with emissions, lambdas and general running on my V70 T5 late 2001 model.

Have bought and fitted one of Graeme Welch's 200 cell downpipes, which I have to say is a very beautifully crafted item. My Indy were very impressed and it fitted really easily. I did this as I was getting the engine management light on frequently (no loss of power, but a very restricted flat feeling, like driving into a sting headwind at 60 - 70). My Indy advised code was suggesting a 3 way cat failure. Initially, we changed the MAF, but this made no difference. So, as I love the car, I wanted to get a little more performance out of it and used this as an excuse to shell out on one of Graeme's masterpieces. All good in that respect and highly recommended.

Now, here's the issue: the engine management light has been on again for a few weeks with no significant loss of power, but my 'fluffily' feeling flat spot is back and what's worse, the car has just gone in for its MOT and failed alarmingly on emissions. NB- I Have a friendly tester who knew to do emissions with the sports cat warm. There's no fault with Graeme's work here either! What I got back in the emissions report were readings varying between 400 and 800! So... All over the shop! My friendly tester ran his diagnostics and reckons he's narrowing it down to a 'bank 1' oxygen sensor ie the pre-cat lambda.

What I would like anyone's advice on is:

A. Does this sound like it might be where the issue lies? Or... Have I overlooked something?

B. should I suck it up and change both front and rear lambdas in a last ditch attempt to sort this once and for all?

C. When it comes to buying replacement lambdas for a P2 T5 what's the forum's experience / advice: is there a good aftermarket supplier I should order from, or is it better to pay extra and get OE from my local dealership? I've read that the cheapo ones often cause issues.

Would really appreciate the benefit of anyone's experience and the forums collective wisdom and advice.

Cheers

[M-R-P]

If it's the original sensor then it's 12 years old so would probably need changing. Then there's the option of changing both... they're expensive but if one's gone, is the other likely to be far behind?

[jdavis]

Things like lambda sensors I'd be buying from dealer or sourcing genuine parts from elsewhere. You don't want to encourage the electrical gremlins on the p2

[jdavis]

Have you had the car on vida? Might give you a bit more information

[M-R-P]

Things like lambda sensors I'd be buying from dealer or sourcing genuine parts from elsewhere. You don't want to encourage the electrical gremlins on the p2

Especially an early one.

That's a point, what about the ETM?

Actually, that'll throw a different code.

[partsforvolvos.com]

you need either genuine or oe parts for the lambda sensor on p2 cars, they are too sensitive .
if after replacing the car is telling you there is still a problem, i believe what other markes do by fitting a tube spaceer for the lambda sensor might well solve the problem, but this should not be needed- you have gone for the correct 200 cel cat in my mind.
also, make sure there are no vacuum or boost system leaks, any leak in this area will cause an error in the lambda system call long or short term fuell trim bank xx.



i can probably offer them for you if you pm me your reg.

[graemewelch]

i had to change the lamdba on bank 1 on mine. it changed the way the car drove when i changed it. they known to be a dodgy if removed. or thats wwhat i was told.