clogged cat converter?

[big_buh-gina]

how can you tell if your cat coverter is clogged? i think mine is stock. do i just assume it's clogged since the truck is 22 years old?

thanks!

ben

1987 4runner 4cyl. 2.4L, 5spd, efi, 238,000 miles.

[sb5walker]

The "right" way: pressure-test before & after the cat. Shops drill small test holes for this; can sometimes use the O2 sensor ports.

What you can do:

Have someone rev the motor a few times and feel the exhaust stream. There should be distinct blasts of exhaust when the motor is revved (with a delay of a second or so). If the cat is badly clogged, it will smooth out the flow - there won't be distinct blasts of exhaust.

Or, you can pull the O2 sensor and see if the idle speed jumps up, or see if it seems like all the exhaust is trying to exit the sensor hole (be careful - the exhaust that far forward is hot enough to burn).

Or, you can pull off the cat and shine a light into one end and see how much light comes out the other end - should come through quite clearly.

Or, just figure if it's that old it's probably clogged (and probably not working all that well), and just replace it with a $100 direct-fit magnaflow off ebay. (You'll need two gaskets and possibly new bolts, too). If the old one was clogged, you'll feel some extra power and see an improvement in gas mileage (not to mention, the emissions #s should go down).

[fourwd1]

Originally Posted by big_buh-gina

how can you tell if your cat coverter is clogged? i think mine is stock. do i just assume it's clogged since the truck is 22 years old?

thanks!

ben

1987 4runner 4cyl. 2.4L, 5spd, efi, 238,000 miles.

That's a pretty good assumption.

One symptom is a loss of power, especially going uphill. If you find you need a lower gear to climb a hill than you used to, could be the cat.

[wolfgangdieter]

I just replaced the one on my '85 PU - had 111k mles. Was not cloughed at all but the end caps were rusted badly and leaked. $85 off ebay with shipping from place in TX. Ground off old nuts and installed with new stainless steel bolts/nuts in 1/2 hour.

[big_buh-gina]

Is this thing still on?

well, this truck ended up sitting for a while, but i'm back in it now and plan on installing a new catalytic converter this weekend. I got a direct fit Walker #16360 which came with no instructions. my only question about this is which end should be facing the front of the truck? on the inside of one side, the number 493 is visible. on the other side, the number inside says 493A.

any idea which way this thing is supposed to go on? or if it even matters?

thanks,

ben

[fourwd1]

Usually there is an arrow --> stamped somewhere on it that indicates the direction of air flow.