Hey Guys, just wanted to see what people thought about decatting the 1.9 mjet, anyone done it and if so does the cat have any type of electrical sensors e.g. oxygen sensor going to it, any advice would be much appreciated


cheeers

i have done it on my 1.9 mjet, there are no sensors that are affected from removing the cat. Turbo spools up faster and few bhp gains are as a result. Still passes emissions due to DPF on downpipe (know this becuase had mot last week) removal of DPF will effect emissions light though.

Yer i heard that about the turbo, ahh thats good then that was gonna be my next question with the emissions, so if i did a set up with taking the cat out the mid box and replacing both with piping would that still be ok on emissions? and have you kept the standard back box on it?

but not every 1.9 mjet has a DPF so be weary

Robert1031 said:

i have done it on my 1.9 mjet, there are no sensors that are affected from removing the cat. Turbo spools up faster and few bhp gains are as a result. Still passes emissions due to DPF on downpipe (know this becuase had mot last week) removal of DPF will effect emissions light though.

Click to expand...

Describe the bit you have removed?

The cat has a Lambda sensor in and is in the turbo down pipe.

actually thinking about it, i think the cat is in the downpipe, not under the car, if its the part i am thinking of the part you have removed is just an extra silencer.

I thought the CAT on the T-jet & M-jet was connected to the manifold? I was told this when the exhaust place had a look at it?

Reece

reecey_p said:

I thought the CAT on the T-jet & M-jet was connected to the manifold? I was told this when the exhaust place had a look at it?

Reece

Click to expand...

Correct Its straight after the turbo on the downpipe. Order goes manifold, turbo, cat.

the turbo is connected to manifold and cat just underneath it

I'm guessing with DPF soon after on a DPF'd car.

Wonder if where some users get a DPF we get that odd looking centre box post flexi.

Yep, DPF is fitted in place of the centre catalyst box on those with it. Downpipe 'cat' is a pre-cat.

seems to be some confusion, i had my cat taken out like i said earlier along with my mid silencer box or what ever you wanna call it. The cat was after the flexipipe but before silencer.

I was told the downpipe either contains a DPF or a pre CAT, mine has DPF here but im getting that took out soon.

Is this correct?

according to Eper the box in the downpipe is a silencer catalized, and the box after the flexi pipe is a ANTIPARTICUL.FILT. which by my translation would mean DPF (diesel particulate filter)

alexh365 said:

Describe the bit you have removed?

The cat has a Lambda sensor in and is in the turbo down pipe.

Click to expand...

Does anyone have this fitted to their mjet?

Robert1031 said:

seems to be some confusion, i had my cat taken out like i said earlier along with my mid silencer box or what ever you wanna call it. The cat was after the flexipipe but before silencer.

I was told the downpipe either contains a DPF or a pre CAT, mine has DPF here but im getting that took out soon.

Is this correct?

Click to expand...

According to Eper, there does seem to be 2. The second CAT is not monitered by Lambda sensors and therefore would have little difference on engine management apart from a drop in back pressure. You have removed a silencer by the looks of it

The DPF will be a little different, and it will require some work on the ECU unless you want the EML on all the time.

two things came out of my exhuast though, one was silencer and other was CAT im sure

Robert1031 said:

Does anyone have this fitted to their mjet?

Click to expand...

I have one on my car.

toas1372 said:

I have one on my car.

Click to expand...

Any good? Wat difference does it make?

alexh365 said:

Describe the bit you have removed?

The cat has a Lambda sensor in and is in the turbo down pipe.

Click to expand...

I have a straight through pipe after the flexi-pipe and i gutted the pre-cat from the picture above on the right. No ECU light came on because the sonsor is before the cat.

It's not very loud, but you definately feel a difference.

hbucur said:

I have a straight through pipe after the flexi-pipe and i gutted the pre-cat from the picture above on the right. No ECU light came on because the sonsor is before the cat.

It's not very loud, but you definately feel a difference.

Click to expand...

You mean you've opened it, destroyed the inner contents and then welded it back up?