Changed catalytic converter - car doesn't feel right

blizeH

Active Member
May 12, 2008
203
0
Hey guys,

I had my cat replaced on the car recently, it sounds a lot better of course, but I'm noticing a couple of other problems too:

1. The car's power seems to have quite greatly reduced. I'm not a fast driver but it seems quite noticeable and annoying, even in casual every day driving.

2. My car used to go into 'limp mode' a lot which I understand is a fairly common problem for VAG diesels around my cars age, but in the last 6 months it's gone into limp mode maybe twice and that's it. By contrast since getting the cat replaced, it's gone into limp mode maybe 10 times just in the last week.

Is there a chance I've got the wrong cat on there now? Or is there some weird thing where maybe because it now doesn't have the hole (well not a hole, more it was a circular thing and only hanging on by the top) that it's causing these problems?

Really confused by it, and sadly I'm almost tempted to get a new car :(
 
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blizeH

Active Member
May 12, 2008
203
0
I believe so, but I'm not sure. Seat quoted me £671 and I paid someone locally about £200 to get it done. So thinking about it, I guess no, it's not genuine :(
 

blizeH

Active Member
May 12, 2008
203
0
But... but... but I just spent £200ish on getting one fitted! :D

God damn.
 

blizeH

Active Member
May 12, 2008
203
0
Okay. This is doing my head in now. Can't even overtake cars doing 30 in a 60 going up a hill for fear that my turbo will cut out!

How much would I be looking at spending to get it changed over so it bypasses the cat? Would it be louder? Less powerful? Loads more emissions? I mean there must be some drawbacks right? :(
 

blizeH

Active Member
May 12, 2008
203
0
Quick bump before I get it removed! (or worse - just buy a new car, eeek!)
 

volvic

It's just water
Jun 28, 2008
791
0
House of Batiatus
since the cat is the last thing you changed, i'd go back to the garage and ask them to take the cat off, and fill the void with a pipe to make it straight through. This shouldnt cost more than £80 for parts and labour at a guess. if this fixes the problem, ask the garage if they'll buy the cat back (you'll lose some money but its your best choice!)
 

blizeH

Active Member
May 12, 2008
203
0
Cheers volvic, that's what I was thinking really. It's going to be a pain but may be my only option right now! If I can get even a tiny bit back on the cat it won't be too bad.

Just wondering also, is the cat causing the problem, or is the fact the whole in the exhaust isn't there any more? Might sound crazy but I do wonder.
 

blizeH

Active Member
May 12, 2008
203
0
Me again (sorry!) - just spoke to the mechanic and he said it's absolutely fine, but he'd recommend I get one myself.

It's a 2003 (52 plate) TDi SE - is there a standard decat pipe I can buy for that, or are they all a bit different? Looking through the actual brochure of cats was a nightmare, so many different ones just for my model! ;_;

Thanks
 

Willie

LCR Track car
Aug 6, 2004
8,939
1
Sunny Scotland
If you were having problems before doing this then there is an underlying issue.
The CAT change might have accentuated this but doubt it the silver bullet.

I'd source the original problem before you start throwing more money at something that sounds like its not the main problem.

Why did you initially have the CAT changed?
 

blizeH

Active Member
May 12, 2008
203
0
Thanks Willie, I think you're right, and looking around a decat is going to cost at least £150, plus maybe £50 fitting, so it's an extra £200 or so!

I changed it because there was a big hole in the cat, like it was just hanging on from the top, think it had been like it for a while but it wasn't too loud/prominent until recently :( But it never went into limp mode even once during the last 8 months or so before I had it changed. Now I put my foot down even a bit up a hill and I feel it going, so have to ease off before it cuts out.
 

blizeH

Active Member
May 12, 2008
203
0
Not sure, is there an easy way to check something like that?

Not sure of the best way to explain it, but if you can imagine the pipe coming from the cat being cut all the way around but hanging just from the top, that was what it was like - not a big hole and not really disintegrated or anything, almost like a clean cut to the top
 

Willie

LCR Track car
Aug 6, 2004
8,939
1
Sunny Scotland
Have you tried the cures for the 1.9 TDI limp mode.

Is it not either a sticking EGR valve, stick fins on the turbo or summat in the inlet manifold?
 

blizeH

Active Member
May 12, 2008
203
0
Could have a go at that thanks Lee, I have no idea how to do it myself but will ask around/some mechanic and go from there!

Willie, thanks for the suggestions, do you know of any guides or anything I could look up for that? Sorry to sound dumb but I don't have a clue unfortunately, I've looked up limp mode before (like a couple of years ago) and tried a few things, but can't remember specifics :(
 

Willie

LCR Track car
Aug 6, 2004
8,939
1
Sunny Scotland
try google search for your fault s and your engine.
My dads van has the same engine and turbo as you, this used to do this but dunno if it still does as haven't driven it in a while.
I searched google for 1.9 TDI limp mode, or summat like that
 

blizeH

Active Member
May 12, 2008
203
0
Many thanks Willie, just looking around now, read quite a few different threads but nothing particularly set in stone, with many different faults (from sensors, to brake lights (what?!) to overboost, to the turbo control valve, to simply revving the hell out of it on a fairly lengthy journey) some I can try, but I'm thinking to get it fixed could be a very costly process.

I'm tempted to stick the money towards a new car, but that sucks because I'd be stitching someone else up then too, whoever buys the thing :(
 
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Faisal

UK's 1st Liquid Yello LCR
May 27, 2008
1,445
0
Most likely at work
its better to fix a problem that your car has rather than sell it for a new one. you learn a lot more - and you will be prepared to tackle problems that your next car further down the line will bring you.

trust me, i went from zero knowledge to some level of competence in this whole car jazz!

hope you get it sorted
 
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