2017 Mirage cvt high rpm until 60mph/100kph

[Fummins]

I just got told about a higher mileage 2017 Mirage that's reving to 5000rpm before shifting. I'll check it out later today or Monday. First thing I thought was they were driving it around in B or S but nope. They're trying to limp it in. They said once it hits 100kph it shifts and rpm drop to somewhat normal levels. I might just replace both engine and transmission at the same time if the engine shows any signs of clackyness.

UPDATE: fixed…finally.

[Fummins]

I took this thing for a drive, it's super gutless but otherwise, I have no idea wth the other driver was complaining about. It requires far more throttle and rpm to get moving compared to the others and it has a throaty intake sound to it which is kinda weird. The person who drove it in said they didn't notice anything wrong. Stay tuned....

[Fummins]

I took this for a slightly longer drive and had a chance to floor it for a block, rpm went up to 5000rpm and it was slow as hell, only got up to 60kph and it wasn't picking up speed very quickly. It would accelerate faster if you let off the throttle. So far I replaced the maf just for poops cause it only took a min and the air intake temps seemed a bit high with the old sensor.

Time to fire off the parts cannon again. This car has been throwing cat efficiency codes for years now so maybe I'll finally get around to fixing that. It also had a post-catalyst system lean code stored recently. The complete lack of power feels like it could be plugged cat, weak fuel pump or poop injectors. I'll start by blindly throwing the easy parts at it first. I spose I could try to test fuel pressure by deadheading the pump and looking to see if there are any specs for that. But I won't...

The engine runs like a clock, no knock, no ticks, it's one of the smoothest running turds in the pile.

[Fummins]

Well, I blindly fired a fuel pump at this car. No change. Then yesterday I figured I'd try some injectors from a low mileage engine I have on the floor. Of course, car flooded. Had to pull the plugs, blow them out etc... finally get it running again and it had a missfire on cylinder one. Engine light flashing, I pulled injector connectors to find which cylinder it was. So I swapped out that injector with one from a different low mileage engine(I have 3 right now ready to get installed). Car started up. Took for a drive and it felt worse than before. It runs great at idle but when you floor it it has zero power. It reminds me of a 1979 F150 I bought for $40 with a leaky torque convertor seal. That thing was gutless, then I replaced the timing chain(could move the crank quite a ways before the rotor under the dist cap moved). I dont' want to replace a Mirage timing chain, although it'd be pretty cool to see this thing hit a million km on the original powertrain. This thing has over 500k km. I think I forgot to mention that.

Engine sounds off when floored, almost like when you remove the resonator from the aircleaner kinda sound, or flipping the air cleaner lid on an old chevy(it worked on tbi engines too).

The title of this thread should be high mileage-low power.

[BigMW]

How is the compression on those cylinders?

[Fummins]

How is the compression on those cylinders?

Yeah, I should have done that yesterday when I had the plugs out. It's back in the shop, I plan to do a compression test soon. I have put off doing it cause I was hoping it'd be something else. It doesn't seem to burn oil and runs so nice until it's under full load.

[Fummins]

Compression was okay...ish. All above the "service limit", one cylinder higher than the other 2. I checked the codes, air intake temp(cause maf is unplugged), a few communication codes(likely cause I killed the battery when it was flooded the other day), and one code that I've never seen before that could be the problem. Oddly enough the cat efficiency code is nowhere to be found.
Another odd thing is the freeze frame data shows codes being thrown having incorrect odometer readings. I thought they were old codes at first judging by the mileage, but after clearing everything and checking when the ait code was triggered the mileage shows as being over 100k kms ago.

Anywho...I'll figure out what this new-to-me code is and continue with the most embarrassingly a$s-backwards form of troubleshooting that I've done in a while. Weird, I'm sure I scanned this thing a little while ago and only came up with a cat code. Oh well, hopefully, I'll get it fingered out and back on the road today.

[Fummins]

I'm stumped. I'm thinking this thing is just clapped out. It does get pretty clacky when warm too. Not as bad as the car in the video I just posted but it's not as quiet as it is when cold oddly enough....

It feels like it's losing fuel pressure under load. I did replace the pump but the one I installed could be junk. Or have some crap sludge fuel in it...Though it didn't smell rank when I removed it. I don't have a way to check fuel pressure other than deadhead the pump.

Edit: gonna try replacing the cat. Last attempt at getting more life out of this engine. All the bolts heads for the heat shields are rusted so bad that they'll have to be cut and the torches are at my house for some reason.
I pulled the exhaust off and can see inside the back of the cat and it doesn't look broken or plugged at the outlet but it the outside sure looks like it's gotten pretty hot.

[Fummins]

I'll finish this up sometime tomorrow. 2-3 more bolts to go. I'm stunned that every fastener came loose with just hand tools. Even the two nuts(so far) that hold the manifold/cat to the head were rusted to shat but I stuck a 12mm socket onto a little 3/8 breaker bar ,gave it a couple light taps with a hammer and they broke loose and spun right off. Crazy how this thing has 528k kms and no broken exhaust studs, it looks like the manifold had a couple near melt downs. Mitsu should send a few mfg's notes on how to design an exhaust manifold and how to fasten it correctly to an engine so that it doesn't break off after a few years.

Anywhooo, I'm slightly confident that this cat may be effed. The one I'm removing looks like the honeycomb crap might have broke loose and dropped down inside the housing an inch or so. When I look inside the pipe I can see the side of the stuff, when I look at the cat I'm going to install, it looks like it's shoved up higher and you can't see the side of it. I dunno....I'll continue the parts cannon shat show tomorrow though.

[BigMW]

Thanks for doing all these write ups Fummins. My Dinky car is still new, and it hasn't developed any issues yet, but I'm sure down the road I will be re-reading these posts.