Bad fuel economy and slugging acceleration 2007 4.0l v6 Tacoma

Hey fellow taco lovers. I'm looking for some insight into a problem I'm stumped on.

I bought my truck 2 years ago with 316xxx on it blew the motor at 325xxx

swapped a 2011 motor in and ever since then i've been getting about 250kms per tank compared to the 400-450 i used to get. The truck also has a very sluggish acceleration and feels like its "choking"/under very heavy load like towing.

I have p0420 for bad cats, I bought it like this and it was fine.


This problem goes away temporarily if I disconnect the battery for 15 or so minutes to reset the ECU, but the problem comes back after a few restarts of the engine.

I have tried running seafoam through many times. I have cleaned the MAF, put a new air filter in new trans fluid and new plugs with no luck. Also new alternator last fall. seemed a little worse after I replaced that.

Can anyone chime in on this?? I am completely lost I can also provide some videos of it chugging vs after I reset the codes tomorrow.

 

I'd want to check exhaust backpressure, I'm thinking you may have a plugged cat.

 

Sounds right to me, choked off it is.

 

I have check and the exhaust is clear no blockage. However it does still feel like it’s choking. And the problem completely goes away for the first start or two after disconnecting the battery for 15 or so. Could this be an AF MIX problem?

 

Are you sure P0420 is your only code?
And can you tell us what you fuel trims are when this is happening?

 

sounds like clogged cats, or the cats coming apart clogging somewhere in the exhaust system.

 

You can't quit ignoring the truck telling you it has an issue by temporarily erasing the code if it keeps coming back. You have failing cats that has been purring at you and now meowed for the last time. It's not going to cough up the fur ball this time.