95 Impreza 1.8 Lacking power

bangorfreeflow · 12-29-2011, 01:15 PM

Recently purchased my 4th 95 Impreza(1.8L). The car starts right up no problem, idles like a champ. But when you give it any more than quarter throttle it has absolutely no balls, and will not accelerate. It's hitching up, but never stalls.

I've already checked the fuel filter, and I know the first thing that's going to be recommended is plugs/wires, which I plan on getting today. I talked to a subaru guy in town, and he seems to think it's a dead spot in the throttle position sensor. These are 200$ new, and no junk yards in town have one, so I'm heasitant on buying it. I had a similar problem on another 95 wagon I had, which turned out to be a fuel pump, but it was more of either it worked 100%, or didn't work at all... used to beat on it with a hammer to unfreeze the dam thing when it would sputter/stall.

CEL is usually off, although sometimes will come on upon start, then go away. but when it's running/driving and still hitching there is no CEL. My local shop only has OBDII computers, I'm not sure where to find OBD I.

All input appriciated

* Registered users of the site do not see these ads.

Jessekrs123 · 12-29-2011, 02:34 PM

Are you sure it is a 95? I thought Subaru switched over to OBDII in 95?

Oh well, if it is OBDI then you will rarely get a CEL because unlike an OBDII car, there are no inefficiency codes except for when you are running lean. (I've had MANY OBDI Subarus and never got a lean code). Unless there is a failure within the electrical harness or the sensor has failed completely, no CEL will show.

You can pull stored codes using the black memory connectors under the steering column. It will flash the code numerically. Long flashes = 10, shorts = 1, short pause in between blinking means it has started a new code if applicable. Add them up and it should give you the code.

Here is a quick video I made which might be able to help you:

Diagnosing Your Subaru's Check Engine Light - YouTube

Testing the TPS is a little difficult. You can check for continuity when it is fully closed, and then the circuit opens up as the throttle opens up with the connector unplugged. (IIRC, it has been a while since I tested a TPS but I'm pretty sure that is how it works). You would have to probe the necessary prongs and hook up the connector to get accurate voltage readings which can be tricky if you're not too familiar with electrical testing. You can check for power and ground to your connectors as well, but if there is no CEL then I doubt there is a problem within your wiring.

Also is this Impreza an auto or a manual? I know my father's auto 2.2 is ridiculously doggy compared to my manual. The 1.8s lack power as it is.

Hope this helps.

bangorfreeflow · 12-29-2011, 11:02 PM

Hey! thanks for the input. I've got a 1.8 manual. I know they lack power as a 1.8, but nothing like this (this is my 4th 1.8 5-speed). I can rev the car fine through all the revs so long as I don't give it more than a quarter throttle, which is what makes me think it's the TPS... I'm thinking the Cat could be clogged too, and I really have no idea how to go about cleaning it out myself. Hopefully the bolts aren't corroded like crazy :X. I'll keep this updated as I find out more, would it be worth my time to check the coil pack? MAS? MAP? Coolant temp sensor?? I'm not too familiar with diagnosing this problem, unfortunatly.

bangorfreeflow · 01-11-2012, 02:04 PM

update: After installing a new TSP and cleaning the MAS, the car runs only slightly better. I've also added injector cleaner, but haven't gotten to drive the car much beyond the end of my road and back a couple of times since it's not registered. Anyway, today I went out to diagnose why the horn isn't working, and the car won't start. When I turn it over it sputters a tiny bit just at the start of the turn-over, then doesn't make any sign that it's trying to start. I checked the connections to the MAS and TPS to no avail.

Any ideas people?

Jessekrs123 · 01-11-2012, 02:18 PM

Did you check that ground? It sounds like you're having grounding issues.

bangorfreeflow · 01-11-2012, 02:32 PM

Could you elaborate? which ground are you refering to?

Jessekrs123 · 01-11-2012, 08:44 PM

Quote:

Originally Posted by bangorfreeflow

Could you elaborate? which ground are you refering to?

The main ground in the rear of the engine. Should be either on the back of the intake manifold or on the rear of the valve cover on the passenger side.

bangorfreeflow · 01-12-2012, 04:45 PM

After diagnosing the CEL as described above I come up with codes:

injectors 1-4
MAF sensor circuit
Idle Control System Malfunction
Engine Coolant temperature sensor
throttle position sensor circuit
Turbine speed signal

I have a hard time believing that each one of these is at fault... How should I go about approaching this?

bangorfreeflow · 06-06-2012, 07:30 PM

I've still yet to figure out what's wrong with this!! My friend seems to think the O2 sensor is bad. I also heard that I can simply unplug it and it will run fine if that's the case. Which o2 sensor should I look at, and how should I diagnose it?

12-29-2011, 01:15 PM	#1
bangorfreeflow Scooby Newbie Member#: 305275 Join Date: Dec 2011	95 Impreza 1.8 Lacking power Recently purchased my 4th 95 Impreza(1.8L). The car starts right up no problem, idles like a champ. But when you give it any more than quarter throttle it has absolutely no balls, and will not accelerate. It's hitching up, but never stalls. I've already checked the fuel filter, and I know the first thing that's going to be recommended is plugs/wires, which I plan on getting today. I talked to a subaru guy in town, and he seems to think it's a dead spot in the throttle position sensor. These are 200$ new, and no junk yards in town have one, so I'm heasitant on buying it. I had a similar problem on another 95 wagon I had, which turned out to be a fuel pump, but it was more of either it worked 100%, or didn't work at all... used to beat on it with a hammer to unfreeze the dam thing when it would sputter/stall. CEL is usually off, although sometimes will come on upon start, then go away. but when it's running/driving and still hitching there is no CEL. My local shop only has OBDII computers, I'm not sure where to find OBD I. All input appriciated * Registered users of the site do not see these ads.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
New Member W/ Power Steering Problem 95 impreza 1.8	rob17san	Normally Aspirated Powertrain	1	10-01-2010 02:19 AM
Diagrams: Underhood Fuse Box Circuit, 95 Impreza 1.8	t3hWIT	Electrical & Lighting	0	01-17-2007 07:18 PM
95 impreza 1.8 to jdm ej2.0t help!	dooba33	Subaru Conversions	21	05-28-2006 01:50 AM
95 Impreza 1.8 suddenly not running right	Impretzle	Normally Aspirated Powertrain	14	01-31-2006 06:45 PM
Will a wrx aftermarket exhaust fit on a 95 impreza 1.8	NewbyScooby	Normally Aspirated Powertrain	3	05-22-2003 03:32 AM

12-29-2011, 11:02 PM	#3
bangorfreeflow Scooby Newbie Member#: 305275 Join Date: Dec 2011	Hey! thanks for the input. I've got a 1.8 manual. I know they lack power as a 1.8, but nothing like this (this is my 4th 1.8 5-speed). I can rev the car fine through all the revs so long as I don't give it more than a quarter throttle, which is what makes me think it's the TPS... I'm thinking the Cat could be clogged too, and I really have no idea how to go about cleaning it out myself. Hopefully the bolts aren't corroded like crazy :X. I'll keep this updated as I find out more, would it be worth my time to check the coil pack? MAS? MAP? Coolant temp sensor?? I'm not too familiar with diagnosing this problem, unfortunatly.

01-11-2012, 02:04 PM	#4
bangorfreeflow Scooby Newbie Member#: 305275 Join Date: Dec 2011	update: After installing a new TSP and cleaning the MAS, the car runs only slightly better. I've also added injector cleaner, but haven't gotten to drive the car much beyond the end of my road and back a couple of times since it's not registered. Anyway, today I went out to diagnose why the horn isn't working, and the car won't start. When I turn it over it sputters a tiny bit just at the start of the turn-over, then doesn't make any sign that it's trying to start. I checked the connections to the MAS and TPS to no avail. Any ideas people?

01-11-2012, 02:18 PM	#5
Jessekrs123 Scooby Specialist Member#: 236927 Join Date: Jan 2010 Chapter/Region: NESIC Location: Oakville CT Vehicle: 1993 Legacy Sedan 1984 BRAT	Did you check that ground? It sounds like you're having grounding issues.

01-11-2012, 02:32 PM	#6
bangorfreeflow Scooby Newbie Member#: 305275 Join Date: Dec 2011	Could you elaborate? which ground are you refering to?

01-12-2012, 04:45 PM	#8
bangorfreeflow Scooby Newbie Member#: 305275 Join Date: Dec 2011	After diagnosing the CEL as described above I come up with codes: injectors 1-4 MAF sensor circuit Idle Control System Malfunction Engine Coolant temperature sensor throttle position sensor circuit Turbine speed signal I have a hard time believing that each one of these is at fault... How should I go about approaching this?

06-06-2012, 07:30 PM	#9
bangorfreeflow Scooby Newbie Member#: 305275 Join Date: Dec 2011	I've still yet to figure out what's wrong with this!! My friend seems to think the O2 sensor is bad. I also heard that I can simply unplug it and it will run fine if that's the case. Which o2 sensor should I look at, and how should I diagnose it?