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98 legacy speed sensors? Help


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I just bought a 98 subaru legacy gt 2.5 for cheap because of trans problems and now i am trying to fix. The CEL and ABS lights are on. Codes are p0303 po304 p0325 p0500 p1507 p1540  . So i know 302 and 303 are knock sensors and i also know that the car is very low on oil. Would those go hand in hand? Now for the tricky part the speed senors and abs codes. There is no speedometer and the rear wheels is not spinning so there is a good chance with the codes is speed sensors right? I also read where one bad speed sensor will throw both of the sensor codes? I am lost on this one and does the sensors go to the same place as in electrical? I know this type of thread is everywhere but i can not get specific answer on what i am suppose to be looking at. This is my first Subaru so  i do not have that much knowledge on Subaru. 

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So i keep digging at this problems and if i am right the speed sensors send a signal straight to the console then to the ECU? So if am thinking right the ground wire on the console could be the problem in all? More background came to light. The previous owner was traveling down the interstate when the car  started acting up and shifting bad. My orginal thought was it was the clutches 

 

BTW ITS A AUTOMATIC TRANSMISSION. 

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welcome.  i'll be in Oak Hill tomorrow!

 

1.  fill the oil up.

2.  clean both battery terminals and make sure they're clean, tigth, and good.  checking visible grounds would be wise too.

 

with all those issues you may simply have low voltages issues everywhere screwing up the signals.

 

if it's not that your best bet is to clear the codes and see which one comes back first.

start the car - and as soon as you see the check engine light, read the codes and see which one came back first.

 

get a code reader for $35 on ebay/amazon or have Advance Auto, Autozone, etc clear them for free, or disconnect your battery cable for 20 minutes, that should clear them.

 

P0325 is knock sensor.  normally the sensors just crack at the base and need replaced.  Ebay = $15 new knock sensors

 

303 and 304 are misfire codes.  in general, in order of most common causes for misfires

1.  OEM NGK plugs

2.  Subaru or at least high quality wires, these engines aren't forgiving otherwise

3.  Coil pack

4. Igniter

5. Major engine issues

 

P01507 and 1540 I would assume are a phantom or a result of the others/stalling/etc. Rare code, i'd focus on this one later unless there's a compelling reason otherwise...obviously we know little of the car and it could have all sorts of things going on.

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So here is a update I did a little tuning then reset the ecu and the only code I got was for a knock sensor po325 so I check the continuity for that sensor at the sensor and it tested good also the continuity for the wire was also good. So with all of the previous codes do you think it really could be a knock or am I missing something? Also the rear wheels still is not spinning no speedometer either so I am clueless what to do.

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so I learned a few things searching the web and I figured out I made a rookie mistake. Apparently this type of engine has a small knock when it gets really cold out. That got me thinking I never let it get warmed up to running temperature. so I replaced the knock sensor and now I have narrowed down to the problem the original owner was talking about. I drove it a little and still no check engine light. after driving the car and when at a stop it sounds like something is grinding in the transmission anytime it is stopped but when going the car sounds fine but it has a slight delay(3-5 seconds) in switching gears. Also still no speedometer and rear wheels still not spinning. So I am thinking that the converter in the tranny is getting ready to go out or transmission change. What do you all think?

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I read about the TC not seated right will cause noises from the torque converter like i am describing. The only question  is would that cause the speed sensor not to work. I would not think so but i am not a Subaru expert either so once again can someone give me more information?

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If the TC were seated incorrectly the trans fluid pump would be damaged and the trans would not work at all.

 

No rear drive could be because someone put a fuse in the FWD fuse holder on the passenger strut tower.

Or it could be because someone removed the rear section of the driveshaft.

 

No speedometer might be the speed sensor on the side of the trans, might be the speed sensor drive gears inside the trans (not easily replaceable), or could be the speedometer head itself. Some 98 and 99 models had a problem with a ground on the PCB on the speedometer head. I would start there.

The speedometer does not get any signal from the ABS wheel speed sensors, only from the speed sensor on the side of the trans.

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A fuse in the FWD fuse holder, or removal of rear section of the drive shaft may have been done if there was torque bind. If torque bind was that bad, then going to FWD only may have been the better option. Seems like there is a lot to get sorted out on this car.

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Thanks for your reply and there is no fuse in the passenger strut already checked i will check the dash head tonight and if that fixes the speed o then i am going to put the fuse in the fwd. I have to have this car ready for the highway by Monday. 

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I don't know how accurate of a test this is but I places a drill on the end of the speed sensor and we both turned the key on and also started the car and will the speed sensor was spinning the speedometer was not. We also had the speedometer out so we could wiggle the wires going into and still nothing. Althought the speed sensor felt like there was resistance in the magnet so I fell like that is not a problem. I ordered a new one and its suppose to be in today so I am going to hook it up and see if that is the problem. So would a tired clutch pack or dash head cause a CEL? 

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Problem is not wiring in the speedo head, its a broken solder joint or trace on the PCB. There is a good thread with pics on how to fix it out there in google-land somewhere.

This problem will set a CEL because the speedo head sends speed signal to the ECU.

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so if i dont have a check engine light that means the signal from speedo is coming straight into it and the leaving to the ecu. No speedo but  apprantley the signal is getting to the ecu so its not settin off a CEL. I am so confused. The light comes on when to start so i know the light works. Well there must be a CEL unless the speedo gear in the transmission is bad but that does not help that the speedo does not work. i guess i will clear the ecu and see what codes pop up when i finish

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