I NEED Boost... Opinions puh-lease

[Focus_Sh1ft]

I'm definitely a little worried about that, but everything else seems to be running fine. I'd expect to see more adverse side effects if the ECU was crapping out (esp. from what we've seen with yaris2010RS). It's almost like the only problem is fuel delivery is being adjusted too slowly. For example, when I hit the gas during idle the mixture goes lean for a few seconds, then overly rich. If I go light on the throttle it will sometimes recover and then go back to being lean before kind of settling around stoich.

Any ideas on how to test fuel pressure? The pump is probably okay if it's actually delivering too much fuel, but maybe the regulator is getting stuck...?

[Bluevitz-rs]

Yeah you just need to get a pressure gauge to go under the hood where the fuel line connects up to the rail. There's a quick release fitting there. I think you need a special tool to get it apart. That is another good possibility. Maybe dirt got through the in tank filter and is making the pressure reg slow.

[Focus_Sh1ft]

Ok, cracked open the ECM. Two things worth talking about.

First, pretty sure I pushed a cap off one of the pads lol. Oops. Easy enough to fix though.



This was a lot more noticeable... I don't think i knocked this out of place. Regardless, WHAT IS THIS. I've done quite a bit of work on electronics but never seen something like this before. (Bottom right corner, next to white square)



Otherwise, things look good...

[yaris2010RS]

oooooo.... that doesnt look good, im sure CTScott will be able to tell you what that is.

glad to see you got into your ECM and it sounds alot like the same issues i was having. If you learned anything from my thread, dont drive it too much.

Also just a side note, check your blowby from the breather tube. 2 years boosted with no serious problems? congrats man and knock on wood. I like to think i would have made it 2 years if i didnt have my ECM issues.


also when was the last time you did a tune up? fuel system cleaner and spark plugs? when my car was acting up i did a tune up and it got better so that was definatly a contributing factor

[Focus_Sh1ft]

Spark plugs are (were) only a little over a year old. I actually just bought seafoam for the first time.

Not driving at all until this is solved. Just watching the car idle makes me cringe and I don't want to leave it running long during troubleshooting lol...

Definitely going to shoot CTScott a PM. How did that part look on your ECM (if you remember)? It sits between two traces but doesn't look like it should bridge them

[yaris2010RS]

ill look through the pics in my phone and see if i caught that in one..... If i wasnt out of propane for my garage heater and it wasnt so damn cold in my garage id go and open up my new ECM lol.

[Focus_Sh1ft]

Yeah, that whole winter thing. Hate it.

I'm praying this is related. The only thing I HAVEN'T checked is fuel pressure, which is going to be a pain. From what I can see it's going to have to be done out of the sender assembly because I don't have fittings for hookup in the engine bay...

[yaris2010RS]

TaDa!

[yaris2010RS]

use the white square label as a reference

[Focus_Sh1ft]

Holy SHIT. That might just be the problem......

And by might be the problem, I mean DEFINITELY is the problem.

You sir. THANK YOU.

[yaris2010RS]

what happened to yours? lol, it doesnt look burnt.....

[yaris2010RS]

y did we move back to your thread? my thread is only 7 pages, yours in 25......

[Focus_Sh1ft]

I wish I knew. Hopefully it didn't happen while trying to open the ECM. There isn't really any marks around it though (the cap had a bunch).

Tomorrow I'll resolder the cap and throw the ECM back in the car and make sure I get the same result.

Either way, looks like the ECM needs replacement lol. But hey, if I've finally found the problem I'm incredibly relieved.

[yaris2010RS]

i would imagine its just some type of diode, im sure you could fix this yourself (maybe wait for CTScotts input on this)

[Focus_Sh1ft]

That would be great. My only concern would be figuring out the correct specs.

Tomorrow should be an interesting day. Hopefully one that see me driving the Yaris again and not borrowing my mom's Sienna lol -.-

[yaris2010RS]

you had to resolder the cap back on? dude that sucks.......

did you find any loose pieces from it in the ECM case?

PM me if you need the numbers off that component, id open up my ECM for ya. (and im waiting for a reason to open mine up and cover it with di-electric grease and properly reseal it

[CTScott]

The obliterated device is a large diode. The markings on it are "T3 81". If you would like I can pull the one off of the ECM in the picture below and send it to you. I have been using this ECM as a sacrificial lamb for people needing components.

ECM 1.jpg

[Focus_Sh1ft]

Great news! Threw the ECM back in the car and we still have the same problems! (I must live a pretty depressing life if I consider that 'good news' )

The obliterated device is a large diode. The markings on it are "T3 81". If you would like I can pull the one off of the ECM in the picture below and send it to you. I have been using this ECM as a sacrificial lamb for people needing components.

CTScott - is there ever a time you don't pull through? lol
Are the markings significant to you? I ask for two reasons. One: could I possibly pick up an equivalent diode at a local electronics store? Two: I noticed yaris2010RS has what looks like 'T3 91'. Wondering if there's any substantial differences. For reference, my ECM is for a 2008 automatic (part# 89661-52G50).

If all else fails, I'll gladly take you up on your generous offer. Thanks again!