Pain in the ar$e ba$###d Lamda sensor.
 

I tried to fit my prodrive cat this afternoon, shouldn't take too long I thought, what a mistake that was.

After taking off the top mount, I found the heatshield was fastened with around a dozen bolts!:mad: Kept my cool and unbolted the cat from the turbo and the centre section.

Next job was to take the lamba sensor out, no problem I thought I'll use my lamda socket. Would it move? would it hell!! I have soaked it in WD40, heated it with a blow torch until it was bright red and nothing:mad:

I've left it soaking in WD40 for the night. Has anyone got any suggestions to get this damn thing out? It's got to the point where the corners are starting to round over.

Cheers, Rich.

Did one a couple of weeks ago(or at least one of the local guys did, but I used the same technique on my lambda a year or so ago) 7/8th's spanner and a copper mallet, came out in no time. Also, how amny bolts on the heatshield - surely it should only be 2!:eek:

WD40 isn't that great either, try duck oil for seized bolts etc.

Cheers, I've got AF spanners there so I'll give that a go.

The turbo heatsheild is riddled with bolts, approx 3 to the right, 3 to the left and 2 underneath! One sheared clean off but I'm not that worry due to the quantity that are there

I helped put a Spec C back together a couple of weeks ago and had my heatshield off last week, both only had 2 bolts:?

Still couldn't get the sensor out so I have unplugged it and left it in the old cat. I bought a new bosch universal one for the sports cat.

The heatshield wouldn't fit around the new PPP cat, so I had to drill out the rivets and split off the lower half of the heatshield. Even then it wouldn't fit so out come the blowtorch for some fettling. After I finish the top half of the shield only needed 2 bolts to fit it back on.

What car is it you have. Just that I know you can't use universal sensors in a newage, not sure what the score is for classics:?

We had one rusted into a downpipe on an STi 7 here, I clamped the lambda sensor into a bench vice and twisted the downpipe, it came out after a while and after cleaning the threads we managed to even fit it back into the new downpipe. :D

It's a 04 Sti, fitted the sensor and checked the output with the laptop and all is ok:thumb:

One hell of a difference having the PPP cat, you can hear the turbo spin up alot louder!

That's interesting as I have been led to believe that the denso sensor produced a pseudo wideband signal that is interpretted by the ECU as such. A universal sensor can't reproduce the output. If it can be made to work effectively with a cheaper bosch sensor then I'd be over the moon as the best price I've seen for this sensor is £190:eek:

I've got a decat up-pipe in the garage, although I'm thinking about getting a matched set of headers and up-pipe having seen the state of my headers when the car was on a ramp last week. I've also been looking at some 100 cel sports cats. The rear cat had already found it's way into the bin:D

I thought the denso sensor was the first o2 sensor after the airbox (that i call a maf). The o2 sensor I replaced was in the exhaust after the CAT. The bosch item cost me £46 from a local motor factor.

Right that explains it. The MAF is the MAF. The one called the O2 sensor is in the headers on bugeyes and in the downpipe just after the turbo on blobs and later. In the exhaust after the second cat is the lambda sensor. The rear one is a check sensor, whilst the front O2 sensor is the loop that manages the lambda ratio in conjunction with the MAF creating a closed loop system - or at least that's how I understand it works.

The 2 lambda/O2 sensors throw different fault codes:?

I'll confuse you a little more now then!!

On my STi there is only one lamda sensor from the turbo all the way to the tailpipe and this is installed where the second cat would normally be. There is no pre cat/post turbo sensor.

Yes I am well and truly confused now because you should have a total of three sensors in the exhaust. The EGT sensor in the up-pipe although this was deleted on STIs, one turbo in the manifold(headers) on a bugeye and one where yours is. The only way I can see it working is if the sensor has been mapped out somehow.

Here's the overview from the workshop manual:?

http://img.photobucket.com/albums/v5...ionControl.jpg

I've got an 03 STI and that's only got 1 sensor in the exhaust and like rsedwards said it's in the second cat.
I'm replacing my cats with a prodrive sports cat tomorrow. I'm hoping I won't come across any major problems.
When I bought the car nearly a year ago it had a full decat exhaust with a massive tailpipe, which allthough it sounded awesome, was a little to loud as I do a lot of driving. So I bought a prodrive back box (new) and some standard cats of ebay (mainly because i had to put it through it's MOT). I've now got the prodrive sports cat, decat second pipe and straight through centre section without the deresinater.
I'm hoping that once fitted the car will sound a lot better.
Reference the heat shield and the screws, mine's the same. I had the intercooler off and the heat shield and checked I wasn't going to have any problems undoing any of the nuts and bolts off the turbo/downpipe. When I tried to undo one of the screws it just sheered off. The bottom half of the heatshield had allready been removed from mine so I didn't have as many screws, I think I had 4 to remove. I've got some new screws to replace the cheap crappy ones that where fitted.

You have a similar setup as me, it pops and bangs slightly but you can't here it in the car. The 2 lower bolts where the cat joins the turbo were a bit of a pain due to the clearance.

Done, and your not kidding about the lower screws on the turbo. Especially the bottom one!! I think it took me about an hour just to screw the bugger in!! I really had to beast myself on that one. Only being able to turn the nut a fraction at a time was made worse by the fact I was reaching upwards!
I've been out for a little drive to bed it in. The volume isn't that much different but it has a deeper growl to it now. The popping is more noticable now as well.
It took me about 3 hours to do in total, a lot of that time was spent messing around with the bottom nut.
Right then, whats next? lol

Oh yea, I havent re fitted the upper heat shield yet. Like you said it doesn't fit and needs a bit of alteration.