Nightmare P2088 - Any advice please!

[NickCawks]

Hello all, long time since I had cause to post on here. However, as I sit here writing this I do so in utter dismay and reeking of failure.

 

I recently drove my legacy across the country (about 2k miles) the trip there was completely fine. The return trip was good until the last 500 miles or so. At this point, my car began to throw a P2088.

 

Now the car was driving and idling completely normally. So my first reaction was to clear the code and get myself out of limp mode. I had been driving for nearly 12 hours that day and I was not excited about my CC being unavailable. but the code would come back within 10 seconds of clearing it.

 

Less than 10k miles ago I threw a different code (can't remember it at the moment) that indicated my VVT solenoid was failing, So I went ahead and replaced both solenoids. Now that I am getting this code specifically referring to the camshaft position sensor, I go ahead and spent the last two days on a wonderful adventure of shoving my hands in small spaces to get those both replaced. The job went over fairly well and only caused me to cuss a couple of times.

 

Now I have put everything back together and turned the car back on. I was letting it idle in my driveway so the damn ECU can learn the correct idle speed. Just about the time my car reached operating temperature the code popped on again.

 

I'm at my wit's ends with this problem. I totally DONT care about this issue because the car is driving fine, BUT I don't want to be permanently in limp mode.

 

My buddy says it has to be my VVT solenoid(s), but I can't understand how a part that previously lasted 200k on my car has gone bad within 10k if being replaced.

 

I am not exactly sure what my next step needs to be and was ready to get some advice from others because clearly, I'm trying to shove a square peg in a round hole.

 

Car Info:

-2007 Legacy GT Limited

-215k - Well-loved and maintained regularly

-Turbo was replaced when I bought the car about 70k ago with an F-Diesel clone (not my choice, but hasn't seemed to be an issue)

-Tuned on Cobb OTS map

-Grimmspeed air intake

-Grimmspeed boost control solenoid

-Catless eBay downpipe

-Catless Noname 3" exhaust

-Otherwise, the car is completely stock

 

Any and all advice is appreciated, I truly will drive to someone and kiss their boot if they can help me solve this issue.

Edited February 2, 2021 by NickCawks

[B-BGTLimited]

This page has a lot of good information about this code... It sounds like not only could it be a bad actuator but it could also be an issue with the wiring returning the signal to the ECU.

 

https://www.google.com/amp/s/www.troublecodes.net/p2codes/p2088/%3famp

 

Sent from my Pixel 4a using Tapatalk

[Pleides]

Is the battery OK? What about the alternator?

[NickCawks]

Thank you guys for the quick responses.

 

I have actually read through that page several times already. I continuity tested the connectors going to the camshaft position sensors, but have not done the ones going to the solenoid. I will do that in a bit here and report back.

 

the battery is old, I've been meaning to replace it but haven't gotten around to it. And I had read that this code occasionally is caused by low voltage to the system. That said While I was doing this job it was on my charger/tender for two days. and before putting it back in I multimeterd it at 13.4 volts.

 

The alternator seems to be working just fine, I have had no issues that lead me to believe it's going out, therefore haven't actually tested it in any way.

 

Sounds like I need to:

-Continuity check the AVCS solenoid connectors

-Load test the battery and possibly replace it

-Load test the alternator - and cross my fingers I don't have to replace it. money is tight right now :/

 

 

On top of that

-Is there a way to multimeter the solenoids themselves for function?

-I do have a cobb, but by no means have any deep knowledge of tuning. However, I did read someone saying there is a way to check the degree that it's actuating. This seems like a really good way to check the functionality of the solenoids themselves. Can someone direct me on how to view this in my cobb and I'd also need to know what degree they should be getting to when functioning 100%

[m sprank]

Thank you guys for the quick responses.

 

I have actually read through that page several times already. I continuity tested the connectors going to the camshaft position sensors, but have not done the ones going to the solenoid. I will do that in a bit here and report back.

 

the battery is old, I've been meaning to replace it but haven't gotten around to it. And I had read that this code occasionally is caused by low voltage to the system. That said While I was doing this job it was on my charger/tender for two days. and before putting it back in I multimeterd it at 13.4 volts.

 

The alternator seems to be working just fine, I have had no issues that lead me to believe it's going out, therefore haven't actually tested it in any way.

 

Sounds like I need to:

-Continuity check the AVCS solenoid connectors

-Load test the battery and possibly replace it

-Load test the alternator - and cross my fingers I don't have to replace it. money is tight right now :/

 

 

On top of that

-Is there a way to multimeter the solenoids themselves for function?

-I do have a cobb, but by no means have any deep knowledge of tuning. However, I did read someone saying there is a way to check the degree that it's actuating. This seems like a really good way to check the functionality of the solenoids themselves. Can someone direct me on how to view this in my cobb and I'd also need to know what degree they should be getting to when functioning 100%

 

 

Definitely complete the electrical checks first. How many miles are on the engine? It could be a failing AVCS pulley as well. They can build up a lot of "gunk" and metal debris which can cause them to fail.

[NickCawks]

Alright just ran to Advance and got my battery and alternator load tested. The guy said they were both golden. 12.6 on the battery and 14.3 on the alternator.

 

I also just went out and continuity checked both connectors going to the solenoids - both came back good.

 

the car has around 215k on it. I'm going to immediately look more into this AVCS pulley situation. Is this separate from the cam gear? I've done a lot of work on my Subarus but have never had the sarcastic pleasure of doing anything with pulleys or timing. I had a buddy that ran a shop who would normally deal with things like this on a friend discount for me, but the pandemic killed the shop.

Edited February 3, 2021 by NickCawks

[Max Capacity]

http://people.csail.mit.edu/ilh/vacation/

 

the service manual may be some help.

 

Sorry your friends shop has gone away.

 

The DIY forum, "walk through's" below may have some info on the AVCS, they can be a PITA to remove as the 10mm hex bolt can be a nightmare.

[B-BGTLimited]

AVCS pulleys can get nasty inside... granted this was from a motor that lost a rod and was run way too long that way. The AVCS portion is the center of the actual timing gear on the cam, so yes they are a pain in the ass to remove/service if needed.

 

 

 

[NickCawks]

I did a good bit of research on the AVCS pulley yesterday. Cleaning the AVCS pulley seems like no problem, but it does seem like it would be difficult to get it off. Especially with the motor still in the car.

 

However, I am starting to lean towards this being quite likely as the culprit to my issues. I went to move the car out of my garage this morning and while it was warming up I noticed a sound I have never heard before.

 

Sounds like a revolutionary squeal, my mind immediately likens it to a failing bearing on one of the pulleys.

 

the video doesnt really do it justice. Its much more noticeable over my exhaust in person.

 

It certainly makes me nervous and I am concerned that im in for a decent smack to my bank account

[B-BGTLimited]

These pulleys don't have any bearings on them, they are bolted directly to the cams which are supported by the cam carriers in the heads. The adjustable part only moves a little bit when it's being commanded. But if that's the case I feel like you would have more cam position codes vs an actuator circuit low code. That's why I feel like it could definitely be wiring from the AVCS solenoid to the ECU causing the issue, or the connectors are corroded causing poor connection.

[NickCawks]

Thanks for the quick reply.

 

I wasn't necessarily saying this noise is the cam gear, more meaning that it's clearly time to get in and replace my timing idlers and pulleys, and doing the AVCS pulley cleaning isn't much of a leap of effort on top of all that. It would really chap my ass to get this problem fixed only to jump teeth and bend valves down the road. The car was bought used and I highly doubt the timing stuff has ever been done. If anything this problem has forced me to pay attention to other potential problems that are on the rise. I do love this car and I want it to keep going as long as possible.

 

All that said, I did check the continuity on the connectors to the AVCS actuators and they came back good as well as identical, and as my code only indicated one bank that makes me feel that both sides are in spec.

 

I still need to double-check the degree the actuators are opening during operation to confirm I'm just not in need of replacing one of them to move on and I suppose it would be a good idea to go blast those connectors out with electrical cleaner just to make sure. I will also come clean and say I used some cheap $45 actuators to replace the OEM ones when I did this about 10k miles ago, so I still haven't checked that off the list as being to cause of my code.

 

with the development of the new sound clearly coming from an idler or a pulley I am just cramming some research on the entire prospect and trying to build my confidence towards doing a job I would normally pawn off to a shop, but just can't afford to do so at the moment.

 

To-do:

-Check the degree of actuation on AVCS solenoids (still trying to figure out how to do this on my cobb)

-Blast AVCS Solenoid connectors with electrical cleaner

-Re-confirm that the issue is not a wiring issue (AVCS solenoid connectors and deeper)

 

On my new to-do list:

-Locate a good (Japanese sourced parts) timing kit

 

If anyone has any suggestions on a brand to look into that would be greatly appreciated.

 

Again thank you guys for all the info and your patients with my ignorance. I will keep you posted on my findings

Edited February 4, 2021 by NickCawks

[B-BGTLimited]

At 215k I would hope the timing belt/pulleys have been replaced at least once in it's lifetime... Honestly I wouldn't expect an original timing component kit to last that long... mileage or years.

 

Aisin kit's are apparently the go to now over the Gates stuff. I just bought mine (TKF004) for my 06 build from RockAuto for $266 after discount and tax/shipping.

 

As far as the noise too, pull your alternator belt, and your AC belt and see if the noise is still there. That will help narrow it down some, since that could be PS pump whine.

 

How did you check for continuity? I'd also be checking for Ohm's on the full wire length, or at least to the engine harness bulkhead under the hood.

Edited February 4, 2021 by B-BGTLimited

[NickCawks]

I just set my multimeter to the continuity setting, grounded the multimeter on the frame, and probed the connector with the positive lead of the multimeter. This resulted in the multimeter making a sound and giving me a reading. I cant remember the number exactly, but I did note that it was the same between the two connectors. I had found a video on youtube where someone was doing this, but of course, cannot find it again today.

 

Electrical is not my strong suit, how would I go about checking the ohms?

[m sprank]

Physically check timing. With that many miles the engine could easily have skipped a tooth on one of the gears.

 

 

The AVCS gears are not technically serviceable. Although one specific shop wrote the book on it as they figured out how. Most "mechanics" should just replace with new.

[NickCawks]

I will definitely be checking it when I get the time here in the next couple of days. the thought of there being an issue with timing is now looming over my shoulder.

 

I have no idea how much they cost, but I'm assuming I don't want to spend the money on a new AVCS pulley. I watched

of a guy disassembling and cleaning. Seemed pretty straight forward and that part doesn't concern me at all, it's getting it out that concerns me.

[B-BGTLimited]

As far as doing a wiring test you should determine what pin on the AVCS plug correlates to what pin on the engine harness bulkhead, you'd put the negative at one end and the positive lead at the other and it will tell you the continuity of the wire as a whole. You can also set the meter for ohms and see if it will give a reading. You may have to experiment with the ohm scale to get a good reading though.

 

I'll take a run out to the garage in the morning and figure out what pins my AVCS plugs go to on the bulkhead and try to get you a photo of a bench test.

 

I found AVCS cover seals on ebay from Russia.... Took a while to get them but they are very easy to tear down and clean. You just reuse all of the plastic seals and springs when reassembling... And obviously if one of those is bad you'd have to replace the whole thing at that point since I wasn't able to find those pieces.

 

Sent from my Pixel 4a using Tapatalk

[B-BGTLimited]

Here is how you should be checking the harness for continuity.

 

I de-pinned the connector to get better access to the wires. Traced them back to the bulkhead and then you put a probe at each end and ensure your OHM reading and continuity is consistent between the two wires.

[NickCawks]

Wow, that is extremely helpful, I appreciate you taking the time to do that.

 

So I've had a slight development today. My brain decided to actually work for me this morning and I thought why don't I just swap the AVCS solenoids over to see if the code moves, and sure enough it did.

 

When I started the car it is now throwing a p2092 instead of the p2088. These codes are identical aside from indicating either bank 1 or 2.

 

This makes me fairly certain that the solenoid itself has failed and not the wiring (thank goodness).

 

New solenoid will be here on tuesday, ill keep you guys posted on my results

Edited February 7, 2021 by NickCawks

[Pleides]

Lucky you that yours gave you a code. Have you lost a turbo recently? If you change those things out, I'd recommend changing your oil very, very early for the next few oil changes. Like every 500 miles with synthetic early. It takes a bit of work to clog those things up and it's typically advised to replaced those after turbo failure.

 

I replaced both of mine on my old engine and the car ran perfectly for about a week. After that, they got clogged up with whatever gunk was in the engine. I did an engine oil flush which solved the problem until the gunk in my engine got stuck in the oil pickup tube.... you can guess how that went for me.

[NickCawks]

Yikes that sounds rough.

 

The car lost its turbo around 140k (before I owned) it. The shop I bought it from replaced the turbo and gave it a clean bill of health.

 

I've put roughly 80k on it since then and have never noticed anything in the oil. I do my oil changes at 3k religiously with Castrol edge and always use a can of BG MOA.

 

When this one started acting up I had done the oil change right before getting on the road for a 2000 mile return trip home. Ive done this trip quite a few times and always change it before leaving at both ends.

 

I'm really thinking I've got to chalk this one up to buying cheap Chinese replacement solenoids that I put in around 10k miles ago.

[Pleides]

Yikes that sounds rough.

 

 

I'm really thinking I've got to chalk this one up to buying cheap Chinese replacement solenoids that I put in around 10k miles ago.

 

Ah, that'll do it. Don't use aftermarket sensors on these cars. Denso is as high-quality an OEM for those sorts of things as they come. Toyota uses them for everything. Same with Subaru. Hopefully just some new OEM ones will solve your issue.

[NickCawks]

Got the new solenoid in this morning and took her out for a test drive. Everything seems to be on the up and up and working correctly now.

 

Next up is looking into the timing and figuring out what the rattle coming from my suspension that happens between shifts is.

 

I want to thank you guys again for all the help and advice. It's very reassuring to know that there are people who will take the time to give a hand to those in need!

[Pleides]

If your car has been tuned on aftermarket AVCS solenoids then I'd definitely recommend a retune

 

Could be your driveshaft starting to go out, this noise between shifts. They're old now. I need to replace mine as my carrier bearing moves a little too much for my liking now.

[NickCawks]

I am just using an OTS tune from cobb at the moment. Been planning to get an e-tune, but haven't gotten around to it and just cant afford a pro tune.

 

Ill have to check that out. I haven't checked that area. It sounds like the rattle is coming from the front drivers side, but all the suspension components there are fairly new and in good shape

Edited February 11, 2021 by NickCawks