P0300 and P0304 CEL -- uh oh!
 

Cruising in 4th, low rpm, last week my FRS suddenly developed a misfire which quickly turned into a failure to idle entirely and difficulty starting.

P0300 and P0304 came up and I had to have the car towed as it was very immobile.

I will update this thread with my findings.

2013 Scion FRS with 40,xxx kms

Update: Coilpack, plug, all around inspection and no results. Compression is good. No visual warning signs.

Moving onto reflashing. This is a weird one.

All Stock?

HKS Ver2 Supercharger with Ecutek Racerom

ORC clutch and flywheel, perrin light crank pulley also

I think people have had misfire issues with lightened crank pulleys. I could be wrong though. Maybe it'll point you in the right direction.

coil packs dont often fail completly ie short or open circuit , often it apears to be intermittent breakdown or insulation failure at high temps or loads , ecu can go into limp home low power mode sometimes , resetting ecu or clearing dtc codes will usually clear issue tll next failure. Reseting also resets misfire counters, so re occurance of fault can take some time even days or weeks.

The codes were cleared however nothing changed or improved. The car will not idle or drive.

Only P0300 and P0304 are throwing. Tomorrow I am going to stick it on ECUtek because I am concerned about the dealership's competence.

There's a real gross lack of data on the web, or anywhere in general, about these codes or people with similar experience.

Confusus say Your search fu is low my friend :-)

They flat out told me if this was the issue that there would be other DTC's present. What you're saying is that they are blowing smoke up my ass?

As the service bullitens above says "one or more of the dtc present" .

It could be cams it could be coils

hopefully it not the issue below as i believe its the nasty one which bleeds off oil pressure and can lead to bigger problems

http://www.ft86club.com/forums/showp...postcount=2969

http://www.ft86club.com/forums/showp...postcount=2972

one thing they mentioned was that on their tool the timing was reading some completely weird arbitrary numbers that made no sense. Should I be leaning on this bulletin?

Certainly wont hurt.

although they are going to duck and weave a bit if the supercharger is still on car

the ducking and weaving is real. this is painful.

I'm just trying to get them to do an actual diagnosis and not just act so bewildered like I've broken the car with scary aftermarket wizardry.

well I just ruled out ECU or tune issues. I played a bit and the car is definitely suffering the most at idle and only lightly smoothing out as you go up in rpm. It will either idle miss a very pronounced miss and try its best to compensate or it will fall flat and stall.

Op, Do you have a catch can installed???

Yes I do. Cusco AOS type, plumbed into the rear line on the battery side

UPDATE

The tech informed me today that the cam sensor is out of spec and repair parts are on order.

Why do I feel like this may be a thing but not the cause if my misfire? Maybe I have no faith in the FA20 anymore after my experiences.

What say you fellow owners?

Stop questioning dealership's competence... I always assume they are incompetent

FA20 is not an engine to have faith in. You gotta have a back-up plan, especially when you are FI.

Hope you get the issue resolved.

Well I have a backup plan. It's toss this engine in the garbage. However I need to know what's not working before I make any decisions. Over a week and still no results other than report of a cam position sensor being out of spec. They finally got the parts in but now I have had 4 days of radio silence.

I'm supposed to be getting an update today. If this doesn't resolve the issue, there is a huge problem with their troubleshooting. I know how an engine works. Albeit more complex than some.. this is still a small gasoline engine and only so many things can cause this problem.

UPDATE: and this is going to be a disheartening one. No amount of troubleshooting revealed a cause for a misfire so I very adamantly had them perform a check up on the cam position sensors. I got a call pretty quick saying it was oit of spec and a TSB repair would be done.

After the repair was completed and the ecu was reset the car struggled to start and seemed to almost have a hard time learning to idle again. I don't know if this may be somewhat because of my light flywheel and tune. It felt rough still though and initially I could feel a misfire.

After some warming up and a short drive it felt much better. There hasn't been a misfire or DTC since. I am yet to drive the car much but it admirably handled a 20 minute sub-4500rpm test drive.

Why is this disheartening? Well for one if you saw how long it took to re learn idling and how weird the initial low rpm AFR's were you'd be nervous too.

The conditions of the cam sensor apparently going out of spec were also just too weird. The car had been running perfect.. I was cruising along in 4th gear low rpm and instantly the car bogged down, began to fully misfire on 4 and then the condition in a matter of a few minutes deteriorated until it wouldn't even attempt to idle.

I will be doing a lot of cautious testing and some logging this week. I plan to make a new thread with all information presented a little better and in good order.

Any update on this?

Well i got the P0304 dtc too, Kraftwerks supercharge, i was on track when a big loss of power just appeared, and two laps after my cel was flashing.

Any updates ?

Here for the updates as well.

Just happened to me. Coming home from the gym. All of the sudden I heard like a loud clicking sound from the left side of the car (sounded like i ran over a lot of branches). Then the car went into limp mode at which point it died when I got to a stop sign. Got the car towed home. Plugged my reader in and it read P0300

Going to troubleshoot for the next couple of days.

Advice us about the diagnostic !

Same issue here, did work on the car during the winter but the issue came back

Dealer called me a couple of days ago and said that it was the coilpack for cylinder 1 that needed replacing.

I haven't heard back from them yet (been two days) and I have an inkling that they may have run into other problems. I'll update this once I hear back

I had a p351 code several months back and changed out coil 1 myself and the code went away. In addition, I've replaced the spark plugs sometime after the code was resolved. However, a few weeks ago I got a p301 code, so I swapped the newer coil 1 with cyl 3 coil. Its been about 2 weeks and the code has not come back ... yet. When the issue first started I had the stock header on. I have switched back to my UEL uncatted header since I was doing a few other things, including the coil swap.

Is it safe to assume that resolved the issue or could it be this same camsensor issue or even DI seals? The car is NA, full exhaust with ecutek tune. I don't hear popping, but that doesn't always mean there isnt a DI issue. RPMs do drop a bit when in stopped in neutral, revved to 2-2.5k. Almost like its about to stall out at times. I know, more data is needed. I really need to datalog but just havent gotten around to it.

I went to see my tuner for datalogs and all was ok... AFR was good, the variable was good, timing was good. I removed my direct injector, all was fine. I'm afraid if it could be ecu itself...

I suspect a cam sensor now maybe so I'll try to take the resistance on each sensor..