Help. Diagnosis

I have an 03 Tundra, with a 4.7 l. It's got 190,000 miles on the odometer. It has the weirdest issue. When I drive around town, normal stop and go traffic. Everything is fine. When I put it under load, such as going up a hill, it has a low end rattle. It's sort of sounds like knocking, but I don't think it is. When I drive it on the highway or at a constant speed above 60 km/h, for more than about 10 minutes, and then turn it off and let it sit, and then restart it, it will throw a huge cloud of blue smoke. It's like it's burning oil when it restarts after it runs down the highway. But it's not noticeably burning oil in normal day-to-day driving. I've had two mechanics tell me to replace the motor, and one thinks it can be rebuilt. Any thoughts?

 

Just a check because it's a known issue, do you keep loosing power steering fluid? The steering air control valve can go bad and cause smoke on startup issues by letting power steering fluid in the intake but I'm not sure it could be causing your other issues.

 

Interesting. Thanks for getting back to me. Would this issue cause a residue buildup inside the throttle body(?)/manifold(?) air intake?

 

We need to know what drivetrain your truck has RE: rattle. 2WD or 4WD?

 

Potentially. Test procedure is easy. Check this reply: https://www.tundras.com/threads/valve-seals.113823/#post-2932057

Also, if you haven't read it yet, check this thread: https://www.tundras.com/threads/so-you-wanna-buy-just-bought-a-1st-gen-tundra-eh.115928/

 

Ok. Truck is automatic, RWD.

Thanks for the links. I'll get to testing.

 

Ok, thanks for that info. It's pretty important.

Your truck is an '03, so it shouldn't be impacted by the TSB for the 2WD tranny crossmember.

Strain/struggling under load up hills ... I'm thinking combustion issue, like bad plugs, or you've got a bad coil pack, or you're not getting enough fuel (which would be a fuel pump problem, not the fuel filter, the problem is virtually never the fuel filter).

I'm going to ask some follow-up questions. Some probably aren't going to make sense, please answer anyway.

Have you ever replaced any of the following parts recently, and if yes, which?: Fuel pump. Coil pack(s). Spark plugs. Anything else related to fuel/spark, such as relays etc.?

If you replaced any of those parts, where'd you buy them?

Is the check engine light on? Have you scanned for any pending codes, or set codes? (If there are codes, please share. Any local auto parts chain will scan for free)

When was the last time you installed new spark plugs, or last time you've seen the condition of your spark plugs, how many miles ago?

Do you live in an area where mice are a thing? Mice are actively nesting this time of year especially in cold-weather areas up north, and in dry climate areas down south/southwest. Also, do you park outdoors regularly, overnight?

Is this a recent thing, like since your last gas fill-up, or has it been going on across a few tanks now? Like, I got some bad gas at a local grocery store a few months back and threw a knock sensor code. It was totally the gas, it went away after a bottle of Seafoam and a fresh tank of gas.