exhaust/catalytic problems..

HELP...
2000 Tacoma 2WD 3.4 V6 (CALIF) 200,000 miles I changed the bank1 02 sensor which removed check engine light. no chk engne lite on. also changed MAF sensor.

however when I drive down the street all of a sudden no power, give it gas and it wants to go, but no go, ive been told its time to change the cats. anyone deal with this problem?? again it will drive fine then all of a sudden loss of power after few minites at rough idle it will go, getting worse. change cats?? please, thanku

 

If your cats were that bad they should throw a P0420 code. That's what happened to mine when my front cat went bad recently.

 

that happened; changed O2 sensor still major hesitation; anyone experience this with their TAC

 

Not necessarily. ^^^ cars can be sort of stupid sometimes. Especially the older ones.

Your reduction beds within the cats have most likely come loose and are not causing restriction until you give it some throttle which causes the additional force of air to come through the exhaust manifolds ultimately pushing those beds back towards the outlets of the now damaged cat converter(s). A telltale sign of this is that pesky rattling sound that people come in complaining about often.

At that mileage they are typically tired and any sort of lean running condition will finish them off. Sounds like you took care of the cause of said damage, now all you have to do is fix the damage if they are indeed bad.

 

thanku

and this is the reason for backfire or "popping" i believe from my airfilter (very seldom)???

 

How many miles on spark plugs?

 

Possibly. Yes. Disconnect the exhaust before the catalytic converter if you can and run it that way, it will be loud as all he'll, but it will eliminate the possibility of plugged exhaust.

If you are still popping through your intake that indicates a very poor lean running condition. Not something to be taken lightly and should be addressed ASAP if the condition still exists after doing said work to the truck.

If the popping condition exists even after doing that, that popping is huge indication that you are running terribly lean and the destroyed cats are a direct byproduct of said poor running condition. Cats hate excessive heat.

 

@SteveS less than 3k on new plugs...
truk needs new cats, then pass smog, then 4sale....!
thanku all
will keep all updated

 

@12TRDTacoma
thanku sooo much for input
again will keep u upto speed, gonna go with the new cats... in shop tomro

 

No problem. Let us know how it goes.

 

UPDATE... problem seemed to be solved;
NO CATS AT ALL, problem was new MAF n throttle positioning sensor and air fuel ratio sensor all of these together were making my fuel system too rich and out of operating range my mechanic reset all sensors to factory recommended settings truck runs brand new so far so good 100 miles since released from mechanic....

 

Awesome! That mechanic is a keeper. Happy trails!

 

UPDATE... i brought it to get smogged lat week after 230 miles on computer after all codes reset,etc... and faile smog cuz "catalyst" not ready...!!???

 

anyone thoughts???

Gary my mechanic installed new MAF and whole bunch of other parts (see previous post with bill and work performed)...

mechanic and I r shocked smog wont pass,

good news is truck is driving 1000% better, like a brand new truck, zero hesitation, more power, better mpg, etc....

no rattling in cats i did tempature test on cats b4 b4 intake and after exhaust, temps were within factory specs, no rattling or crazy noise...
SUGGESTIONS...????!!!

 

Was the truck cold before the test? If so, drive it to get it hot then idle and do not shut off the engine until the test is complete

 

Maybe you still need new cats?

 

A final update is always the best practice.... Other people may be having similar problems and need to know what the final outcome was with the steps you had taken.. Come on guy...