Odyssey Won't Start...sometimes

I have a 2001 Honda Odyssey that doesn’t start sometimes - mostly when it’s really cold but not exclusively. It doesn’t seem to matter if the gas tank is full or empty.



It turns over fine and will catch and the die multiple times. There is sometimes a large “clunk” while it is turning over and all the lights will go off and then it will start turning over again.



It can take a minute to 15 minutes to start when it isn’t starting but about half the time, it start right up. This is only in the morning, once it’s going for the day, it works.



126,000 miles, timing belt changed a couple of years ago. Any ideas?

The clunk might be a backfire. When was the last time you replaced spark plugs? Air filter? Fuel filter?

First guess is old and worn out spark plugs. If not plugs, then partially clogged fuel filter, or a weak and/or failing fuel pump.

How is the maintenance on this Odyssey, like tune ups and such…

The air filter is new. I was going to change spark plugs today since they haven’t been done in a long time.

Yes, always start with basic maintenance.

You can find out something of the possibility of a fuel pump issue if you prime it up before trying to start. To prime it keep turning the key on-off-on-off about 7-10 times before you crank it over. The “on” point would be just before cranking when all of the dash lights come on. Each time you do it, you should hear a muffled 2-3 second hum from behind or underneath.

If that works then I’d focus on a fuel issue. If not, I’d start by looking elsewhere - like in the ignition system.

It gets regular oil changes and I did the big timing belt and everything that goes with the tune up at 105,000.
I (meaning my dad) change the air filters and flush the transmission fluid about once a year or two.