girl7

How can you tell if you have a clogged cat?

The car is a little slower than it used to be and my amatuer mechanic friend is going mad trying to figure it out.

No smoke, new plugs and wires and also checking over hoses now...not finding anything.

He suggested it could be a clogged cat, but does not know the symptoms.

Toadman

A clogged cat would be recognizable easily, as the car would suffer SEVERE performance problems because the car cannot "exhale". A clogged cat can glow cherry-red and cause the pre-cat converter to glow as well. Have you checked the Y-Tube connector on top of the turbo intake for cracks? Do you have a boost guage to help ID leaks?

Toadman

We need more info if you want us to help out. What exactly is the car doing that makes it seem broken or clogged cat? What RPM, speed, gear? Does it sputter? Stumble? Sound like a boost leak?

Care to reply? Doctors can't help you if you don't tell them where it hurts.

girl7

The car doesn't sputter...it seems to run relatively smooth, but not as fast. I could never really hear the turbos much...I think because the tires I have on there are REALLY load. The sound like mud tires.

Driving it...it is possible to say there is little to no boost. I was rainy all day so we did get to look under the manifold.

The car did buck a little more today.

It rarely used to do the 3k hesitation unless the air or something else was on. I have an extra gound on there already.

It is still a quick car, just not as quick.

Trexthe3rd

Specify all the mods you have, and the age / mileage on the cat. This info will help put you in the ball park of clogged or not.

technonovice

I has no mods. It is all stock with 100,550 miles. No strange smells yet either. And the power loss did not come gradually. It was instant...all at once...one drive later.

Storm Knight

iTrader: (1)

If it happened all of the sudden, check the boost system for leaks. Check the turbos as well. Mine went out on me when I was driving down a city street. Pushed the gas and the turbos made the sound of an unbridled lawn mower with no boost. Hopefully, the leak is the problem.

At 100k+, I would reccomend replacing the precat with a downpipe. It will drop the temp of the engine bay, and will make your main cat last longer. With that many miles, the temp of the precat can reach 400+ degrees (mine went to 450 by laser thermometer.) It's a realatively simple mod, actually improves the turbo performance due to breathability, give you around 12-15hp more, and drops the engine bay to a reasonable level.

Toadman

Bucking? No black smoke correct, but still check the MAP(Mean Atmospheric Pressure) sensor vacuum line to the sensor on the firewall directly in front of the driver. Little black box on a metal mount and says "Boost sensor"on it. Nice and tight? Remove the plastic intercooler tube and bands and remove/inspect the rubber coupler for the turbo intake on top of the turbos for cracks. Does the car "whoosh" when you stomp on it? Can you borrow a boost/vacuum guage from someone? It will seriously help out.

swarol

I'd strongly recommend replacing all the vacumn lines and getting a boost guage. It's almost impossible to tell if one of the lines is leaking by looking at them. The hose materials are under 100 dollars and can be done by anyone with patience. The boost guage will let you know that the turbos are working correctly, or not, before and after the hoses are done.

My car developed a problem with the secondary turbo (wouldn't kick in) and I replaced the hoses and the problem is fixed. I checked every hose I took off but didn't notice a cracked hose anywhere. However, my car is once again making proper boost so one of them was screwed up.

girl7

MAP sensor hose seems fine. I'll know more when I get my gauge.I'll be looking online tonight for one. Hopefully it is easy to put in.

Any good how to sites for a boost gauge?

I don't hear a whoosh. I heard whoosh from busted y-pipe once in another FD once. No sounds like that.

This is a pain with no gauge.

Storm Knight

iTrader: (1)

It all depends on your desire. I had more people give me advice on the choice of gauges than there were gauges in the area. Mine match the rest of the gauges including the light color. Auto Meter, VDO (heard this is the best,) the list goes on. Try Mazdatrix or do a sort on the name of some of the companies, and you should do well. Just mount it in a place for ease of reading while you are driving (A pillar is where mine is, and I am fine with that, though the one on top of the steering wheel is a nice location too.

Do check the vacuum lines, then check the turbo. Pray that the turbos aern't shot. I have seen rebuilds as much as $2500, and new OEM runs $3900 and change.

Good luck

evot23

iTrader: (17)

I have an extra boost gauge you can use if your aren't ready to buy one yet...just pay for the shipping and I'll send it out to you. Its an apexi that measures in bar so you'll just have to convert.


Let me know.

technonovice

Thanks it may be nice to have it regardless to make sure the one I get works right...

or is there an easy way to test a new one for accuracy?

Oops. I'm in the wrong thread. Thought this was my thread.
Sorry girl7. Did not mean to move in on you. hehe.

But is there a way to test a new gauge for accuracy. I'm not sure that my boost readings will be reliable.

girl7

Keep your paws off! Just kidding...I saw your posts. Thanks for your help earlier.