2.5i No throttle HELP!!!!

I know this is a GT forum but I have been a lurker on this forum for a while, Today I was accelerating from a stoplight when I noticed the throttle wasn't registering on my tach. No response/no acceleration. Had to coast it to the side of the road via idle. When I got to the side I put it in park and it idled high (approx 2000 RPM). When in gear it dropped way down to normal or below normal RPM's. I got out googled it on my phone and saw someone do the lock unlock trick. This got it running and back home --> idle seemed to be normal. The check engine light has been on for a couple weeks now (nearest dealer is an hour away and im busy with school) I just haven't had the time to get over and get it looked at. Does anyone have any clues to what this might be? Think it will make it an hour to the dealership? What kind of problems should I be expecting. Thanks for the help

It sounds to me like part of the drive by wire setup. Either the sender at the gas pedal, or the throttle body. The codes should have the details.

 

Whats the lock/unlock trick ?

Just from a google search it came up with a guy that had similar problems. He said he did the "lock unlock" trick so I got out and locked and unlocked it. Sure enough the throttle was back and I was able to get it home. Assuming its some kind of computer reset type of thing? Just glad it got me home and I was able to avoid towing it. I'm going to go get the codes pulled now.

pulled the following codes

 

1) P2097 -> post catalyst fuel trim system too rich

2) P0031 -> heater control circuit low voltage

3) P2138 -> Throttle Posistion Sensor "D"/"E" voltage correlation

4) P0131 -> O2 Circuit low voltage

 

The TPS is the code that probably led to whatever happened last night. Is the O2 circuit something to worry about? I'm going to get it checked out ASAP but I would like your guys thoughts on what it could be, so I don't go in blind to a car dealer an hour away.

Sounds like a bad upstream oxygen sensor. Instead of paying subaru around $100 to diagnose the problem, I would just replace the sensor for the same price and go from there. Fred Beans sells OEM for around $120 (MSRP $159, your local dealer could sell the sensor for a little more or less than $159), or rockauto.com has a Denso sensor for $97, which is supposed to be OEM quality.

Thanks I got one coming gonna hopefully put it on tomorrow if it doesn't rain. Really hope this fixes the stumbling/bad fuel economy. Still not sure what caused the no throttle issue best I could find on here was to use some electric contact cleaner on the TPS. So I tried that we will see if the problem creeps up again at all. Thanks for the input!

No problem. p2097, p0031, p0131 all point to the upstream oxygen sensor. Some might say p2097 means the rear sensor, but I've read a number of people replaced the rear sensor after getting p2097 and it did nothing, it makes more sense that the front is to blame anyways.

 

After doing more research on p2138, it appears that when this happens the car goes into limp mode, which it sounds like you experienced. It looks like an oem throttle position sensor has a msrp of around $120, with aftermarket sensors ranging from $48-$85 @ rockauto. It's weird though, the FSM says "Throttle body is a non-disassembled part, so do not remove the throttle position sensor from throttle body."

 

It's interesting though, some people in the links below report the problem being at the gas pedal assembly, possibly a loose connector there. I would recommend disconnecting and reconnecting the connector at the gas pedal (and inspecting/cleaning inside the connector). It looks like the connector is towards the top/front of the pedal assembly, as shown in the first link below.

http://i.ebayimg.com/t/05-OUTBACK-LEGACY-DRIVE-BY-WIRE-ACCELERATOR-PEDAL-PART-36010AG021-/00/s/MTA4MFgxNDQw/$(KGrHqRHJFEE+VtLppjzBQE-uD8how~~60_57.JPG

 

A few p2138 links. They aren't all legacy links, but I've found that CEL code problems and fixes are often very similar across other subaru models.

http://legacygt.com/forums/showthread.php/p2138-throttle-pedal-position-sensor-switch-150344.html

http://forums.nasioc.com/forums/showthread.php?t=803788

http://www.subaruoutback.org/forums/66-problems-maintenance/24906-code-p2138-throttle-position-sensor.html

 

Part of me is wondering, could the TPS/accelerator pedal connector issue have caused the other 3 CEL's? I really don't think that it would, I think that these are two separate issues. Doesn't hurt to replace the oxygen sensor anyways if your car is a 2005 and it still has the original.

Good call on the o2 sensor apexi! No more CEL I am pumped!!! I guess I'll just have to wait and see if the TPS code will creep up again but as of now I am excited to have a cruise control and no engine light!

did your p2138 issue ever come back? Having some frustrating issues of my own at the moment with the same problem car dumps into limp mode, blinking cruise light and engine light on.

No it never did, I did what apexi mentioned previously. I disconnected the sensor connected to the gas pedal and sprayed the connector with electrical contact cleaner and reconnected. It has worked fine ever since. Best of luck!

Glad to hear it worked for you, hope you never have to deal with it again because this is ridiculous!

 

I blew mine out with air, and reseated, didn't actually use the electrical contact cleaner, not sure if it would matter or not, but I'm willing to give anything a shot at this point as I try different things