2003 Avalon Interference Engine???

[hughesar]

Is the 2003 Avalon an interference engine? Will there be any engine damage in the event of a timing belt failure? Thanks.

[toyomoho]

If 1MZ-FE, then no.

[hughesar]

The engine code is 1MZ-FE.

Does it matter that this engine is VVT-i

[new echo owner]

It shouldn't matter whether it is VVT-i or not; it changes the valve timing on the intake cam, but won't affect the clearance between the valves and the pistons, in the event if the timing belt breaks.

N.E.O.

[hughesar]

The dealer says that if the timing belt breaks with engine at idle no damage would occur to the valves.

However, dealer says if the timing belt breaks at highway speeds, that more than likely, valve damage would occur.

How is this so??????

[new echo owner]

They are probably referring to the possibility of parts coming together if the engine is running at a very high speed. It is possible, however, it has to be at the upper end of the rpm range, like 4000 rpm or above, then that is only a possibility, not necessarily the case each time. At high rpm, the parts do 'stretch', not an excessive amount but sometimes the amount of the 'stretch' would be enough for them to come in contact.

N.E.O.

[silverxls]

the dealer wants to put a timing belt in it and make some bucks. however, you should replace it at 90 to 100k anyway, even if it wont ruin the engine, it's no fun being stranded somewhere.

[toyo_tech02]

non interferance engine, belt does need to be replaced every 90k miles.

[ckelloggjr]

Is there a good (free) instruction guide for DIY timing belt change?

[OpticNerve]

My Haynes manual is pretty doggy eared and I have done things like brakes, MAF sensor cleaning, OCV replacement and rear stable bar bushing replacement. I don't think I am ready for a timing belt replacement, and I did see it done on my Avalon at 107750. Took the better part of three hours from someone who had a lot of experience. You got to get that timing mark right on or you won't be happy. I wish I had passed on changing the water pump and idle pulley done at the same time.

[84Cressida]

I can't think of any Toyota engines that aren't non-interferance. Now Hondas....