Viggen Catalyst Replacement - Saab Forums

dublindaly · #1 10-24-2007, 02:38 PM

On my 2000 Viggen, I have just found out the front cat that connects to the Turbo needs to be replaced. I was going to try bypassing the Cat by piping the Turbo into the second cat but don't know if this will impact emissions, power or anything else.
any body have any ideas?

Right now the car is doing 13 secs to 60mph and struggles to pass 90mph

Roto · #2 10-25-2007, 09:49 AM

I wouldn't bypass the cat as it will set off a check engine light...either get it replaced ot look at a performance downpipe...I have a genuinesaab downpipe and it's a well designed piece...

dublindaly · #3 10-30-2007, 03:37 PM

Where could I get the performance down pipe and is this fitted to the Turbo? Do you know if it would effect emissions when tested?

Cheers.

Roto · #4 10-30-2007, 10:11 PM

if you're in the US http://www.genuinesaab.com/catalog/p...roducts_id=403

That is the downpipe that I have and it connects to the turbo and doesn't affect emissions. (Unless you're in Cali than I'd give genuinesaab a call and find out if it's CARB legal)

rfox0100 · #5 10-31-2007, 12:54 PM

I absolutely agree with Roto. I don't have a downpipe on my saab yet, but I have a 94 RX-7 twin-turbo and the downpipe on that made a HUGE difference. If your pre-cat is shot then go ahead and replace it with the downpipe, rather than pay just as much money (if not more)for another piece of exhaust restricting junk.

BTW: Pre-cats exist for emissions tests only. They heat up much faster than the larger catalytic converter so they start to function quicker. In order to pass California's stringent emission laws, manufacturers beganputting small pre-cats as close to the engine block as possible. Most states emission laws allow for the engine to warm up to operating temps before the emissions are checked, but not California, they check on a cold start. It is generally easier for a manufacturer to just keep everything the same so all cars get a pre-cat and the consumer pays for it. I removed my pre-cat from my mazda and easily pass emmisions in PA.

Roto · #6 10-31-2007, 10:33 PM

Where in PA are you from?

dublindaly · #7 11-01-2007, 04:09 PM

Thanks for all the info. I'm in Ireland & wouldn't think the emission laws are as tight as Calafornia. I got a second opinion an their is a fault PO400 logged in the ECU but the engine management isn't on and the emission readings are clear. So not sure if the Catalyst is gone or if it's over worked and the emissions are
OK because of that. Need to get another Saab dealer to diagnoise before I strip out the Cat when I can't get anyone to standover what I'm being told.

Thanks again lads & I think I might go for the performance downpipe anyway.