[Tree Muncher]

My 03 has a bad skip/surge around 3000 rpm's. It is most noticeable in 3rd gear at a medium to medium hard acceleration, matters not if it's hot or cold, but it does not do it every time. Generally, the turbo gauge will jump to nearly 0.1 MPa and then flutter up and down a couple of times when this skip occurs. Is anyone else experiencing this problem?

I've had it to the dealer three times already. They replaced the fuel pressure regulator and called it fixed. It still did it on the way home but not as bad. This week, the service manager had me try a brand new wrx w/ 9 miles on it. That one has the exact same skip also.

The gear does not make the difference. Third gear just does not accelerate as fast as first and second and does not put me into "radar hot zone" as fast as fourth or fifth.

 

[Retro]

Well, 3rd should not be able to accellerate as fast as 1st or 2nd unless 1'st or 2nd are weakened. Third gear on mine definitely pulls though if I'm comming off of 2nd in at least 5krpms.

 

[Tree Muncher]

Retro, I think you somehow missed the whole point of the post. It is the surging problem I'm concerned about. Do you have the same problem with the surge/hesitation/skip/misfiring or whatever else you might like to call it?

I'm interested in fixing this situation ( the surging and skipping ) and I'm looking for others who may have had the same problem and how they got it fixed.

Yes, it will do it in the other gears but it is less noticable in 1st or 2nd because it blows through those gears so quickly.

 

[Trypsin]

MIne does, has since the day i bought it.
I think some people have done the grounding mod for this, i just live with it.
Mine will really take off around 5200, like a 2-stroke in the power band.
Just hesitates/misses in the lower rpm usually at full throttle.

 

[TRex]

I encounter the same problem on occasion. It just seems hard to believe they would have a bug that bad in the fuel mapping unless it was intentionally trying to do something.

I have wondered if it's the engine trying to avoid detonation. The same reasoning as to why our cars sometimes feel like dogs, but very strong on other days. Maybe inefficiencies in the intercooler?

Just drive around at 5,000rpm and you'll be fine.

 

[PKer]

Try the grounding mod.

 

[KanosWRX]

I had a little bit of what you had, did the grounding mod and it smoothed everything out. Might also want to look into intercooler hoses, those help too.

 

[SC_Compact]

I have an 03 WRX wagon and I have the same problem at 2800 rpm. I figure it is just something that I will have to live with.

 

[Tree Muncher]

Many thanks to all of you who took the time to respond to this inquiry. This is what makes the internet and these forums great.

I'll be sure to try the grounding modifications and see if that solves the problem. In the meantime, the dealer is supposed to check with the factory rep to see what they can find. I plan to keep this car for a long time and I will never be satisfied to live with this problem being that I purchased it new. None of us should have this problem with a new car to begin with.

On a tangent; my wife has been so jealous of the Subaru and the way it drives that we had to go out and buy her a used Forester yesterday. No more bi*chin' Anyone in the market for a '90 Honda Civic Si?

 

[blip]

Really interesting to read that so many of you also have this surging/stuttering in the power delivery. I have exactly the same thing on my UK 04 WRX and it's really starting to bug me now. I put up a similar message on a UK Subaru forum and got hardly anyone else with the same problem. Thanks guys, at least I know now I'm not imagining it!!

I had the Prodrive Performance Pack (PPP) fitted to my WRX at the 1000 mile service and only really started to notice the flat spots after that. I'm not sure if you have the Prodrive Pack over there but basically it is a new ECU, faster flowing backbox/cat and larger intercooler hose. It is really popular over here as it is still covered by the Subaru warranty, but hikes the power up to 265bhp and gives it more torque than an STi. Recently an 04 WRX with PPP got a 5 star rating in one of our best performance car mags - Evo. So I assumed it would be the muts!

I initially assumed that the surging problem was something to do with the Prodrive Pack, but after reading your posts I think it is a more fundamental problem with the WRX. Either way it is really annoying as this is my first Impreza, I waited a long time for it and it cost me a lot of my hard-earned cash.

I not only feel several flat spots when accelerating hard between 2800rpm and 4500rpm, but also notice them if I try to cruise steadily at certain revs, or creep up slowly through the rev range. I also get very abrupt surging when decelerating, or if I lift off slightly during hard acceleration. When this happens it's a severe lunge as if all power is cut (makes my head jerk forward) even though I may only be lifting off the gas very slightly. Get it bad if I accelerate to 5500rpm and then lift. Never had this in any other car, it's as if there is no progression into smooth engine braking.

I am tempted to try the grounding mod but it does seem from all the posts I've read about it that a lot of you guys find that any benefit wears off after a couple of weeks once the ECU has retuned itself, and that the initial improvement is purely down to having disconnected the battery and resetting the ECU. Anyone actually had a long term improvement from the grounding mod?

BTW this is a really cool forum!

 

[Retro]

About the acceleration in 3rd, I was just trying to clear up what was said in the first post, as it seems odd. As for the surging/hesitation feeling I have that too, but mostly in 2nd under hard acceleration. Around 2800 - 4krpms I get these little tuggs and bumps that at first feel like the road, but occur too much and at the same strength over different roads. I tried the grounding mod also and it did nothing to smooth it out, so I just suspect it is the fueling or something being adjusted by the computer.

 

[vanguard]

I have a similar problem at 4500-5000rpm. settled on that it must be an ECU quirk- got that reinforced if a Rex with 9 miles did it. Anyway, mine felt like a fuel cut. You can get a fuel cut defender or lifter (MRT/HKS) which some adjust to specific rpm ranges. I read an article where the DSM Gallant turbo suffers fuel cut in a similar rpm range- so I read my CEL codes and two codes came up:

One was MAF sensor didn't like what it read (other was overboost when :dialing in" my Greddy MBC). The MAF sensor apparently trips my CEL light regularly and my guess is that the ECU cuts fuel in defense of this read.

 

[Tree Muncher]

Partial grounding mod performed

This morning I installed my first grounding mod and things have become worse. I have not made the entire modification, yet. I only ran a line from the battery to the right intake grounding lug. I only had one set of lugs to start this mod. I also used some anti-corrosion agent used to ensure good grounding on aluminum connections (Lowe's electrical dept. for the agent ).

As of this afternoon, I can not get more than .85 - .90 MPa on the gage. It always put out 1.0 MPa prior to the mod but then today is very humid and quite warm so the air will not be as dense as other days. Previously, I never noticed the weather making any change to the skipping/surging problem. As for the battery disconnection resetting the ECU, that was only pulled for a maximum of 10 minutes. I thought it took 45 min or longer to reset the ECU?

The mod has not changed the surge problem at all. I have noticed the increased humidity has coincided with the increased amount of surging from the engine. I will try grounding to another location and see if it makes any other changes.

I love the way the car drives but I really hate this surge problem!

 

[DangerousGrafix]

surging

i never experienced the surging while the car was stock, i installed the bosal 3" w/dp, a K&N cold air, GFB pulley kit, GFB adjustable BOV and a turbo xs computer set at 3.

i recently put the car back to stock with the exception of the pulleykit and BOV and the car surges under hard acceleration (like getting on the freeway or passing another vehicle).

it surges bad. you put your foot to the floor and it goes and slows, goes and slows. cant figure it out.

Bueller? Bueller?

 

[ak_wrx]

My car surged when i first bought it. Did it bad on the test drive but after i drove it for about a day it got much better. But i still do feel it everyonce in a while. Kinda annoying.

 

[hakira]

the dead is resurrected!!!!!!!!!!!!!!!!!!!!!!!

 

[lucabrasimd92]

My 03 has a bad skip/surge around 3000 rpm's. It is most noticeable in 3rd gear at a medium to medium hard acceleration, matters not if it's hot or cold, but it does not do it every time. Generally, the turbo gauge will jump to nearly 0.1 MPa and then flutter up and down a couple of times when this skip occurs. Is anyone else experiencing this problem?

I've had it to the dealer three times already. They replaced the fuel pressure regulator and called it fixed. It still did it on the way home but not as bad. This week, the service manager had me try a brand new wrx w/ 9 miles on it. That one has the exact same skip also.

The gear does not make the difference. Third gear just does not accelerate as fast as first and second and does not put me into "radar hot zone" as fast as fourth or fifth.

I have the same problem on my 2008 sti hatch.
My car intermittently in hesitates and cuts out once I get over quarter to half throttle and the engine is around 2800-3000
I know the 08 sti's had a bit of hesitation at that rpm range and it has to do with the factory tune to get the car to pass emissions.
It seems to be worse when I have it in intelligent mode
The car is on an open source tune and it's running around 16psi of boost with a cobb intake, turbo RS intercooler, invidia down pipe and full exhaust.
Yesterday while I was on my way home from work the car started hesitating at about 70mph and 2800 rpm. It got worse as I got into town everytime I would take off from a light it would start cutting out when under load it also died on me once but I was able to start it back up.
From what I've read it sounds like a fuel issue
either the fuel pump is going out, I got bad gas and it clogged the filter that is on top of the pump or the fuel regulator is not working properly.
The car has 61,400 some miles and subaru recommends doing the fuel filter at 60,000 miles.
Also my fuel gauge reads 3/4 when it's full and when it's on 3/8 of a tank the car still has about 10.7 gallons left in it.
I'm still doing my best to diagnose the problem so any thoughts or advice will be helpful