How are you driving the car....what RPM do you shift at?
When you get on the freeway/highway, do you wind it up to 6k rpm in 2nd gear?....with the "Pedal to the Metal" (wire)

 

get Wallace to give him his walkies and some treats! :biggrin:

wish i could help, but mine's older. i think some here have reported having an issue with the electronic throttle body control but there's lots of things that could cause your symptoms.

no stored trouble codes or check engine light, i assume.

 

Hahaha - Maybe I should hang some cheese on a stick from the hood!!! Good one! Thanks for your time.

 

Hi, Trailangel and thanks for your reply. I drive the same way under each circumstance, both when Gromit is running very well and when he's dragging a bit. I seldom rev over 4000 or more and regardless, and I know it's hard to understand, it's just the feel of the car - full power vs. "lean" feel while running, not only when accelarating. I guess an analogy might be: running on full gas vs. running on watered down gas. Thanks for your time!

 

Try driving the hell out of it for a day. The boxer engine likes to stretch its legs, and if it is constantly babied, it might bog down on you.

Shifting a little later and letting it make some noise might make for a happier car.

 

I'll give it a go! Thanks for the suggestion!!!

 

I agree... definitely give it some stick and see what happens. Subies respond very well to the occasional "Italian tune-up"!

 

I agree as well with the previous sentiment. I noticed my Impreza 2.5N/A was dragging for a while, and I started really giving it the beans. Everything started working better. Now, driving with the A/C on killed any 'feeling' of performance, so I rarely used the A/C. Side effect of that was a miserable commute home while the car bucked and stuttered when the temps went over 80°.

Granted it was a 2003 n/a, but was almost always a blast to drive. I couldn't get over the rodeo ride in hot weather...hence 2007 FXT. :smile:

 

Well, in a 2004X N/A rest assured that when you get close to WOT the engine computer assumes you really want to GO and automatically turns off the A/C compressor for you! :icon_frown: (It does start soon working again). I have been experimenting a bit and it seems to be more related to throttle position than actual RPMs.

Haven't read my manual in awhile but MT shift points are usually "minimal" recommendation rather than "average" or "normal" imho. The "power band" of the engine is somewhere between 4000 and 5000 rpm IIRC, so for maximum takeoff you shift at those points and not worry what the corresponding speed is. I really like the feel of doing this, which is another reason for me NOT to get an XT ... I would probably get lots of speeding tickets! :biggrin: And anyways the N/A already has more HP than lots of Turbo 4cyls had when I was first driving.

 

Our 10 premium feels sluggish(compared to our 12 second fxt) but being we have the auto in both they are going to.

As others have suggested, dont be afraid to open her up.

 

Our 2.5X 5mt felt sluggish tonight, but I also noticed a lot of spark knock. I've been driving the WRX too much lately to really compare. I'm used to 1/4 throttle bringing the car up to 55mph effortlessly, darn turbos.

I'm wondering if there's some truth to the "Italian tune-up" to blow some carbon out of the engine.

 

i had a simular issue in my bmw. in colder temps accelerating was fine, hotter days engine revd but seemed to be sluggish. well turned out to be the pressure plate springs. oem clutch that had 120k miles and had to start in 2nd (i kinda destroyed 1st drag racing and donuts). new clutch, stage 1 with 80lb(?) pressure plate did the trick.

 

Thanks to everyone with your input and ideas. I will be getting out this weekend and will try the Italian Tune Up! Kind regards to all.

 

Check all ground wires under the hood and underneath the car, make sure they are nice and tight. Most take a 10mm socket, except the two large ones connected to the front of the intake manifold, I think they are 12mm.

Also, with the car parked and the engine off, pump the brake pedal until it becomes stiff and hard to push. When the engine is re-started it will reset the vacuum balance for the brake booster. Mine occassionally gets a little draggy and this brake vacuum reset routine seems to cure it. I do not have an explanation for it, but its free and easy to try.

Turn off the VDC when the draggyness is going on and see if it helps (button on lower left of dash).

Are you using the parking brake a lot? Have dealer check and make sure its adjusted properly.

Also might try disconnecting the negative (black) terminal from the battery overnight and reconnecting in morning to clear all the ECU's learning. When you drive for the first 50 miles after this, drive it like you stole it. Keep in mind that the first 20 miles or so after a battery disconnect it will feel kind of thrashy and lurchy (shifting and clutch response) or at least mine does during about the first 20 miles.

Make sure oil fill cap is on tight.

Check that the spark plug wire boots are securely pressed onto the ignition coil.

As far as dealer figuring out the problem -- won't happen. If the Check Engine light is not lit (no DTC codes stored), they're lost.

 

Lone Ranger, thanks for the suggestions. I'll be trying them all - learned a lot of new things about Gromit and I appreciate your feedback. Seems like everyone on this forum wants to help one another!

 

Don't muscle the ground wire connections though, just check they are firmly secure.

 

I actually experienced this a couple of days ago. Seemed like really lean.. and not going.. requiring extra gas pedal. Only thing different I did that time on startup.. I shut the car off during it's startup sequence and went back in the house because I forgot something. Usually I start the car and let it run by itself until the blue light goes off..... this time I interrupted this sequence. Might have something to do with it.. just me guessing.

 

Doesn't seem to have anything to do with the startup sequence. Usually happening to me when I'm 'hyper-milling' around town trying to save gas.
After a while just doesn't go.

 

Thanks, TrailAngel. Yea. This really is an odd one. I've tried most of the suggestions offereed in this thread, including the "Italian tune-up". So far, nothing I can put my finger on either. I even have a notebook in the car monitoring brand of gasoline, humidity, temperature. Something tells me that the brain of the engine senses something that is different. I just can't figure it out. And, as mentioned in my previous note, I had asked the dealer to investigate but, as mentioned, unless there's a distinct computer code, and...at the time of testing, the dealer really can't find anything.

Seems like some days, the little puppy really flies, but others...kind of like he's depressed and just doesn't want to move as well...less torque/push feel.

If you come up with anything, love to hear it and vice versa. Still - gotta love this vehicle!!!!

 

I wonder if the fuel pumps Subaru is using are a little inconsistent on fuel pressure and the draggy spells are from low fuel pressure events. Or if something else in the fuel line system is slightly reducing pressure in the fuel rails on each head?

 

I don't think it would be pressure related....unless controlled by the computer. It's as if the car has retuned itself.

 

All great thoughts and it does kind of feel like the car "retunes" itself, as TrailAngel suggests.

I'm thinking about purchasing a car diagnostic code reader (or whatever they're called) so that, if I can, output the data when Gromit is running well and when he's not. Then, if possible, compare the readings and see if I can learn anything from that then take that to the dealer.

I've never used a reader before. Does this sound like a decent idea and do you think it would be worth the expense? Would I get usable data? Is it easy to use?

Thanks all!!!

 

Just a thought - your mention of keeping a notebook of temp, humidity, gas, etc. made me think of it.
How about using a stopwatch or at least a second hand on a watch and keep tabs on acceleration say from 20-40 in second gear or 0-60. Doing it when things are normal and when things aren't normal.
All this wizzardly under the hood is hard for an old geezer to understand. The damn thing senses things and resets things all by itself apparently. Why can't we just adjust the ignition points (remember those?) with a knife blade and be on our way?
For those of you who just gagged....yes, my first car DID have a crank. But, it also had a self-starter. 1962 Peugeot 404.
:biggrin:

 

Hey, Shiftyguy. Thanks for your idea. In this case, though, the stopwatch method you suggest wouldn't, I don't think, help me figure out what's going on. The acceleration is not that much slower that I would pick up a difference on a stopwatch - it's all about the "feel" of how Gromit moves. While there is a tad more slowness, more pedal required, the main problem is where the car just feels like it's running super-lean as opposed to normal or "fully charged" with gas.

Yea. I remember when I could fix my own cars - I just recently departed with a chrome induction timing light, the best on the market - I knew I'd never use it again. The wizardry you talk about, Shriftyguy, without a computer anymore, it's hard for most of us, I'm sure. Thanks again.

 

Did it again yesterday... driving sluggiish. Like not power. It was 100 degrees out.

 

I think by lean you mean "rich". Because lean would knock, but rich wouldn't, and wouldn't throw a code either. If you really want to try something, go get a dyno on a "good" day and a "bad" day. :smile:

My guess is the Forester has a learning ECU, that adapts to your driving habits.

Does anyone know if anyone makes lightweight pulleys for the Forester? I put some on my S2000 and when I turned on the AC it felt like it didn't put as much stress on the engine.

 

^^Agreed, rich condition will make the car feel heavy and slow; leaner mixture would achieve greater power but too lean of a condition will generate too much heat and cause pre-ignition problems. Fuel starvation would make the car hesitate though, maybe you mean that. Timing too retarded will also take away power.

What octane are you guys running? I would try a full tank of highest available octane from a good station (Chevron here) and see if anything changes after 50 miles or so of filling up.

Stan

 

Last fill-up was Chevron 87....and was running good the previous day. Car has never knocked, even when putting the "pedal to the wire." Yes, I believe it is doing something like going rich and adjusting the timing due to heat.