Please help: Power losses at certain revs.

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Please help: Power losses at certain revs.

Postby Pyr0m4n14c44 » Sat Dec 19, 2015 6:21 pm

Hi there fellow Liberty owners!

I apologise if this has been posted before.
I am completely stumped on what is causing my Gen 3 2000 rx to lose power during acceleration between ~2200 to 3k rpm and is evidentially worse when I use my AC.

I'm not exactly very cluey when it comes to cars (only know the basics). But I've taken a few steps to attempt to rectify this problem with no luck.

I've done the following.

Changed spark plugs (had a spark plug oil leak which I have fixed).
Ignition coil pack.
Timing belt changed (with head gaskets).
Fuel filter.
MAP sensor (2nd hand one).
O2 front sensor
Transmission fluids
Ran injector cleaner through.
Regular servicing.
Reseated the AC belt.

I haven't touched anything in relation to fuel or checked for any vacuum leaks as I am a noob at this stuff :S. If you reckon it could definitely be related to this, I'll give it a go if it's fairly easy and won't be too temperamental on my car.

I also found some refurbished injectors on eBay for 200 for a set if need be.

Also, my Liberty is an auto and I do not have any CEL codes registered nor has my check engine light come on.

Any help is appreciated :)

Cheers,
Andrew
MY01 Subaru Liberty B4 Tuned by Kido Racing


Sequential twins are fun, nothing like letting your guard down then getting a swift kick in the arse at high revs.
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Re: Please help: Power losses at certain revs.

Postby bigBADbenny » Thu Dec 24, 2015 6:05 am

Which plug was oily?
You might want to post/search on subyclub.com as there's lotsa Gen3s there.
What's the exact symptom? Total loss of power or just sluggish?

Interesting thread: http://forums.whirlpool.net.au/archive/1743376
Takeaways: clean maf w/ crc maf cleaner, clean egr vavles, try some 98, reset ECU and if the issue goes away, then comes back, it's likely to be to do with learned values, so check/replace the knock sensor and do the usual knock related precautions eg loose exhaust shields etc.
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Re: Please help: Power losses at certain revs.

Postby Pyr0m4n14c44 » Fri Dec 25, 2015 7:10 pm

Hi Benny,
Thanks for the reply, all the plug seals had all gone at the same time. I discovered this when I was changing the plugs which I got fixed straight away.

It's just sluggish between these revs but the weird thing is, it doesn't happen all the time. It is fairly intermittent and when it does happen I can feel the car pulling once it hits 3k but prior to that (from 2k) it's incredibly sluggish.

I've tried resetting the ECU (I think). I might have done it wrong (disconnected the battery and held the brake in for a minute + left it for 10 mins before reconnection). I don't think the car is in a limp mode of some sort?

I've noticed that 98 actually makes my Liberty worse (especially on cold start ups). It struggles to start even more so than any other fuel. I have to crank it twice for it to turn over.

Please excuse me as I am a noob at car mechanics, but where abouts is the egr valve in question? If it's easy enough, I'll give it a crack to clean it myself.

Also, if the knock sensor was problematic, wouldn't it give a CEL code? Is there any measurements I can try to make sure it's working? Should I just change it to make sure?

I should also look into my exhaust shielding as well too.

Thanks for your response, Merry Christmas to all,
Andrew
MY01 Subaru Liberty B4 Tuned by Kido Racing


Sequential twins are fun, nothing like letting your guard down then getting a swift kick in the arse at high revs.
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Car: 2001 Liberty B4
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