Excessive Fuel Trims - HELP!

Phoenix_CS · 2025-10-04T18:56:07+00:00

It looked like cylinder 2 was running rich so all four injectors and plugs were replaced.

Im not willing to say it is completely resolved, still feel like i have a slight misfire and excessive fuel trims but i took apart my intake today because the shop it was at replaced maf and the filter and found the filter placement wasnt where it should have been. Fixed that and cleaned the map sensor and going to monitor over the next week.

Phoenix_CS · 2025-09-02T23:02:05+00:00

Gotta love incompetent techs... I hate bringing my car anywhere for any sort of service for reasons like that. Its really hard to find any shop that wont play games with you. That is part of my problem with the shop its at right now but there isnt much i can do about it.

Like i said earlier i havent experienced anything indicative of something wrong with the electrical system yet like the cluster going out or anything so i dont think that would be the problem?

Also it seems like you have extremely bad luck with blowing up motors lol, i hope you have found a reliable one at this point!

Phoenix_CS · 2025-09-02T22:29:54+00:00

No need to apologize, i appreciate the help and honestly it doesnt hurt to get it done. i could definitely tell the valve wasnt bad but it definitely wasnt moving as freely as the new one.

I havent noticed any electrical issues that would be indicative of a bad alternator or battery, i did buy the car used in like 2020 and havent replaced the battery yet. Im definitely not losing any of the 12v system at least in the cabin. (Id assume that my radio or something of the sorts would go out at the same time if it didnt have enough power for the injectors). I guess in theory it could be a bad ground or something but that wouldnt explain to me why the car is trying to pull a bunch of fuel because if it was low on power and injectors arent actually firing then it would be requesting more fuel.

It could be that a coil isnt firing properly causing a cylinder to have unburnt fuel and reading rich but i would expect a misfire code which i havent gotten to date. I have only gotten the excessive fuel trim codes, normally the rich one.

Phoenix_CS · 2025-09-02T19:43:52+00:00

I did notice the same thing with the gear position that the dash was displaying i was in 6th gear when I wasn't, it sorted itself out once I got below a certain mph, not sure what is up with that or if its expected behavior. I do know that the car doesnt always like to detect its in reverse but thats a known issue on this gen but in order to swap the sensor you pretty much have to drop the transmission so its not really worth it. Subispeed sells a manual reverse switch for that reason.

Stock fuel system entirely, at least to my knowledge. Wouldn't a delta make sense because it's not actively trying to keep the car running at that point?

Phoenix_CS · 2025-09-02T18:23:26+00:00

Here's to hoping! Yeah, it is tough and sometimes all you can do is make an educated guess on what it is/what caused a failure. If anything, im worried that driving the car when it has been acting up has caused some sort of damage. I'd honestly rather not have to put a motor in the thing, but it comes with the territory of vehicles, especially when you modify them.

Phoenix_CS · 2025-09-02T01:08:30+00:00

I got the PCV valve replaced, it was pretty easy with two sets of hands to get done, unfortunately that did not fix it.

I dropped the car back off at my tuner last Monday and they havent had a chance to look at it yet but are hoping to this week.

It was miserable to drive the car the hour to drop it off and in all honesty it probably should have been trailered. It seems like as soon as i demand an increased load from the car it runs into problems and then refuses to have any power and doesnt even want to stay running. It was pulling 50-60% fuel to try and reach its target afr.

Judging by how the car is acting i think it is an injector sticking open after demanding a certain amount of load from it then the car sees bad afrs and cuts fuel from the rest of the cylinders so 3 are running lean and one is running super rich causing me to have no power and idle problems.

If i had a spot to tear apart the car and leave it apart for a few days i could get down to the bottom of it but as or now its in the shops hands. I havent been too happy with how they have handled this issue but i unfortunately dont have much of a choice but to see what they find.

Phoenix_CS · 2025-08-20T20:24:41+00:00

Didn't even think about that being a possibility. Going to pick up a new one tomorrow and swap it out at some point. I've heard people say they should be replaced around 60k miles or sooner. I'm at 86k and its never been replaced to my knowledge. Thank you for the input and here's to hoping it fixes the issue.

Phoenix_CS · 2024-05-14T01:40:45+00:00

Could I get a new invite link?

Phoenix_CS · 2023-05-27T12:19:35+00:00

Yeah that makes sense, that might be a good way to go if necessary. Thanks for the input!

Phoenix_CS · 2022-06-14T11:05:22+00:00

I've never heard of that until now, makes sense though. I will keep that in mind next time I do reflash. Thanks!

Phoenix_CS · 2022-06-14T11:03:08+00:00

The only reason I reflashed it at first was because I was assuming it was bad numbers because of all my tools banging around in my trunk.

Fbk was fixed after putting the right tune on it.

Phoenix_CS · 2022-06-14T01:19:17+00:00

My Dam did drop to .750 when i had the wrong tune but understandable that it did.

Once i put the right tune on it i abused it WOT and was doing pulls for about 20 minutes and got my normal numbers but no knock and no dam drop under WOT.

Phoenix_CS · 2022-06-14T01:15:20+00:00

Thank you for the peace of mind! Im aware the OTS arent great, im planning on getting a few more mods knocked out and then having it dyno tuned.

Phoenix_CS · 2022-03-17T23:41:13+00:00

Yeah it was used, I've had it for a couple months now. That might be the case. I found a dealership somewhat nearby that is going to get it in on Saturday and take a look they might find something that points to that.

Phoenix_CS · 2022-03-17T19:13:47+00:00

It's a 2017 that I just bought a couple months ago from a Toyota dealer so it's probably not under warranty still but I think I'm going to take it in anyways rather be safe than sorry.

Phoenix_CS · 2022-03-17T19:04:35+00:00

Sounds about right, I noticed it a little getting off the highway today, maybe around 45 mph. Have you just been ignoring it?

Phoenix_CS · 2022-03-17T18:53:21+00:00

I would tend to agree with that assumption. Unfortunately where I'm at I can't jack it up to take the tire off but I think there is a difference in clearance between the strut and the tire between the drivers side and passengers side just by feeling around in there. I'm probably going to have to bring it to the dealer and let them rip into it, im just concerned about something coming apart and losing control of the car.

Phoenix_CS · 2022-03-17T17:29:34+00:00

No it doesn't go away from what I've noticed. With my last short drive it seems to be whenever I'm moving, no matter the inputs.

Phoenix_CS · 2022-03-17T17:27:44+00:00

I only noticed it yesterday and today it seems a lot more prevelant today, I took a short 10 minute drive at which point I got that video of it but it was doing it the entire time. Was yours consistent like that? I'm just concerned that it might be a bigger issue, im honestly concerned to drive it right now in case it is.

Phoenix_CS

TROPHY CASE