GR86 Power Loss/Reluctance to rev

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Totally Hooked
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Just had a weird experience which has got me a bit pensive, and wanted to get some opinion on it or see if anyone has experienced the same. Probably a long read.

This morning, drove up to my parents....~100 miles or so, all motorway. No issues (or not that I noticed), but it was mainly a gentle cruise anyway.

The car then sat for most of the day until I decided to pop out for an afternoon drive about 4pm. For the first part of the drive I didn't notice any issue, but I wasn't really pushing hard, just keeping up with traffic on main roads while the car warmed up. I turned off to find some quieter roads and still didn't notice anything whilst I was driving quickly, but not pushing all that hard.

First time I noticed an issue was when coming out of a village into an NSL section. It was a long straight with no one in front so I decided to just open it up hard. But as I pushed the throttle down there seemed to come a point where the car just stopped responding....at anything over about halfway down the pedal travel, I could do what I wanted and nothing was happening...the revs would climb, but slowly, as though I wasn't giving it enough gas, or was a gear too high. Even on a long straight, it felt like I could have my foot flat to the floor and I'd never get anywhere near the limiter. Foot hard down and I couldn't seem to get it past about 6k, and that took a while....not like this car at all.

Even when I dropped a gear, the car seemed reluctant to rev out. But if I slowed down a bit (so keeping it around 4k revs or so and using less of the pedal), it still felt torquey and responsive. I then tried dipping the clutch and stamping on the throttle....same thing. The car felt very reluctant to rev, like anything past 50% throttle just wasn't registering, even out of gear. Hmm.

Not far from the Lotus factory, I pulled over and shut the engine off and quickly did the pedal calibration thing...although it didn't feel like the problem this usually solves (laggy pedal), but I thought worth a try. Restarted and carried on, but it was the same; car felt fine up to a certain point around 4-5k but nothing over that.

Got a bit worried and decided to cut my drive short by heading back toward the dual carriageway...I figured hard acceleration along a sliproad would be a good test. To get there I had to head through a town and came up to a level crossing with the gates down. Had a bit of a wait, so I shut the engine down and chewed my lip, worrying.

As the train passed, I switched the ignition on and did the pedal thing once more (why not). Restarted and drove on. Car felt fine but I was in town so wouldn't notice a difference.

Came up to the DC and on the sliproad, gave it a bootful...and it was fine. Pulled strongly all the way to the redline, like normal. When I had my foot on the throttle past about 50%, where it had been feeling dead before, it now felt responsive again and I could feel the car responding to quick inputs while deeper in the pedal. Dropped a gear and did some hard pulls...no problem. Then I dipped the clutch and revved it out....hit the limiter with no problem.

I turned off the DC a little way up to find some twisty roads again and the car felt absolutely fine. Pulled as hard as expected, and was able to get it up to the limiter in lower gears with no issue.

I'm not quite sure what happened. It felt almost as though the car had gone into limp mode, but where most limp modes limit you to 4k revs or so, this didn't. It just felt like the throttle went dead after a certain point. And there was no sign of anything untoward....no warning lights, oil/coolant temps fine, engine sounded fine, no unusual smells or anything. It wasn't unduly warm outside (22c or so). Car has not been abused, only on 3.2k road miles with an oil change at about 1.5k so it's run in and looked after.

Something to worry about do we think, or just a one off problem or gremlin with the throttle mapping? I will see how it responds on the drive home, but I'm a little worried about it being something more sinister despite the engine being seemingly healthy.
 
Just got home. No issues at all all the way. I gave it the berries, as they say, joining the A11 and it responded fine. Same when I got near home, pulled out of a junction with some exuberance and didn't feel any hesitation. Wondering if unplugging the pedal last week to experiment with the Pedal Commander might have mucked up the calibration, and it took a couple of the resets to sort it....can't remember if this is the first time I've properly driven the car quite hard since doing it.
 
Hopefully all sorted then - I haven't had anything like this myself so far, so here's hoping it's a now-resolved one-off and full berries availability is maintained.
 
Subaru engines are typically very grumpy and fussy no matter how new they are, so it could have just been the pedal commander, or….it could be something the engine didn’t like for a split second under load. To be safe, I’d check the fluid levels, have a look and a good listen to it at idle. On a warm day, on 95 RON with slightly less oil than is ideal, it could just give the engine a little scare.
It’s probably nothing, so don’t let it bug you unless it recurs, then just chuck it into a main dealer and the warranty will do the rest 👍
If a Subaru engine is making you paranoid about it blowing up, then it’s working just fine.
 
Subaru engines are typically very grumpy and fussy no matter how new they are, so it could have just been the pedal commander, or….it could be something the engine didn’t like for a split second under load. To be safe, I’d check the fluid levels, have a look and a good listen to it at idle. On a warm day, on 95 RON with slightly less oil than is ideal, it could just give the engine a little scare.
It’s probably nothing, so don’t let it bug you unless it recurs, then just chuck it into a main dealer and the warranty will do the rest 👍
If a Subaru engine is making you paranoid about it blowing up, then it’s working just fine.
Yeah I will keep an eye on it. I checked the oil last week and it was perfect. I only ever use premium fuel (Tesco Momentum usually) but I did fill up last night and wondered if maybe I'd got a bad batch.
 
Noticed you’re in Kent, if you’ve not had your oil pick up tubes cleared yet (mine had RTV clogged in them at about 1,800 miles), Slowboy Racing near Brands Hatch is owned by a chap called Neil. The man is basically a Subaru Buddha, what he doesn’t know isn’t worth knowing. Cost me £240 to clear the RTV build up, only two hours to do 👍
replaced the oil with Millers 0w-20 (I don’t get mine that hot) as well and the car is definitely happier.
 
Yeah I've had this once.

Not a lot to say, was on motorway doing a 4 hr trip sat at 70mph, went to accelerate and had the same thing you did. Wouldn't rev, or it would but very slowly past what I remember being about 4000rpm.

Switched it off and on in a service station down the road and its not come back since.
 
I had this once on my M135i, thought it was serious but after turning the car on and off it disappeared and never came back.

Put it down to a sensor overread or something but never actually found out the cause.
 
Maybe it was just an anomaly then, and not a result of using the pedal commander. It's certainly felt fine since.
Noticed you’re in Kent, if you’ve not had your oil pick up tubes cleared yet (mine had RTV clogged in them at about 1,800 miles), Slowboy Racing near Brands Hatch is owned by a chap called Neil. The man is basically a Subaru Buddha, what he doesn’t know isn’t worth knowing. Cost me £240 to clear the RTV build up, only two hours to do 👍
replaced the oil with Millers 0w-20 (I don’t get mine that hot) as well and the car is definitely happier.
Yeah I saw your post a few weeks back. Something I might consider although the RTV problem doesn't bother me hugely at the moment.
 
This happened once to me once when I had run the fuel tank past 0 miles range.

Once I filled up it was fine.
Ooo. I think the tank was pretty dry the night before when I filled up. Maybe it was something like that then.
 
So this happened again just now, for the first time since the first occurrence. However, I did have an almost empty tank - in fact, I was specifically on my way to fill up, and the pump clicked at 43-44 litres, so it was pretty empty. Restarting after fill up, felt fine. Wonder if a low fuel level can trigger the dulled response. Again, engine feels and sounds fine otherwise, all fluids fine too.
 
GPF don't really need any active regen (which would just be seen as a high idle during the process/the engine not turning off when you thought it should) - the exhaust gets hot enough as it is to burn off any soot.
 
Had the same case, BRZ but car is technically the same, isn't it?


Looks like whatever triggered it, it's called "limp mode" but can't say more details. I had no time to took it to the dealer for inspection.
 
Yeah I've had this once.

Not a lot to say, was on motorway doing a 4 hr trip sat at 70mph, went to accelerate and had the same thing you did. Wouldn't rev, or it would but very slowly past what I remember being about 4000rpm.

Switched it off and on in a service station down the road and its not come back since.


Come to report that it's done it again. 30 minute 70mph drive down dual carriage way left the car unwilling to rev, not as bad as it was the last time where it almost wouldn't rev above 4k but still restricted where it felt like a 1 litre Corsa. No odd sounds or anything.

Switched on and off and it went away.

Went for a blat tonight for 30 mins and was fine, in fact it felt like it was pulling harder than I've ever felt before tonight.
 
I’ve just had this happen to me. Was fine yesterday and for the first part of the journey.

Got on to the motorway and gave it some beans and it just didn’t do anything at all. It accelerated but more like a fiesta than anything.

Did also try turning it off and on again at a set of lights but didn’t fix it. It’s just been serviced so checked oil level and all the obvious stuff but all looks okay to me.

Leaving the car now and will be coming back to it in a few hours so hope it’s okay again then. Fuel level is fine, have about half a tank in.

Very strange feeling.
 
Left it a few hours, drove it 30 miles home and all is fine now. If it happens again I’ll be getting it into the dealer for checks.
 
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