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If you say so.
00' 2.5RS Coupe, 70' TLC
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699 Posts
Discussion Starter #1
After a ton of reading on this site and online in general, I now need to ask for help for my stalling problem.

Car stats: MY00 RS, AT with over 200,000 miles. Oil change and PCV changed at 200k mark.

Here's what's going on:

When I head out to work in the morning, I start the car and I'll let it idle for 1 minute. I start driving and come to a stop sign. No issues. I drive for about half a mile at 25mph, because its a residential area. Then I come to another stop sign where I make a left. The road then becomes a highway where I reach a speeds of 55mph. By this time the car is fully warmed up. 1.5 miles down the road I come to a traffic light where I make a right turn. Usually at this light is where I need to come to a dead stop from 55mph. This is also the spot where my car will stall. After I crank her back up, everything will be fine. There's another traffic light 3 miles down the highway and she will not stall or have any issues.

This will also happen during lunch time if I decide to get leave work to grab a bite. Same thing happens when the car fully warms up. She will stall at the first stop sign or traffic light.

I also notice that it doesn't matter what the temperature is outside because this started happening in the Summer months. It also doesn't matter whether the fuel tank is full, half or at the quarter mark.

I did read the "Hesitation" thread and changed out my fuel filter, spark plugs(gapped properly of course), spark plug wires, knock sensor, front and rear O2 sensors, cleaned out and checked the IACV, changed the fuel pressure regulator and added a can of Royal Purple Fuel System Cleaner.

My fuel pump is fine because I can hear the 2 second buzz when I turn the ignition to the "ON" position. This is the only part on the car I haven't changed since I'm thinking its a fuel or electrical issue.

I do have a Scanguage 2 hooked up to my car and it will pop up with code P0420. After a lot of reading a lot of people suggested that I change out the Catalytic Converter or the front O2 because either one or both are bad.

I've gone through 3 front O2 sensors in the past 6-8months. I also bought a used Catalytic Converter from a good member here. He used the same CC to smog his car before he did his WRX swap. After using the "good" CC and a new front O2, I still get the P0420 and the car still stalls when coming to a stop.

With all that said, I still think its an electrical or fuel delivery issue.

What do you think it is? Is there anything I missed?
 

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00 BE, 92 BC, 77 celica GT
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2,192 Posts
It sounds more like a torque converter issue with the auto trans unfortunately...
 

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00 BE, 92 BC, 77 celica GT
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2,192 Posts
If it was the torque converter, then wouldn't the car stall more frequently?
Pop the car into neutral when you're coming to a stop tomorrow. Does it stall?
 

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The subaru of many acronyms
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1,919 Posts
only reason it would be stalling from higher speeds is that your TC will lock up once its in OD and engages torque convertor lockup. TC lockup wont engage unless your cruising in high gear and the tranny has reached operating temp. check your brakes to make sure the lights are lighting up when you hit the brakes, go through and check all the connections for the brake switch thats my guess where the fault is.
 

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00 BE, 92 BC, 77 celica GT
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2,192 Posts
only reason it would be stalling from higher speeds is that your TC will lock up once its in OD and engages torque convertor lockup. TC lockup wont engage unless your cruising in high gear and the tranny has reached operating temp. check your brakes to make sure the lights are lighting up when you hit the brakes, go through and check all the connections for the brake switch thats my guess where the fault is.
This. Brake switch is number one reason after fluid level or condition for torque converter not coming out of lockup.
 

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If you say so.
00' 2.5RS Coupe, 70' TLC
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699 Posts
Discussion Starter #8 (Edited)
I'm sorry guys, but where do I find the brake switch?
I'm 100 percent sure that all my lights light up when I hit the brake, but I will double check just to make sure.
 

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2000 2.5RS/C BRP
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2,321 Posts
The brake pedal switch has two circuits through it, the lighting circuit and the cruise control/Auto signal wire, so the lights working doesn't necessarily mean your switch is good.

The switch is a bit of a pain to get to... The easiest way is to slide the driver's seat all the way back, fold the back all the way down, then lay on it backwards. Lay your head on the carpet at the pedals, it should be obvious at that point.

Find your wiring diagram before hand, you might be able to find a different spot to check the wiring that doesn't require Cirque du Soleil levels of flexibility to be useful...
Impreza Manuals | ken-gilbert.com
 

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00 BE, 92 BC, 77 celica GT
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2,192 Posts
Are all your vacuum hoses securely connected to your torque box?
There's no vacuum hoses to the torque box, as theres never any vacuum present there. Vacuum for the booster comes off the drivers side of the intake manifold.
 

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If you say so.
00' 2.5RS Coupe, 70' TLC
Joined
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699 Posts
Discussion Starter #13
Pop the car into neutral when you're coming to a stop tomorrow. Does it stall?
Sorry I didn't respond any sooner, but work was busy with year end celebrations and such. Anyway, the answer to your question is "no". The car does not stall when I pop into neutral, when coming to a stop from 55mph.
 

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If you say so.
00' 2.5RS Coupe, 70' TLC
Joined
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699 Posts
Discussion Starter #14
only reason it would be stalling from higher speeds is that your TC will lock up once its in OD and engages torque convertor lockup. TC lockup wont engage unless your cruising in high gear and the tranny has reached operating temp. check your brakes to make sure the lights are lighting up when you hit the brakes, go through and check all the connections for the brake switch thats my guess where the fault is.
Sorry I'm just responding now. The brake lights do light up.
 

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If you say so.
00' 2.5RS Coupe, 70' TLC
Joined
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699 Posts
Discussion Starter #15
The brake pedal switch has two circuits through it, the lighting circuit and the cruise control/Auto signal wire, so the lights working doesn't necessarily mean your switch is good.

The switch is a bit of a pain to get to... The easiest way is to slide the driver's seat all the way back, fold the back all the way down, then lay on it backwards. Lay your head on the carpet at the pedals, it should be obvious at that point.

Find your wiring diagram before hand, you might be able to find a different spot to check the wiring that doesn't require Cirque du Soleil levels of flexibility to be useful...
Impreza Manuals | ken-gilbert.com
Is there a way to test out the cruise control/Auto signal circuit with a Multimeter?

Also, now that you mention it. For a long time its been very hard to set my cruise control. What I mean by this is I have to hold down the knob for at least 5 seconds before Cruise Control engages.
 

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2000 2.5RS/C BRP
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2,321 Posts
Is there a way to test out the cruise control/Auto signal circuit with a Multimeter?

Also, now that you mention it. For a long time its been very hard to set my cruise control. What I mean by this is I have to hold down the knob for at least 5 seconds before Cruise Control engages.
Sounds like the switch might be going. It's effectively two switches in one, so one half can get broken. A friend's 95 Legacy L has that problem.

For testing, yes. I don't know which two pins you'd want to check, you need to determine that from the wiring diagram, but you would disconnect the connector and put one lead from the multimeter on one of the two contacts on the switch, the other on the other. The multimeter should be set to resistance. I'm guessing (you can confirm with your wiring diagram) that the switch should close when the pedal is pressed, so normally the multimeter should read INF or 1 depending on how it displays open circuit. When the pedal is pressed, it should display a number, ideally very close to zero. If it doesn't, you're either reading the wrong pins or the switch is broken.
 

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00 BE, 92 BC, 77 celica GT
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2,192 Posts
Yep. Its a simple open closed switch. Sounds like TC lockup issues as shifting to neutral prevents the stall. I would definitely start with the switch.. or a potentially bad trans ground
 

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If you say so.
00' 2.5RS Coupe, 70' TLC
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699 Posts
Discussion Starter #18 (Edited)
I did change out the trans fluid on it too. I dropped the pan and changed out the internal strainer type filter and the spin on filter. From doing some research I knew that the pan had a donut magnet inside it. I was looking for anything abnormal, like large chunks of metal, but didn't find any. All I saw were some fine metal particles attached(looked more like goop) to the magnet itself.

7 quarts of synthetic ATF later, my car does shift much smoother.
 

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If you say so.
00' 2.5RS Coupe, 70' TLC
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699 Posts
Discussion Starter #19
*****UPDATE*****

Sorry for the long delay in responding again.

I changed out the Brake Switch and still the same thing is happening. I'm convinced this issue is from the Torque Converter. Since I found out I also have a small oil leak coming from my head gaskets, I will probably end up removing the engine to fix the small oil leak since I've read this is related to my constant P0420 issue.

Since the engine will be out I am going to replace the TC as well.

Does anyone know where I can get a low mileage or a re manufactured unit for a good price?
 

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00 BE, 92 BC, 77 celica GT
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2,192 Posts
I use LKQ for all my used parts. They have a pretty good reman program as well
 
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