2000 Toyota Tundra 4.7 (Putting)

4.7 V8 I changed ignition coils and plugs but running rough. 169000 miles, starts great, timing belt replaced at 123000 miles, o2 sensors are going bad but told that isn't issue. Can only say it Putts until up to speed I need ideas....Thx

 

Putting. Like a vibration? Lack of power? Roughness of acceleration?

 

Cold air intake so Air filter has been cleaned, oil change and filter 725 miles ago. Not a vibration, noticeable putt, putt, putt at exhaust. Acceleration okay and full highway speed good with no noticeable putt.

 

O2 Censor code, that is it

 

Thought maybe Vac leak somewhere? Don't hear it or see it.

 

Clogged cat or muffler?

 

Will look at and get back to ya...Thx

 

You can spray starting fluid on vacuum hoses while its running and listen for a change. Sometime a misfire will give a putt putt sound, but that’ll usually throw a code.

 

Was it happening before the coil/spark swap? If NO, you didn't buy your parts on scAmazon or fleaBay, did you?

Likewise, did you go with OEM coils? Exactly which plugs did you buy?

 

I second all this stuff. Cheap coils are junk need denso. Amazon could sell you cheap Chinese plugs labeled as name brand. Only buy name brand from a reliable site like Rockauto.

 

Googled it and here's what one person says;

"Most of the time it is caused by a worn out timing belt or a clogged catalytic converter. It can also be caused by a failure int he transmission. I usually check the timing belt visually and then check he fuel pressure as well as the exhaust back pressure to see what is causing the failure.Sep 28, 2016"

 

If your O2 sensors are bad, they cause a run rich situation by default. The rich running can burn up your catalytic converters. If it sounds muffled and struggles to breathe, I would be suspicious of this. Sometimes you’ll get a rotten egg smell from the exhaust. Also make sure the maf is clean if your running an oiled air filter (like K&N). The filter can be overly oiled and it creates residue on the MAF sensor. Good luck with the diagnosis and repair sir, keep us in the loop!