99 Sienna can't start when it's hot out and after running for a while

[Frank_Van]

3 weeks ago, when I tried to start the van, I smelled something burning. But when I tried again, it started. And there's no problem after that.

However, last week, my van started to behave strange -
When it's hot out (Texas is warm now), after driving about 20m, I park the van, the hand brake light comes up even though I didn't hand brake. After that, I can't re-start. Sometimes, when I put the handle to parking, even if I don't turn the van off, it turns off by itself.

I have to wait when it's dark and cool, then I can start it again.

Took it to dealer, they can't reproduce. I think they didn't drive long enough.

Has anyone seen this problem before?

Experts, please help!

[Doug Tatham]

I'm a weekend mechanic so take this with a grain of salt. What you described sounds like an electrical problem. Resistance changes with temperature and if something is running on the edge, higher temps can push it over. Take it to autozone, discount autoparts or some other autostore and they'll do a charging system check for you for free. My thought is that it may be the voltage regulator. It's generally part of the alternator these days. The brake light comes on when the key is in the on position and the engine isn't running. Are you sure that when the light came on your engine hadn't died? The not so pleasant possibility is that you have a major problem with the electrical system, something is shorting out and killing the engine and making the light come on.

[Frank_Van]

Thank you, Doug!

I took the van to a nearby autozone. They checked the battery and alternator charging system, everything works as expected.

If the handbreak light is on when shifting the gear from D to N or from D to P after driving for 30 minutes or so under hot weather, the van won't start after turning off the engine.


Do you think that we need to clean the idle stabilizer?

Thanks,
Frank