FR-S Issues

[patelk100]

This is gonna be a long one, as I don't want to leave behind any context.

2014 FR-S Monogram M/T

To preface, I am running the OFT Stage2+ E85 tune with Tomei catless headers, Tomei Overpipe, MXP catless front pipe, and an Invidia catback. The exhaust does vibrate a fair bit and I'd assume it is possible that it could vibrate and back out bolts. I do have some transmission upgrades but they are irrelevant to this issue. I got new spark plugs installed 1k miles ago along with BRZ coil packs that were in like-new condition off a very low mile car. I also had an oil change and Verus clutch fork/pivot installed at that same time.

Timeline from beginning to end

Saturday, April 30: I just switched back to E and after running it down to gas-light on 93 Premium. I prefer McClure Oil for my Ethanol gas station since they say they have a minimum of 70% ethanol and 103 octane but it was closed that day so I went to Speedway which like most gas stations, only guarantee 51%-83% ethanol. But 51% was the minimum, and I’d assume that it would be closer to actual E85. In retrospect, I wouldn’t do that again, but at the time I did it. I know the margin with the OFT E85 tune is safely about ±10% of actual E85 and just said fuck it since I was impatient and took my chances. I switched to ethanol because it was now brisk spring and my past experiences with cold starting E85 in the winter were not fun with an OTS tune. I drove it a few miles before I flashed over to clear the fuel lines.

Saturday, May 7: I filled my tank the rest of the way with McClure’s ethanol which I explained above. Ran well as far as I could tell. The real problems started to happen when I was at about 6/10 done with the tank after McClure which is when I noticed my car started having issues.

As of recent, my exhaust has started making slight popping sounds almost like a tiny little burble but very small and barely noticeable, and it's usually at random when the engine is under any load. I know it vibrates a lot and so I chalked it up to maybe my exhaust getting slightly loose and I just needed to tighten it soon.

Tuesday, May 10: In the morning my CEL comes on along with the traction light. I continued driving since I was going to school and was like a mile away and went in for the day. The pops were maybe worse and the car may have felt slightly off, but I don't remember thinking that at the time since I had a lot of other stuff on my mind too.

*This may have nothing to do with it, but the weather just recently warmed up a decent amount too. It's been mid-to-high 60s the past while, and when this happened, it was 75 in the morning and was going to be 86 in the afternoon. This is a very large spike as last week the max temps were in the mid-60s and that day was the first day it was gonna be super hot. I say this as it could affect hoses, gaskets, seals, and such with the dramatic weather changes.*

I get out of school and start my car, it sounds like a mix of rod knock and like someone put a very raspy cam in my car. After letting it run for a few seconds, I turn it off. I tell my friend to record and then again I start the car and also give it some tiny revs. That video is below.

Video: https://www.youtube.com/shorts/xZfEwa9Eqd0

I gave it tiny revs during the cold start period after and noticed the pops were much worse. Once the cold start was over, it sounded fine apart from a slightly different exhaust tone.

I drove it home and scanned codes: P0171

The second part of the video is me looking at the live feed from the OFT and having no idea what I am looking at. I was just looking to see if I could see something weird like knock correction or anything. I know the car somewhat can correct for shitty gas from the open and closed-loop for fuel readings.

I thought it was one of the BRZ coil packs since they sat out of a car in the open for a while and it could cause a misfire which is what I thought the issue was.

I cleared the CEL and went around the block to see if it would help but the issue was still there but with no light. I had an appointment with Toyota for a sticky clutch (solved, it was a loose clutch master cylinder from what I assume was from my verus clutch fork install) soon so I just left it and figured I'd let them know when I drop it off.

I went to Toyota today and I tell them what I know at 3:20. At 6:42 my car is done! I am told by the service advisor that the issue I was having was because of my ECM "not being plugged in all the way". I look at the sheet and the code they pulled from the CEL is "lean bank 1". I figure, whatever, because the tech did take it on a test drive and I mean, if he drove it and says it's fine then it has to be fine right?

I start driving and notice the sound is sounding even worse. It's shaking at idle, the exhaust sounds and feels loose, and still runs like absolute horse cock and the CEL comes back 2 miles down the road. I turn around and drop it off to the service advisor before he leaves since they close at 7.

He says he’ll check it out tomorrow and promised to be more thorough.

After writing/rethinking about the events that led up to this and also given I have done more research since the initial issue, my personal opinion of the issue is that I have shitty ethanol OR my PCV hose is leaking which would be bad. I say PCV because maybe a combination of weather, vibrations, and bad luck could maybe cause a vacuum leak.

I’ve invested in an E85 tester from amazon that gets here Saturday and I might consider getting ethanol additive to maybe see if that could help remedy the issue.

This engine was just replaced and it has 5k miles on the block and about 1.5k of those were on E85 in Winter (terrible idea with shitty OTS, I've learned). New OEM block from and installed by Toyota and my old heads were rebuilt. 78k miles on chassis.

Forgive me for the novel I just wrote above with scatterbrain. I've given all the context to any variable I can think of that could cause this. I've never turned a wrench in my life so that's why I'm asking for help.

[patelk100]

I also just bought E85 additive just now after my friend who has a car on E told me to try it. He asked if the car shaked on idle which it did and then he said to try Ethanol additive because he's seen pretty good firsthand results with adding seafoam and additives to fuel. I went with Star Tron Enzyme Fuel Treatment Concentrate on amazon and that gets here Monday and my E tester gets here Saturday.

[Tcoat]

I know this is as basic as it gets but sometimes basic gets missed even by techs. Have you checked your air filter? A plugged filter is often the source of a lean code.
If not that then my second guess is a vacuum leak as you mentioned. That can be much harder to chase down.

[patelk100]

I have an update from the dealer. At 10 am today they texted me and said their recommended immediate service is to spend over $2k and replace my direct fuel injectors. I obviously said no to authorizing that repair and still plan and try to fix it myself before trying other options. I have had bad repairs and dodgy work done by this Toyota dealer in the past but I can see how they came to this conclusion and I don't blame them.

Rather than throwing new parts at it until it's fixed, I plan on continuing with my plan to add a fuel stabilizer and test locally for the highest ethanol rating pump I can find. I then plan on adding more ethanol along with the stabilizer in order to maybe improve fuel. I also found in my research that any misfire would read in the check engine light codes, so I was wrong. My car isn't misfiring at all so that means the spark would be fine. After this, I will look for vacuum leaks and maybe drop the tank and put in 93... or just take it to a real mechanic at that point. I will also be checking the intake and making sure the MAF is all the way in like you said when I pick up my car.

That is another issue, how sustainable is it for me to drive like this? I'm on ethanol and its running worse than at the beginning. This dealer is also about 10 miles from my house so I am somewhat concerned about driving it home.

[patelk100]

Another update: I got my car back and filled it up with E85 the rest of the way. It was half full but ran fine and I could hear the car running rich and popping in the exhaust to make up for the lean bank 1. I added 2 fl oz of Stabil 360 ethanol treatment as per instructions. No change so far. Still need to read the code again and I may clear it again but not sure. However I looked at my stock intake and the bottom is completely cracked and falling apart and there's 100% a leak in it. Considering getting a grimmspeed or another oem intake as I don't want to dump money into it anymore.

[CSG Mike]

Try getting those injectors cleaned.

[patelk100]

Originally Posted by Tcoat

I know this is as basic as it gets but sometimes basic gets missed even by techs. Have you checked your air filter? A plugged filter is often the source of a lean code.
If not that then my second guess is a vacuum leak as you mentioned. That can be much harder to chase down.

My intake is almost completely broken, I pieced it back together to the best of my ability and now am looking at Grimmspeed intakes to replace my broken OEM one. Irony of this situation is the same dealer is the one who broke my intake originally while putting in a new block that they proceeded to time wrong and also have break down on me on the way home.

I asked my friend about his Grimmspeed and apparently he had the same issues as me. He had a broken intake and was getting the same P0171 lean bank 1 code and with similar symptoms but he also had a misfire from bad plugs.

I also cleared my CEL after remedying the broken OEM one to my best effort. I drove around for 25 minutes and the light didn't return! I still noticed some pops on downshifts but I think its a combo of an exhaust leak and the intake leaking to this issue. Gonna have Meineke check/fix? my exhaust and make sure its all sealed and I'm going to be ordering an intake tomorrow.

Only thing I am iffy about is my friend said that the car has to learn the new intake and I might get CEL from running the intake. He said I can just turn off the CEL and have my car run fine but I don't want to disable my CEL and that's the only thing holding me back from getting a Grimmspeed. I love their product and engineering and development, but a CEL from it could be a dealbreaker for me over a TRD intake.

Thank you for recommending me this though, I probably would not have ended up checking if not for this comment.

[Tcoat]

Originally Posted by patelk100

My intake is almost completely broken, I pieced it back together to the best of my ability and now am looking at Grimmspeed intakes to replace my broken OEM one. Irony of this situation is the same dealer is the one who broke my intake originally while putting in a new block that they proceeded to time wrong and also have break down on me on the way home.

I asked my friend about his Grimmspeed and apparently he had the same issues as me. He had a broken intake and was getting the same P0171 lean bank 1 code and with similar symptoms but he also had a misfire from bad plugs.

I also cleared my CEL after remedying the broken OEM one to my best effort. I drove around for 25 minutes and the light didn't return! I still noticed some pops on downshifts but I think its a combo of an exhaust leak and the intake leaking to this issue. Gonna have Meineke check/fix? my exhaust and make sure its all sealed and I'm going to be ordering an intake tomorrow.

Only thing I am iffy about is my friend said that the car has to learn the new intake and I might get CEL from running the intake. He said I can just turn off the CEL and have my car run fine but I don't want to disable my CEL and that's the only thing holding me back from getting a Grimmspeed. I love their product and engineering and development, but a CEL from it could be a dealbreaker for me over a TRD intake.

Thank you for recommending me this though, I probably would not have ended up checking if not for this comment.

That would do it.
You don’t disable the cel by clearing the code. Just clear it and see if it comes back after sealing up as well as you can.

[patelk100]

Originally Posted by Tcoat

That would do it.
You don’t disable the cel by clearing the code. Just clear it and see if it comes back after sealing up as well as you can.

That's what I did and I drove around for 25 minutes and it didn't come back. I'm gonna drive it a little more this weekend before I buy a new intake but I think there's a good chance it's the source of my problems.

I was talking about disabling the CEL in the case that when I get the grimmspeed, it can cause a CEL from just the intake pulling in more air from what my friend told me. He said he got a check engine light from it but he just disabled it, but that's what I don't want to do, as I like my CEL working.

[patelk100]

Well, more research and testing later, Toyota was right. My DI are bad and I need to either rebuild or replace them. Considering replacing is $2200 and rebuilding is about ~$300 in parts, I will try to rebuild them. I might explore other options though of just getting rid of the car at this point or seeing if a independent shop would be willing to do it.

[blsfrs]

Originally Posted by patelk100

Well, more research and testing later, Toyota was right. My DI are bad and I need to either rebuild or replace them. Considering replacing is $2200 and rebuilding is about ~$300 in parts, I will try to rebuild them. I might explore other options though of just getting rid of the car at this point or seeing if a independent shop would be willing to do it.

Check around. You might find a used set of DI on Ebay. Maybe post in the WTB of this forum. Other than professional cleaning and testing, I don't think they are "rebuildable".

[FrickingReallySlow]

Michele Abbate has a massive part out and tons of OEM parts like DI for sale.

https://www.ft86club.com/forums/showthread.php?t=138524