The intermittent cranking no start Yaris VVTi mystery continues. FASTTEC used.

[Gerg]

3 hours ago, YarisVVTi2002 said:

Maybe the active surfaces of the Cat have been contaminated by the old engine?

I haven't had good reason to look at many used catalyst cores, but that one does look a bit dark.  Here is one I took a picture of off a 45,000 mile 2007 Mazda 6 a few years back.  The core isn't in focus (that's not what I was taking the photo of), but the core colour is still very apparent and it's quite a bit cleaner looking than your one.  I don't know if your cat. will get cleaner with general use? Hmm.

The oil deposits are awful.  If you were using the car in the same pattern as you were with the old engine, then I think a fully synthetic 5w/30 would be a good investment.

Great that you documented everything in such an orderly fashion - much more to be learnt that way by other owners from your pains.

[Gc01]

I have a quick question when you were turning the key did you get all the normal lights on the dash and did the fuel pump give the sound of it priming. Because i have a similar problem

[YarisVVTi2002]

On 3/2/2020 at 7:17 PM, Gc01 said:

I have a quick question when you were turning the key did you get all the normal lights on the dash and did the fuel pump give the sound of it priming. Because i have a similar problem

Yes I could hear the fuel pump priming, all the lights came up as normal. Have you gone through the FASTTEC process I did? 

[YarisVVTi2002]

On 7/28/2019 at 7:21 PM, Gerg said:

I haven't had good reason to look at many used catalyst cores, but that one does look a bit dark.  Here is one I took a picture of off a 45,000 mile 2007 Mazda 6 a few years back.  The core isn't in focus (that's not what I was taking the photo of), but the core colour is still very apparent and it's quite a bit cleaner looking than your one.  I don't know if your cat. will get cleaner with general use? Hmm.

The oil deposits are awful.  If you were using the car in the same pattern as you were with the old engine, then I think a fully synthetic 5w/30 would be a good investment.

Great that you documented everything in such an orderly fashion - much more to be learnt that way by other owners from your pains.

Thanks. 

I changed the oil to fully synthetic 5w/30 and the engine stays much cleaner. I suspect this will help reduce the sludge and sticky coating build up I had before. 

The Cat error code is still on, even if I clear it, it comes back after 20 miles or so. 

[Gc01]

6 hours ago, YarisVVTi2002 said:

Yes I could hear the fuel pump priming, all the lights came up as normal. Have you gone through the FASTTEC process I did? 

For me when i turn the key to the On position i dont hear the fuel pump priming nor do i get normal lights, the only lights i get are the oil, power steering and abs, after a bit those two turn off. I'm guessing the fuel pump has failed but it happened before and started before. Now it will not start. The cars only done 88k miles

[Gc01]

So i figured it out. it was a tiny fuse that was in a corner that was obscure and difficult to spot

[Ricochet1]

which fuse was it for? which fuse box? good job sorting it.