Any way of telling if you have gutted pre-cats?

[weekenny]

Perhaps with VCDS?

Short of dropping the exhaust, is there a way to tell?

Basically my car has a number of mods not listed in the for sale advert from when I got it and I'd like to gut the pre-cats but don't want to drop the exhaust only to find them already done.

Cheers

[MikeFish]

VCDS won't tell you. Does it smoke when cold?

Actually, someone really clever might be able to tell you how to check by looking at o2 levels or something when cold. I'm not that clever.

[Starry]

maybe remove the lambda sense and have a poke around with a coat hanger or similar..

[weekenny]

I did think of that Starry but the sensors are totally seized in there.

[TechNick]

Would there be telltale weld marks, depending on how it's been done?

[weekenny]

Mike I'll check for smoke. Thanks.

Nick if it was a cut and shut then yes but it looks ok on the outside.

[MikeFish]

Mike I'll check for smoke. Thanks.

Nick if it was a cut and shut then yes but it looks ok on the outside.

If you haven't noticed the cloud of smoke already then I'd say you probably still have your pre cats.

[AlexB7RS4]

Most people move the lambda sensor to after the main cat to avoid an error code when cutting the pre cats I believe. Check where your lambda sensor is?

Other than that, smoke test as Mike said.

[Starry]

Mine are gone and i only get smoke occasionally. But they all smoke a bit on start up. Depends on the amount i suppose.

[weekenny]

It has a stage 2 MRC map so the sensors are in the factory places.

[MikeFish]

Ask MRC what other mods they carried out.

[weekenny]

I have the receipt so I know they didn't do it. Also have a K&N that they did not supply and a host of other diy mods that were not in the sale advert.

[Starry]

I'm now sure how this works but if they are mapped out then are they completely of the radar?
If so then unplug them and see if it throws a fault.