Stay tuned

[YarisPR]

Originally Posted by cali yaris

YES

Those would solve jason's problem, but would they work on my case?



And now that Fuel Pumps are mentioned, I got my fuel pump and hose replace because they were "deformed", the dealership took care of it, can it be that the fuel pump is damage again?

[Jason@SportsCar]

Originally Posted by YarisPR

I just saw the video u posted on YT.
-When the misfire appears, does your throttle respond only if u press it lightly?
-Goes away a few seconds later?
-Does you Check engine light blink?

Sorry for asking too much but I'm having a random misfire and the car does the same buzzing sound (not too nice to hear ) when it occurs. And it happens after a long drive (1.5-2 hours) averaging 80-90mph specially when shifting from 3rd to 4th gear

Throttle position seems to be irrelevant, the engine is flat no matter the input.

It does not go away a few seconds later, takes more like a 30-60 secs depending on the severity.

CEL was flashing, but no code was stored during the Saturday occurrence. On Sunday the issue was bad enough to keep the CEL on and we pulled P0300, P0301, P0302 and P0304 - all misfire codes.

In our case this happened in Turn 6 at Thunderhill each time. Previous to T6 you are dropping down a big hill (the video does not do the elevation justice) in to a medium speed (3rd gear) right hander, then just a slight lift for the left (T6) and this is where the starvation would occur.

We think that all of the fuel is loaded to the drivers side rear of the tank previous to T6, then the lift and sudden left turn pulls all the fuel to the passengers side front of the tank, and this is enough to get the pump to suck some air even at half a tank.

[YarisPR]

Originally Posted by Jason@SportsCar

We think the issue is the tank/pickup, as we only had this problem in Turn 6.

Certainly a new fuel pump, one with a better pickup design could help, if that is in fact the issue.

But putting more demand on the fuel system with some of those other parts could make the issue worse.

Piggy back is in the works. We can not touch the throttle body. And we are looking at fuel cell options.

Jason, can u confirm if what I wrote earlier happens to you? cause the syptoms are the same and u probably find the answer sooner than me

[Bluevitz-rs]

We had the exact same problem with a '89 Honda CRX at Mosport International Raceway in turn 5B. Only it didn't set the check engine light. It would just misfire for a second or two. And it only occurred if we had less than 1/2 tank of gas. We later had problems with oil pressure in the same corner but that set a code and VTEC shut off.

Edit:
It is possible that the ECU is going into fail safe to try and save your non existent cat because of the misfire. The CEL is flashing to warn you of imminent damage to the cat due to the misfire. I've had this happen with my Echo on the track, but I don't have TBW, so it possible the ECU is cutting back the throttle.

[Jason@SportsCar]

Originally Posted by YarisPR

Jason, can u confirm if what I wrote earlier happens to you? cause the syptoms are the same and u probably find the answer sooner than me

I don't think we are experiencing the "same" problem. On Saturday this happened well into the race, with two laps to go, and less than a 1/4 tank of fuel. On Sunday I got on lap 3 with half a tank, and then again near the end of the race when the low fuel light was on - but always in the same turn.

[Jason@SportsCar]

Originally Posted by Bluevitz-rs

We had the exact same problem with a '89 Honda CRX at Mosport International Raceway in turn 5B. Only it didn't set the check engine light. It would just misfire for a second or two. And it only occurred if we had less than 1/2 tank of gas. We later had problems with oil pressure in the same corner but that set a code and VTEC shut off.

Edit:
It is possible that the ECU is going into fail safe to try and save your non existent cat because of the misfire. The CEL is flashing to warn you of imminent damage to the cat due to the misfire. I've had this happen with my Echo on the track, but I don't have TBW, so it possible the ECU is cutting back the throttle.

The easy fix for us may be to start with more fuel. But the right thing to do would be a fuel cell.

[Bluevitz-rs]

Yeah, fuel cell FTW... literally HAHA

[cali yaris]

if you do a pump, will you do a return line?

[Jason@SportsCar]

Originally Posted by cali yaris

if you do a pump, will you do a return line?

I don't think we can, we have to use the stock fuel injection - less the injectors - so I don't think we can alter the fuel rail.

All part of the challenge of find a cell that will work with our car. New racecar development is fun.

[largeorangefont]

Are you allowed to do a small surge tank?

[Jason@SportsCar]

Originally Posted by largeorangefont

Are you allowed to do a small surge tank?

Yes.

[Jason@SportsCar]

Sunday qual and race, with under car shots.

http://www.youtube.com/watch?v=yGekLZMYms8

[Jason@SportsCar]

Fingers crossed, should be getting the new engine management today... Going to make for a busy weekend. Tuesday the car goes in for the new graphics.

If anyone finds themselves at the Lakers VS Clippers game on the 14th, the Yaris will be there on display in the Toyota both.

Between the graphics and ecu work there will be little time left to work on the suspension, but it should be here before our Apr 24-25 double national at Buttonwillow.

Now where are my wheels?????

[Jason@SportsCar]

My Editor has created an "unofficial" SportsCar magazine website to catalog our past projects. It currently covers a couple of our past project cars as well as some other fun projects.

In the future we will be adding more images, as well as more current cars (like the Yaris, after it prints in the magazine).

http://sportscarmag.wordpress.com/

[mojoyaris]

My car would cut out just like yours did. Alot of the other posters in the forum would give all kinds of advice but really don't think they were running their car 10/10ths.

You run your car pretty hard and the fuel starvation seems to be a natural part of the Yaris due to it's nature to run ....lean.

Hope you find out the fix for it while staying within the boundaries of your class. Good luck!

[Jason@SportsCar]

The Yaris is being wrapped right now, will be ready in the AM. Cant wait to see it.

[cali yaris]

well? let's see some visual goodness!

[Jason@SportsCar]

Originally Posted by cali yaris

well?

I am sitting at my office now waiting for the one person who can approve the check I need pay for the wrap. The guy that did it says it looks sweet.