Performance Issues : Subaru Legacy 1996 Wagon TS-R

[Damien Hill]

Hi Guys, I have had a 1996 Subaru Legacy brought to me, which I have worked on once before… The problem I have is the car starts and runs perfectly, transmission is shifting through the gears fine also. HOWEVER, soon as we hit the road for a drive the problems persist.

The first problem the car is having, is when you accelerate off when cold, it just doesn’t have that pull it should have (restricted type feeling) as when you start of accelerating up a hill it wont respond like it should unless you plant the gas pedal it gets some revs..

The second problem I have is when your sitting on the highway at 100km/h its running perfectly, however as soon as you get some resistance on the engine (such as a gradual uphill gradient) the car starts to give a miss while still maintaining that 100km/h mark. Now what I mean by a miss, is not completely misfiring, but very quick surges which you can feel. but when the road is flat it seems fine.

The part I am stuck on is these problems could both be related.

I just want your guys input as well as mine, as it all helps to have more than one head against this.

The things I have checked…

–> Air Filter / MAF Sensor
–> Oil Level
–> Coolant Level
–> Transmission DipStick
–> Spark Plugs

All of the above are perfect.

Things I am yet to complete:

–> Compression Test
–> Change the Fuel Filter
–> Check the Injectors

Any more ideas would be fantastic.

Many Thanks!

Topic

[ScannerDanner]

it does sound like a fuel delivery issue. do you have access to a scan tool?
if you do a test drive at WOT while watching the O2 sensor mv reading would be a great direction based test. It should stay rich (over 800mv) the entire time you are at WOT. If it does then we move away from a fuel delivery issue. If it drops lean, then we have a fuel delivery issue and our focus will then go toward fuel pressure and the MAF sensor.

(faulty MAF sensors are common on this year Subaru)

[EricTheCarGuy]

Actually I’ve gone through this process on my own car.

Solving Performance Problems 1

Solving Performance Problems 2

Re Performance Problems

[Damien Hill]

Thanks for the reply Eric, I have been following your progress when you got that car. I did replace the Fuel Filter and I did actually notice a difference. However I still have a slight miss at high speed under load on a slight rise on the highway. Very quick miss, but not enough to call it a miss fire miss fire, if you get what I mean here. Could I start looking at the ignition coil, the ignitor or the leads? are they something to start with you would consider? Cheers

[EricTheCarGuy]

As pointed out in the above videos I have a transmission problem. You’ve spent some time and effort on the engine but don’t rule out a transmission issue.

[Author]

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