High Flow Cat. = Weak O2 Sensor

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bem_ho
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High Flow Cat. = Weak O2 Sensor

Post by bem_ho » Wed Oct 22, 2003 9:26 am

I have installed the Miltek 200 cells high flow cat. for over 2 month and am very happy with its performance given to my car. However, I have found my O2 sensors are not very happy with it and caused the engine light to come on in many occations.

Is this normal? Do I have to keep on changing sensors? Or is there something I have done wrong during installation?

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Re: High Flow Cat. = Weak O2 Sensor

Post by Jon » Wed Oct 22, 2003 2:00 pm

That happened on mine bem.....couldn't find a fix for it. The sensor isn't weak it's just that the cats aren't getting hot enough so it throws a check light. You could try "lagging" the cats with some kind of insulator. It helped mine a bit..but on cold days it still cam on.

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Re: High Flow Cat. = Weak O2 Sensor

Post by bem_ho » Thu Oct 23, 2003 3:49 am

Thanks, Jon.

However, did you realised that the sensors are placed differently on the Miltek Cats??

With the OEM cat, the sensors is placed before the entry side but with Miltek, it is placed after the exit side!! Strange??

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Re: High Flow Cat. = Weak O2 Sensor

Post by Jon » Thu Oct 23, 2003 9:42 am

thats what causes the problem...but mine were 100 cell....miltek told me that the 200 should not do it so I would have a word with them

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Re: High Flow Cat. = Weak O2 Sensor

Post by Bushy » Thu Oct 23, 2003 10:49 am

I have 200 cell cats, have you remapped again after fitting the cats?

Once the high flow cats are fitted the fueling needs futher adjustment to overcome this problem

What remap have you got?
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Re: High Flow Cat. = Weak O2 Sensor

Post by bem_ho » Thu Oct 23, 2003 1:11 pm

Bushy, I've got ABT!! Does it need remapping??

Can ABT ECU remap by Revo??

However, the strange thing is that the light comes on after 2 months of use!! Ummm.... [img]images/graemlins/acclaim.gif[/img]

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Re: High Flow Cat. = Weak O2 Sensor

Post by Bushy » Fri Oct 24, 2003 7:57 am

I am not sure, better contact Abt and ask them about a further remap

The light may have just come on because of a certain driving style you did, but basically if the fuelling is wrong at high revs, i.e it is under fuelled you could cause the engine to blow as the additional fuel aids cylinder cooling and hopefully avoids pre detonation in the cylinder

I guess speak to Abt and let us know what they say

Good luck
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Re: High Flow Cat. = Weak O2 Sensor

Post by bem_ho » Fri Oct 24, 2003 9:15 am

The light only comes on when the car is at a stand still!

I have air/fuel ratio gauge on my car, it indicates the air/fuel mix is healthy when running in high rev range. Umm....

Oh well, Revo will be in HKG next week, may be they can have a look for me. Meanwhile, I will speak to ABT for solution! I'll keep you guys on tap!

Bem

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Re: High Flow Cat. = Weak O2 Sensor

Post by Jon » Fri Oct 24, 2003 12:44 pm

mine only did it traffic or when stood as well bem if that helps. Whenever you change any exhaust or engine part you should get the chip remapped to match it to the component changes.

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Re: High Flow Cat. = Weak O2 Sensor

Post by bem_ho » Sat Oct 25, 2003 3:04 am

Thanks mate!!

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