00 Sienna Misfiring

Dude, I'm telling you, look to the coils. For every bad injector on a 1MZFE from around your model year, we see 500 bad coils. No joke.

Think. For any cleaner to be effective, you must still have a little flow through the injector. If it's really clogged, no amount of fuel additive is going to remove the clog.

ok, I have a multi meter at home, what's the best way to trouble shoot the coils. I can't keep making trips to autozone for test reads

I believe the Sienna has 3 coils. Take measurements on all 3 coils, The bad one will differ from the 2 good ones.

If the coils are interchangeable, why not swap two coils and see if the misfire moves to another cylinder....

Nirav

If you are into fixing your own car (as you are, for which you should be given credit) you should grab one of those obd2 code readers. You can get a little cheesy one for 20 bucks. Makes diag processes like what you are going through much much easier.

There is a wide variety of code readers out there. Look on eBay for examples which for the least sophisticated can be $30. The best can cost well over $500.

You are making this much harder than it needs to be. Why not measure the resistance of the coils (take a guess and try a variety of pins)?... as long as use the same pins (or test a variety of pin combinarions) on all 3 coils, if you find that one coil is different, it's a good chance you've found the bad part. Coils are generally EASY to swap - so you could potentially just drive to autozone, start swapping coils and pulling codes without ever leaving the parking lot.

The cost of a dealer diagnosis (typically 60-100 bucks around here in Chicagoland) will pay for your code-reader.

Did you already listen to the injectors to make sure they are firing consistently/evenly?

Nirav

The injectors sound just fine, I will put a multi meter to the coils tonight. The Hayes manual I have gives a resistance measure for cold and hot coils.

Measuring primary and secondary winding resistance is NOT sufficient. To think so fails to consider internal insulation break down when the core becomes hot, fails to consider arcing from the secondary windings to ground, fails to consider insulation break down of the spark plug cap which does occur when you consider the entire plug cap and spark plug are closely surrounded by a grounded metal tube.

So if one out of the three coils measures differently, you are saying that is not sufficient to pinpoint that as a faulty coil?

Again - I'm not very familiar with the Toyota V6 family, but are the coils interchangeable?

Nirav

they are interchangeable

FYI, the problem was 4 out of 6 injectors clogged, not electrical at all

"" wrote: > Noticing the engine light on, I took my sienna to autozone for > diagnosis. They informed me that there were multiple engine > misfires > and to change the plugs. I changed cylinders 2,4,6,and > 5...but am > having a hard time with 1 & 3 as they are against the firewall > under > the intakes. Any suggestions to get to them? > > Chris

Chris what was the innitial fault code found?

Joanne MH