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loss of power - sudden burst of power - repeat

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do a vacuum test. my aunts OBS had the same problem and it ended up being a cracked manifold if i remember correctly

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  • do not use stop leak products in your Subaru. See my post above...

  • I would have done the relay first because the MAF sensor and fuel injectors do not work correctly without the proper voltage. One down. Just the other day I had to replace the new MAF bought in A

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  • Author

So. I replaced the hose - throttle body to heater hose tubing (T juncture) - no more leak at hose. But very slow drip somewhere along heater hose (T juncture) tubing to point it ties into bigger heather hose tubing. Looks like a nightmare to replace the heater hose tubing - I think I would have to remove the intake manifold and timing belt cover and more to replace it - I don't know if it bolts in is pressed in, etc. It's such a small slow leak I may leave it alone for now. What do you guys think of leak stop (black pellets in a bottle) as a temporary fix? Or another product? 

_________________________________________

I located 2nd fuse box passenger side below glove box - but still not sure which resistor to replace. I also found resistors next to fusebox under dash on drivers side. Pictures attached. Which one is Main resistor? 

Thanks,

MiltyFuseboxPassenger.thumb.jpg.300a9bf94a826e75d070be8a9e478a67.jpgFuseBoxDriver.thumb.jpg.48232b4704aed49c0f20c1b1fc5e0d57.jpg

 

 

  • Author

So. I replaced the hose - throttle body to heater hose tubing (T juncture) - no more leak at hose. But very slow drip somewhere along heater hose (T juncture) tubing to point it ties into bigger heather hose tubing. Looks like a nightmare to replace the heater hose tubing - I think I would have to remove the intake manifold and timing belt cover and more to replace it - I don't know if it bolts in is pressed in, etc. It's such a small slow leak I may leave it alone for now. What do you guys think of leak stop (black pellets in a bottle) as a temporary fix? Or another product? 

_________________________________________

I located 2nd fuse box passenger side below glove box - but still not sure which resistor to replace. I also found resistors next to fusebox under dash on drivers side. Pictures attached. Which one is Main resistor? 

Thanks,

MiltyFuseboxPassenger.thumb.jpg.300a9bf94a826e75d070be8a9e478a67.jpgFuseBoxDriver.thumb.jpg.48232b4704aed49c0f20c1b1fc5e0d57.jpg

 

 

The Main Relay is located in the upper righthand corner of the relay block.

FuseboxPassenger.jpg

Or another product? 

many folks have good luck with the Subaru Coolant Conditioner (repackagaed Holt's RadWeld)

ONLY one bottle, ONLY install per directions.

81v3DGfLsmL._SY879_.jpg

do not use stop leak products!

If that tube is leaking, you will want to replace sooner rather than later - that small leak will turn into a large one very quickly on you.

the tube is bolted down in a couple of spots. Yes, you have to pull the intake to replace it, as well as the main coolant crossover - not difficult but make sure you have new gaskets/o-rings handy. I think I also had to move the AC compressor/bracket out of the way as well..

you do not have to remove the timing cover - i didn't, but it can be a little bit of a pain to get the end down in there and facing the right direction.. has a couple of odd bends...

there is a short hose that goes to the water pump at the bottom end - be aware you WILL get coolant out of there, even after draining the system.

I did this job on my 02 Forester a while back.. you can read about it here: https://www.ultimatesubaru.org/forum/topic/166852-coolant-leak-2002-forester-ej251-heater-hose-stub/

 

  • Author

I located second fuse box below glove box and another resistor pack below driver's side - still struggling to determine which resister to replace - see photos and please advise. 

 

Thanks, 

 

Milty

FuseBoxDriver.jpg

FuseboxPassenger.jpg

  • Author

I replaced hose throttle body to heater hose tubing - no leak at hose  - but a very slow drip is coming somewhere at T connection on heather tubing that travels over intake manifold to behind timing belt area. Can I use a stop leak to temporarily fix. Looks like a nightmare to replace tubing. 

 

Thanks, 

 

Bob 

  • Author

I found a relay fuse box under the glove box and more relays next to the fuse box under the dash on the driver's side - still not sure which relay is the "Main relay" See photos 

 

Thanks, 

Milty

FuseBoxDriver.jpg

FuseboxPassenger.jpg

  • Author

I reposted photos - then realized I already had replies. 

Thanks, 

Milty 

10 hours ago, milty60 said:

I replaced hose throttle body to heater hose tubing - no leak at hose  - but a very slow drip is coming somewhere at T connection on heather tubing that travels over intake manifold to behind timing belt area. Can I use a stop leak to temporarily fix. Looks like a nightmare to replace tubing. 

 

Thanks, 

 

Bob 

do not use stop leak products in your Subaru.

See my post above...

I thought I was starting to see double! 

Made me check where I’d scrolled to more than once! 

Cheers 

Bennie

  • Author

Pulled relay that was marked in picture - has a number on it 156?8-3818 - below it a -  V - I must of scratched the one number off trying to get the relay out it was tough to remove - its mounted flush in fusebox - couple of clips on both sides - I called Subaru parts - guy said that number is only a casting number - he tried to locate it on his diagrams - but could not find a "Main Relay" so I plan on pulling it over the weekend and taking it in -  he said he should be able to match it up then - can't believe how tough this is to identify - not feeling super confident he will identify it - I see two other relays in that fuse box that are identical to this one. 

________________________________________________________________________________________________

I'm going to pick up the cooling system conditioner and give it a try for temp fix to my leak problem. 

Thanks, 

Milty 

 

 

OK---this is weird.

The Service Manual says that relay is the Main Relay. I went to the following site and they call it Seat Heater Relay. It has the same picture that I posted?????

If your relay looks like the first one in both of the following links, it should be right because the pin layout is different on other relays.

Subaru Parts Warehouse in Branford Ct.

https://estore.subarupartswarehouse.com/a/Subaru_2009_Forester-25L-4AT-X-Limited/_52016_6023761/ELECTRICAL-PARTS-BODY-RELAY/S12-835-02.html

https://www.subarupartsforyou.com/search?search_str=relay

On 11/4/2019 at 9:53 AM, milty60 said:

Pulled relay that was marked in picture - has a number on it 156?8-3818 - below it a -  V - I must of scratched the one number off trying to get the relay out it was tough to remove - its mounted flush in fusebox - couple of clips on both sides - I called Subaru parts - guy said that number is only a casting number - he tried to locate it on his diagrams - but could not find a "Main Relay" so I plan on pulling it over the weekend and taking it in -  he said he should be able to match it up then - can't believe how tough this is to identify - not feeling super confident he will identify it - I see two other relays in that fuse box that are identical to this one. 

________________________________________________________________________________________________

I'm going to pick up the cooling system conditioner and give it a try for temp fix to my leak problem. 

Thanks, 

Milty 

 

 

the main relay is located just above/behind the fuse box on my 97 OBS. it should be red  i think

 

forgot this post was aabout an 09 fozzy

Edited by Hellzbellz1234

  • Author

Showed Subaru parts guy multiple wiring diagrams and pictures of fuse box – finally got correct relay – swapped it out – cleared codes but codes came back a few hours later – haven’t checked with odbc tool but assume same codes – will check this weekend. I don’t detect any issues with the car at this time – idle is steady – sits around 650 – no stalls – hesitation – power loss. Trying to decide my next steps for those codes?

Thanks,

Milty

Next step is obviously to read the codes. Record the codes, then systematically check/clean (if appropriate) each sensor. 

What was the main relay part number in the end? 

Cheers 

Bennie

On 10/26/2019 at 1:43 PM, milty60 said:

Update - replaced the downstream oxy sensor last week - son bought an odbc tool - Oxy code is now gone but found 4 more codes - 2 current faults - P0204 powertrain injector circuit - cylinder 4, and P3100 powertrain, also 2 pending faults - P0104 powertrain mass or volume air flow circuit intermittent - P2000 Powertrain - NOx trap efficiency below threshold bank 1.

I would have done the relay first because the MAF sensor and fuel injectors do not work correctly without the proper voltage. One down.

Just the other day I had to replace the new MAF bought in August on our 97. One from the junk yard fixed it.

 

I did some research on your previous codes. Mass Air Flow sensor or No. 4 Injector or the wire to it, or maybe MAF and injector.

P0204
Cylinder 4 Injector Circuit Malfunction. This code means the ECM detects a problem in the injector or its wiring, or in the injector circuit for cylinder 4.

P3100
Ignition System Or Misfire 
Fuel Rail/System Pressure - Too High 
Cold Start Injector Malfunction 
may also be triggered by faults earlier down the line. For example, a dirty MAF sensor might be causing the car to overcompensate in its fuel-trim adjustments. As a result, oxygen sensors are likely to report fuel mixture problems.

P0104
This code means that there is an intermittent or erratic fault detected in the Mass Air Flow (MAF) sensor or circuit. The ECM detects that the actual MAF sensor frequency signal is not performing within the normal expected range of the calculated MAF value.

P2000
NOx Trap Efficiency Below Threshold (Bank1)
This code usually indicates a faulty oxygen sensor(s). However, in some instances it can also be used for a faulty catalytic converter as well, since the O2 sensors are located on the exhaust system along with the cat. converter(s). You should check your O2 sensors before replacing the catalytic converter.

  • 2 weeks later...
  • Author

Cleared codes - 1 code came back P0104 - MAF circuit - I'm going to purchase the MAF cleaner and also reseat the electrical connector. Then, clear codes again see if it comes back. Any advice? 

Thanks, 

Milty 

MAF cleaner works as long as dirt or a bug is the problem. It worked on my 93 Ranger 4.0.

I did my Ranger on a Monday morning and would you believe it, during that same week at work, 5 guys asked me about the same low power problem. The cleaner fixed 4 of them. We got to sell 4 cans of cleaner and 1 MAF sensor.

I have not had as much good luck with cleaning it on our Subaru though. Sometimes the engine works a little better, but I usually have to replace them.

Get two from a yard and put one in a zip lock bag for later if needed, or an expensive new one with a good Warranty.

  • Author

Cleaned MAF sensor and connector - cleared code p0104 - it's back - I don't detect any drivability issues but need advice on resolving check engine P0104 code.

 

Thanks, 

Milty 

Load Pro is a great tool to ensure the voltage in the circuit is correct.  If the circuit is not loaded the meter will lie to you.

Check out Load Pro on You Tube.

  • 2 months later...
  • Author

I replaced the Relay a while back - idle is stepped up a bit. I still  have codes to investigate although the car does not seem to show any ill effect due to codes - at some point I will get hit with an emissions check from DMV and will have to get that light off and/or issues fixed.

I still have these codes: 

2 current faults - P0204 powertrain injector circuit - cylinder 4, and P3100 powertrain, also 2 pending faults - P0104 powertrain mass or volume air flow circuit intermittent - P2000 Powertrain - NOx trap efficiency below threshold bank 1.

I cleaned the MAF with designate cleaner - still getting code. Any thoughts on codes? I wonder if I have a short somewhere causing one or all of those codes? 

Thanks, 

Milty

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