[Mike57]

Had my 2009 Jimny booked in today to have extractors fitted and a sports muffler.

The installer took the manifold off and discovered it had a prefilter or some sort of manifold cat as part of the manifold in addition to the main catalytic convertor. He did not go any further and needs to work out what this prefilter in the manifold does. He had not seen it on earlier model Jimny's.

Does anyone know what this manifold cat is and how to fit extractors while keeping the car legal?

[zook91]

as long as you have a cat further down it should remain legal
the swift sports have 2 cat converters, 1 in the manifold and 1 down further, no idea why but the same with those guys put extracotrs on then have a cat further down, not sure if it will with the jimnys but it could throw a cel but its not anything to be concerned about

[steak_knife]

zook91 wrote:

as long as you have a cat further down it should remain legal
the swift sports have 2 cat converters, 1 in the manifold and 1 down further, no idea why but the same with those guys put extracotrs on then have a cat further down, not sure if it will with the jimnys but it could throw a cel but its not anything to be concerned about

But the ecu doesn't care about legal

Thay run 2 O2 sen's, upstream (before cat) & downstream (figure it out) to see if the cat is doing it's job, take that cat out & it will throw a code & you ecu will put the car in limp home mode....


Have fun....

[Gwagensteve]

Many cars now run two cats. one is small, close to the motor and offers little restriction. It's designed to heat up to temperature as quickly as possible to provide emission control soon after start up. the second cat is there to work once the car is up to temperature and the small cat is no longer effective.

Remove emissions control equipment at your own risk.

Steve.

[monley]

If the new extractor's have a pipe for the EGR and a place for the sensor it will be fine then

[Scrawny]

monkey wrote:

If the new extractor's have a pipe for the EGR and a place for the sensor it will be fine then

How will it be fine?

[monley]

Scrawn wrote:

monkey wrote:

If the new extractor's have a pipe for the EGR and a place for the sensor it will be fine then

How will it be fine?

It won't throw code's if it has the ERG pipe!

Sorry just re-read the OP NFI about legalities on the cat.

[zook91]

steak_knife wrote:

zook91 wrote:

as long as you have a cat further down it should remain legal
the swift sports have 2 cat converters, 1 in the manifold and 1 down further, no idea why but the same with those guys put extracotrs on then have a cat further down, not sure if it will with the jimnys but it could throw a cel but its not anything to be concerned about

But the ecu doesn't care about legal

Thay run 2 O2 sen's, upstream (before cat) & downstream (figure it out) to see if the cat is doing it's job, take that cat out & it will throw a code & you ecu will put the car in limp home mode....


Have fun....

yep and like i said so do the swift sports (yes i know we are talking about a jimny but its all the same) and loads of people have just switched to 1 cat or even knocked both out.... and the car runs fine, again not saying the jimnys the same but i doubt it would be much different

[steak_knife]

So your saying the downstream sen is fine with not having cat's????

[steak_knife]

zook91 wrote:

yep and like i said so do the swift sports (yes i know we are talking about a jimny but its all the same) and loads of people have just switched to 1 cat or even knocked both out.... and the car runs fine, again not saying the jimnys the same but i doubt it would be much different

Tell em they are killing innocent dolphin's

[zook91]

steak_knife wrote:

zook91 wrote:

yep and like i said so do the swift sports (yes i know we are talking about a jimny but its all the same) and loads of people have just switched to 1 cat or even knocked both out.... and the car runs fine, again not saying the jimnys the same but i doubt it would be much different

Tell em they are killing innocent dolphin's

haha yep i know, but unfortunately they dont care.... iv still got mine in

[steak_knife]

steak_knife wrote:

So your saying the downstream sen is fine with not having cat's????

[zook91]

steak_knife wrote:

So your saying the downstream sen is fine with not having cat's????

well yea, like i said it does throw a CEL but it does that even if you put a CAI on so i think its just over sensitive, but even with the CEL its not in limp mode. but it could be different for a jim im not sure

[steak_knife]

zook91 wrote:

steak_knife wrote:

So your saying the downstream sen is fine with not having cat's????

well yea, like i said it does throw a CEL but it does that even if you put a CAI on so i think its just over sensitive, but even with the CEL its not in limp mode. but it could be different for a jim im not sure

Also never heard a MIL called a CEL...

[royce]

steak_knife wrote:

steak_knife wrote:

So your saying the downstream sen is fine with not having cat's????

I don't believe a catalytic convertor creates oxygen so how would the sensors know?

[steak_knife]

It read's the Co2 level's & the heat of the gas's....

It' whole job is to see if the cat is doing it's job, if the cat's not it dobs it in to the ECU & the ECU log's a " catalyst inefficacy" code & turn's the MIL on....

[royce]

steak_knife wrote:

It read's the Co2 level's & the heat of the gas's....

It' whole job is to see if the cat is doing it's job, if the cat's not it dobs it in to the ECU & the ECU log's a " catalyst inefficacy" code & turn's the MIL on....

The scoundrels!

[steak_knife]

[Fatzook]

steak_knife wrote:

It read's the Co2 level's & the heat of the gas's....

It' whole job is to see if the cat is doing it's job, if the cat's not it dobs it in to the ECU & the ECU log's a " catalyst inefficacy" code & turn's the MIL on....

Let me guess......

It automaticly charges your credit card for the replacement parts too

[pyrohamish]

Sounds like you just need to put a resistor in the line to trick it into thinking that everything is fine

[boostedbrick]

If there is two sensors and two cats, presumably one is after the second cat to insure its working, so presumably removing the first cat will do nothing but remove some restriction yea?...

My old astra had the twin cat/twin sensor bullshit, all it did when I removed the cats was turn the CEL on. Which was then cancelled and never returned.

[JrZook]

I thought one was a pyro and the other was an O2 sensor. The pyro being there to ensure that the cat don't overheat and die.

[Mike57]

Thanks for all the discusson. Given the range of opinions expressed so far I need to do a lot more research on this one.

I don't want to remove any emission control equipment that is required by law. I do want to fit extractors. I need to find out if the two aims are mutually exclusive.

The only hope I think is that maybe the extra cat was added to satisfy the more stringent European regulations and that in 2009 the Australian emission control regs were not so strict. Then of course I need to work out whether modifying the car in this way would be legal anyway and then if it is allowed how to overcome any issues with the ECU.

When I find the answers I will let you know. This might take a while.

[monley]

Mike57 wrote:

Thanks for all the discusson. Given the range of opinions expressed so far I need to do a lot more research on this one.

I don't want to remove any emission control equipment that is required by law. I do want to fit extractors. I need to find out if the two aims are mutually exclusive.

The only hope I think is that maybe the extra cat was added to satisfy the more stringent European regulations and that in 2009 the Australian emission control regs were not so strict. Then of course I need to work out whether modifying the car in this way would be legal anyway and then if it is allowed how to overcome any issues with the ECU.

When I find the answers I will let you know. This might take a while.

What issues are you excepting?

The only issue i had when i fitted mine was it throwing code's cus the ERG valve was blocked off. Simple fix tho.

[oozuk]

monkey wrote:

Mike57 wrote:

Thanks for all the discusson. Given the range of opinions expressed so far I need to do a lot more research on this one.

I don't want to remove any emission control equipment that is required by law. I do want to fit extractors. I need to find out if the two aims are mutually exclusive.

The only hope I think is that maybe the extra cat was added to satisfy the more stringent European regulations and that in 2009 the Australian emission control regs were not so strict. Then of course I need to work out whether modifying the car in this way would be legal anyway and then if it is allowed how to overcome any issues with the ECU.

When I find the answers I will let you know. This might take a while.

What issues are you excepting?

The only issue i had when i fitted mine was it throwing code's cus the ERG valve was blocked off. Simple fix tho.

Arr erm.. it's called "EGR" mate, Exhaust Gas Recirculation

and you can't just " Fit a resister" to the O2 sensor harness and expect the computer to be happy, O2 sensors don't vary resistance of a 5V signal according to exhaust emissions like other engine 5V sensors work, they create there own voltage (In mV) the higher the oxygen content the higher the mV signal back to the ECU, the ones that have 12V to the O2 sensor is purely for heating the O2 sensor for it to reach optimum operating temperature.

[monley]

[royce]

oozuk wrote:

monkey wrote:

Mike57 wrote:

Thanks for all the discusson. Given the range of opinions expressed so far I need to do a lot more research on this one.

I don't want to remove any emission control equipment that is required by law. I do want to fit extractors. I need to find out if the two aims are mutually exclusive.

The only hope I think is that maybe the extra cat was added to satisfy the more stringent European regulations and that in 2009 the Australian emission control regs were not so strict. Then of course I need to work out whether modifying the car in this way would be legal anyway and then if it is allowed how to overcome any issues with the ECU.

When I find the answers I will let you know. This might take a while.

What issues are you excepting?

The only issue i had when i fitted mine was it throwing code's cus the ERG valve was blocked off. Simple fix tho.

Arr erm.. it's called "EGR" mate, Exhaust Gas Recirculation

and you can't just " Fit a resister" to the O2 sensor harness and expect the computer to be happy, O2 sensors don't vary resistance of a 5V signal according to exhaust emissions like other engine 5V sensors work, they create there own voltage (In mV) the higher the oxygen content the higher the mV signal back to the ECU, the ones that have 12V to the O2 sensor is purely for heating the O2 sensor for it to reach optimum operating temperature.

lower voltage = lower oxygen = richer mixture