With almost 160,000 miles on my car, I figured I would ask this question. I noticed the wear on my engine after driving my friend's 99 4-cyl Camry. Her car jumped off the line much more than my car. Also, her engine sounded like it was laboring much less when accelerating (Mine groans a bit; louder).

I know our engines are supposed to have about the same power output, and I am confident that Toyota engines can keep most of their power after high miles. My car has NEVER had a valve lash adjustment or a timing adjustment. Are these adjustments a requirement for my car? Would they improve throttle response? Here is a rundown of my car's "personality":

* Uses less than a quart of oil after 2,000 miles.
* Transmission has pink fluid and no major issues (though it is not nearly as smooth shifting as my friend's)
* Mileage approaches 30mpg on the highway.
* Seems to idle without a hickup (though it has the common shaking issue when stopped in Drive).
* No Check Engine Light.
* I slight smell comes into the car when the engine is laboring harder (sulfur?).
* Distributer was replaced with a rebuild last winter after I had the cold/damp ignition failures.
* I noticed the degredation of "smoothness" a little over a year ago.

Some days, my car seems to accelerate better than others. The other day, it struggled a bit while accelerating onto the highway. I pushed the gas down harder until it downshifted. At this point, it started to pick up (while belching out a Celica-like roar), but only because it was at 5000 RPM. Normally, it would do better without downshifting.

I want to keep this car longer since it's been so good to me, but it just doesn't run as smooth as it used to. People used to argue with me saying it was a V6. It accelerated well and was virtually silent. If I can get it close to that point without buying a new engine, then I'll definately keep the car (Everything else is immaculate). Thanks for any help that may be offered!

-Andy

I forgot to mention that my engine chatters much more than it used to when cold. I think I can notice a slight chatter when the RPMs are climbing past 4000 after the car has warmed up. That's why I thought of the valve lash issue.

Andy,

My wife and I own both a 94 4 cylinder 5SFE engine and a 98 4 cylinder 5SFE engine. The 92-96 generation porduces 125 horsepower. The 97-02 generation has a reworked exhaust manufold, a different computer and a different transmission; it produces 133 horsepower with these changes. When I go from the 94 to the 98 I also notice the difference in power between the two and both cars have around 70,000 miles. That said, I would just check the basics. Change the plugs if they have more than 60,000 miles on them. Check the air filter; when was the last time it was changed? The manual calls for it to be changed every 30,000 miles although personally I feel that is a bit excessive unless you drive in real dusty conditions. A good fuel injector cleaner like Chevron with Techron in the tank is also a cheap and good investment. In addition, I would also try cleaning out the throttle body. There were some good instructions in a recent post here on how to do it. Do a search. If you still don't feel a difference, then I would take it to a professional.

Mike

Andy,

Here's a link with instructions on cleaning the throttle body:

http://www.4x4wire.com/toyota/maintenance/30_V6/throttle-body

Mike

Thanks for the info Mike,

I've recently changed the air filter and the plugs (platinum tipped). I also add fuel cleaner every month. I haven't tried cleaning the throttle body, so will definately try that. Do you think a slight exhaust leak would affect performance (due to less back pressure)? I wonder if I'm just imagining that there is less power due to the extra noise the engine puts out (ie thinking that I have the pedal pushed harder than I really do because of the noise).

I definately learned something new today. I never knew the HP was increased on the late 90's Camrys.

Andy,

I really don't think the slight exhaust leak would affect performance. The buzzing you are hearing could be from the sheet metal around the exhaust system. They loosen up with age and rust and can create an annoying vibration. Remember, at 158,000 miles I'm sure you have lost a few horsepower due to normal wear of the internals.

Mike

Mike, your link is broken.

http://www.4x4wire.com/toyota/maintenance/30_V6/throttle_body/

Still need that forward slash at the end I guess.... :)

At 160,000 miles, you might want to consider going with a full timing set change as opposed to just the belt.

Rule of thumb is to change the timing belt every 80,000 miles. But from my past experience, I've went with a full timing set (including tensioners). I also took the liberty of changing the water pump as well.

You might not have to worry about the water pump, but I did that for my 88 Camry I4 (3SFE) since I was already down in there.

Good luck with the car...

Lucas transmission fix as preventative maintenance will quiet the transmission and smooth out the shifting without harming anything.
Redline complete fuel system treatement will bring back the power. You should then use it continually for 10 - 20k miles (1 bottle/ 100 gallons).
Read their tech sheet
http://www.redlineoil.com/products_fueladditives.asp