crcorc

Does anyone know how I tell if my catalytic convertor is plugged? My mileage is getting progressivley worse, all typical tune-up items are in good shape, though I do suspect a bad injector (high resisance rating).

subs1000w

do you have a loss of power?

if so to test remove bolts from ypipe and tie up the conveter then go drive (very very loud) and see if power is back up to normal

Ja[M]z

maybe you should say "clogged" ?


Check for some noise coming from it when you press the gas .

internetautomar

iTrader: (30)

check the temperature difference between inlet and outlet.
or just unbolt it and look through it.

mtnbikeair

iTrader: (4)

Should you be able to look through it?? Both of the cats on my maximas you cant see through... one has 208,000 miles and the other is at like 98,000...

internetautomar

iTrader: (30)

if you look through from the outlet to the inlet you should be able to see through it, or at least see light through it.
after all if you can't see through it how do you expect air to get through?

tripleGmax

iTrader: (8)

if you give it gas, do you feel alot of exhaust comin out the muffler? if not could be clogged or even plugged!

Bobo

A quick test to determine if a cat is shot is to bang on it and if it rattles inside its toast. I'm not sure how much more you would expect out of a cat with 208K on it.

mtnbikeair

iTrader: (4)

Yeah i am going to replace it pretty soon with a magnaflow one... But when i looked thru it all i saw was one dot of light. A dot about the size of a pen...

Jeff92se

iTrader: (82)

That's one way to ruin it also if you aren't carefull. Just unbolt it and peer inside. See though and the honeycomb looks clean = good. Can't see though because it's clogged = bad. If you mileage has been bad for a good amount of time, probably means you burnt up the cat

crcorc

Maybe, like you say, I'll drop the cat and look inside. After all, it has 220,000 km, so the possibility of it being shot is probably pretty good...gotta let it breathe!

Wiking

What does ? that mean; pls give the ohms for all six. They should be about equal, otherwise you've got a inj problem.

That does not take out myriad other problems, tst your sensors.
http://www.cardomain.com/memberpage/748507/9


Bad groundings cause warped signals; here warped spiky cam sensor signal before a addon gnd wire...




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crcorc

It's been a while since I checked, but one was at around 25 ohms, the rest were withinn spec (11-13 ohms). Would one injector with such a high rating be hurting mileage so much?

internetautomar

iTrader: (30)

yes..............

Wiking

so how much is much?

1. if resistance is higher, that injector is going to inject less stuff, if any. So its not delivering 'any' power... But still that one cylinder is doing its compression job for nothin. I would just guess that the main thing u lose is pwr, consumption should not raise very much.

2. if its also leaking, you may check out how much the maximum flow is for your injector. From that, one may try to figure out how much one injector may consume if it is always full open. Then, just guess what the other injectors could be doing... If this is the case, maybe your car behaves like a SAAB on cold morning: pure gas spewed on those brave enough trying to follow...

1+2 still, I would check the easier things first, but definitely one of your injectors does not seem to be ok.