HELP! 2002 Toyota Tundra V8 4WD A/T
- Thread starter Zach_795
- Start date
edyvw
$50 site donor 2025
TRQ "performance" coils. Go back to OE.
Why were coils replaced in the first place? I'd rather have high mileage OEM unless one is credibly believed to be failing over aftermarket anything.
That said, the coils are probably not at fault here unless you start seeing more misfires. Does Toyota allow access to misfire counts??
That said, the coils are probably not at fault here unless you start seeing more misfires. Does Toyota allow access to misfire counts??
It doesn't matter, it would be interesting to see counts (NOT codes) to see if one or two cylinders are racking up counts consistently. It takes a certain number of counts to trip a code.
Still, I'd look at MAF first and fuel trims might be interesting
And I was having a senior moment thinking I'd never looked for counts on a Toy but just last week I did on an '08 Tundra.
So yeah, it's there either under Mode 6, onboard monitoring, or my Xtool buries it in PCM data.
Again, not sure this will unlock answers for OP but good to know how to get there
So yeah, it's there either under Mode 6, onboard monitoring, or my Xtool buries it in PCM data.
Again, not sure this will unlock answers for OP but good to know how to get there
These are the headers I got
I will clean the maf today and see if anything changes
My codes reader is the $30 one from Walmart so I can see the live data on fuel trims IAT and pounds of air consumed etc but there’s no graphs or way to save it
I will clean the maf today and see if anything changes
My codes reader is the $30 one from Walmart so I can see the live data on fuel trims IAT and pounds of air consumed etc but there’s no graphs or way to save it
Headers change the torque output profile. Short tube headers open up the exhaust for high rpm gains but sacrifice low rpm torque. And I will add, notable high rpm gains also come at a notable sacrifice of low rpm torque. This would be my first leaning.
How much of a difference are the headers you installed vs what came off? Those don’t look very different from what I had on my 2006 tundra, though i bought it used so idk if mine was stock or not.
How much of a difference are the headers you installed vs what came off? Those don’t look very different from what I had on my 2006 tundra, though i bought it used so idk if mine was stock or not.
Not doubting the diagnosis, but I have seen people want to replace the 2UZ-FE manifolds due to the sound heard inside the truck. Turns out the steering shaft seal had failed. Replace it and back to quiet in the cabin.
I've built and worked on too many cars, motorcycles, and racing vehicles to count. Tested all sorts of exhaust configurations.
As I said, likely your headers are the reason for the reduced power output in the rev-range you're experiencing.
As I said, likely your headers are the reason for the reduced power output in the rev-range you're experiencing.
The problem ended up being the upstream driver side o2 sensor, bank 1 sensor 1. 8 hours into my 12 hour drive today the codes finally popped for it. P0300, P0130, and P0133. Stopped at an advance and got a brand new Denso, changed it in the parking lot. Truck drove perfectly for the last 4 hours back home.
