Car Shakes during IDLE

[GeoffreyVB]

I've noticed a similar issue with my Yaris. It's got what I would discribe as a shutter at idle it seems completely random, it's almost as if it just misses a cylinder sometimes. I got a OBD2 reader and was able to see that the vacuum does drop at the same time these little studders occur.
It's got about 160k miles on it, I'm thinking I'll try cleaning the MAF and I could change plugs? But it wasn't all that long ago I did that.

It's recently also started doing it other times than idle too. I tried. Checking the air fuel ratio with the OBD2 but it sounds like that might just give the target?

[rayfloyd170]

Originally Posted by GeoffreyVB

I've noticed a similar issue with my Yaris. It's got what I would discribe as a shutter at idle it seems completely random, it's almost as if it just misses a cylinder sometimes. I got a OBD2 reader and was able to see that the vacuum does drop at the same time these little studders occur.
It's got about 160k miles on it, I'm thinking I'll try cleaning the MAF and I could change plugs? But it wasn't all that long ago I did that.

It's recently also started doing it other times than idle too. I tried. Checking the air fuel ratio with the OBD2 but it sounds like that might just give the target?

Exactly had the same issue for quite a while..

I have cleaned the TB, MAF, PCV and regularly changed oils and filter as well as changed plugs... but the problem is still intermittently there and i learned to lived with it as i heard it is Normal for all Yaris having manual trans...

Anyway, i got nothing to loose and said to myself to try the Gumout regane fuel system cleaner with PEA which i find on the shelf in the store and was surprised to see a big difference..

No more shutter at idle for 1 week now and counting... my wild guess, it could be partially dirty injectors or fuel system lines, i also get ~20% extra mpg...

i know some people confirmed it to be related to the brake booster but with just a few bucks i got nothing to loose here...