P0170 intermittent idle bounce

[thinkjon]

hey all,

 

2006 v70R 105000 miles bought for way to much money at 32000miles 4..5 years ago

money pit... yeah I almost spent my $5000 in repairs when I was forced to have the clutch done when slave went and did rear main seal at time and then had to replace ignition lock and DIY parts for PCV.

I'm not a great mechanic mainly due to lack of experience but I have done clutch twice on a jetta and I have done 3 out of 4 bearings on the R (and i hear maybe the last one starting to go and the PVC on R and few other little things on my jetta

 

I've been searching around a little so I apologize if the topic has been covered....  a couple thousand miles after doing the PCV replacement (yep broken upper) and I replaced plugs coil packs, all done since I thought it would resolve poor gas mileage and major oil consumption (qt in under 500miles).  Well i can say WOW to the MPG.. I took  a couple big road trips and got 27.4 MPG at 70-79 MPH, and looked like no oil consumption after 500 miles or driving.  started to use it to commute with traffic and 300 miles noticed oil consumption again.  well now I went about 730 miles and used a qt of oil.  reset Odometer and about 1/2 qt in 500.  So I think this issue is completely unrelated to my check engine light....I also replaced the the throttle inlet tube with IPD one since i noticed it was cracking  I cleaned the throttle body ( little dirty) and exhaust manifold as best I could. 

 

 

the PROBLEM :

I noticed while car fully warmed up at a light a couple times the idle bounced up like as if i touched the gas pedal.  I don't think so but i'm not exactly sure if the car would have stalled if it didn't bounce.  this now happens every once and awhile  and I get a code of  P0170.

 

I looked under the hood and noticed a couple of the small hoses (like the thin one attached to manifold on right side pointing towards rear of car) had popped off just a little.  I pushed them back on and made sure the clamps were tight although one that came off half way is clampless.  

 

I'm not sure if any my issues are related. although I have put at least 1500 miles on car since i did PVC with no issues. No clue why the couple hoses would start to pop off but only looked under hood recently with cel to see if i had a crack in a vacuum line.

 

my thoughts... bad temp sesor? bad O2 sensor(s)?  something I messed up with or touched when doing my own work on car that took time to mess up. I'm always paranoid i'm going to make my repair work cost me more cause ill screw up and need dealer to fix.  

 

I'm only mentioning oil consumption in this post to give background info.  I really do want to discuss the oil issue but i think i'll look it up first before i start a new thread. Figured i would get yelled at if I post 2 issues on one thread

 

thanks all!

Jon

[Ihatespeedbumps]

Your oil consumption issue is not going to be related to your CEL or rough idle. It sounds as though you have a vacuum leak somewhere. Do you have the ability to smoke test the system to check for leaks?

 

Your oil consumption is likely due to a failing turbo.

[thinkjon]

Thanks for the quick post... I do not know how to do a smoke test. Although I am hugly concerned about oil issue I would like to deal with the cel. So I guess u feel O2 sensor csnt cause this. Drove it all day today and it didn't bounce once. Kinda hard to figure out when it is not consistant I'll you tube smoke test. Thanks.

[Ihatespeedbumps]

Not saying it couldn't be a sensor, but your symptom is a characteristic of a vacuum leak. If you found a hose that was off and you re-connected and the symptom is gone you very well may have resolved your issue. Probably not a bad idea to clear the code and drive for a few days to see what happens.

[SharkGTS]

>Air leakage to induction system (air is getting into the engine, bypassing the MAF = revs up)
>Blocked crankcase ventilation or PCV nipple
>Faulty MAF

 

The induction system needs a going over. You can test the vacuum systems by well testing each line off the manifold for leaks. I have not looked at the Idle control valve on the R  but that also may be an issue 

 

However oil consumption could be the result of high crankcase pressures. If the crankcase venting is blocked somehow, then pressure builds, causes oil vapors to blow by the rings and I imagine this would also kill efficiency (MPG) because the pistons are working against crankcase pressure.

 

It could well be the source of the idle malfunction if excess oil if getting to parts where it shouldn't be (ie MAF!) 

 

Might want to start with a compression test too, just to rule out any internal engine mechanical.  

PS: I have a spare MAF I will be selling when my car sells, hopefully in a few weeks!

Put a balloon on the dipstick...

[SharkGTS]

Might want to read through this - not sure if our R's use the same "membrane" but sure sounds like a similar issue:

http://v70r.com/forums/topic/38428-2007-32l-with-codes-p0171-and-p0174-help/?hl=%2Boil+%2Btrap

[thinkjon]

Thanks ... I'll look into where air could be leaking in and bypassing MAF... Sounds also like I should be checking every line

I wish the code could could be more specific with what is wrong. I did neglect to say that I replaced the entire PCV system and recently to double check that I thought I messed up I did the glove test. It sucks all the time. Maybe I can set up some kinda glove test with oil cap on and make sure that's not leaking air

Most recently I noticed that although my exhaust always poped... It seems to be doing it more or im just nuts looking for issues.

I guess I'm running 2 issues on same thread and hope not to bother people with it. But I know I need to look for major oil leaks again( haven't found in past (pre PCV used a qt in 300miles so stopped driving it till I did PCV) I was told that most of the oil issues ( consumed oil from day one just tolerable amounts) would go away if when I do the timing belt to have all seals done. I assume valve seals as well as cam seals. As mentioned before about a year ago the rear main was done as precaution when I paid for clutch to get done.

My neighbor has a compression test kit so I'll learn to use that but really wanted to address this cel first.

Also to reiterate .. I didn't find any lines poped off but curious what could make a couple of them come off half way. I did reset the cel and it was good for a day and then the idle Bounce happened and light came back on.

[SharkGTS]

Turbo engines have a more complex vacuum system because they run under boost and therefore a vacuum pump is used. I believe all your symptoms could be inter-related, so it would be a good idea to write them down in a short list. I also work from diagrams - Vacuum system and PCV for example.

 

The only way hoses would blow off, is if there is pressure present instead of vacuum. The only way I could see this occuring is if the boosted side of the intake feeds back into the vacuum system - I dunno I would have to trace it out.

 

Diaphragms interface between vacuum and other systems - for example atmosphere, or turbocharging (CBV). In my case, where my whole car BURNT DOWN, the CBV diaphragm was split, causing the turbo to draw or PUMP air from the engine vacuum system.   This caused a failure in the brake booster > master cylinder seals that sucked all brake fluid into the hot turbo and ignited an unstoppable fire. Amazing but true. Most people aren't equipped to understand that relationship or causal effect. VW engineers put in a check valve, Volvo engineers didn't not and it could well have cost me my life.  

[thinkjon]

SharkGTS

 

thanks again for keeping the thread going.. with a full time job and a 3 and 5 year old at home it is difficult to work on my car.

I have to check my settings, but i use to get an email when there were replies on my threads.  Guess I need to revisit me settings.

 

Anyway,  crazy story about your turbo.   I tried to do a glove test with oil cap on.  I kinda need a second person to help me to make sure glove is forming a good seal, but it doesn't seem like air is getting in via the oil cap, but i would revisit the possibility.  I also tried a throttle body cleaner spray (but was almost empty and need to try again maybe a true carb cleaner next time) to spay an listen for idle pick up to see if i have a air leak in a vacuum line.  sad that i didn't even have enough time to go and get a new bottle , so another inconclusive test. revisit.

 

I recently check again and all lines seem to have stayed in place.  So i tried to recall exactly what happened the day I did the PCV system and although I know i put all hoses on, I do remember that i tried to start the car like an idiot after the wife even said, do you know you still have extra parts on the garage floor.... i thought it just the old crap, nope it was the charge pipe.  No wonder the car wouldn't start.  I wonder if that could have caused some weird thing to happen and i never noticed the 2 lines popping 1/2 way off and I had just driven the car that way problem free for over 1000 miles and only looked when this new issue happened.  any clue if that could have caused vacuum lines to come part off?I would love a detailed picture that actually shows all the lines and everything.

 

so ~500 miles and I needed to add 3/4 of a qt of oil (thank goodness for the low oil light vs idiot light).

 

today I had a min to look under the car, how could I use up oil so quickly and not have an obvious leak?  well everything looked fairly dry, except for the angle gear ( of course) looks like a glaze of fluid on the bottom of it.  as if i don't have enough going on with this car, the seals on the angle gear are going???  there actually looked like a bolt on it that allows one to check the fluid and add.. could I be right on this?  I really don't think it was oil.  

the entire area of the turbo looked super dry, could there be an internal leak in that and it pushing oil into the entire system and not burn enough for me to leave clouds of smoke all the time? New PCV system  just dealing with it till it gets clogged or breaks

 

the only accomplishment I had was adding oil and calling volvo for an estimate of timing belt, cam and valve seals, so when i throw in the shop rag I know the base price of what i'll be paying.  Maybe I toss a sign in or trade it in a get a XC, legacy or all road .. oh wait I really can't afford a new family car.  

 

peace

[1clean00]

I'd start with cleaning the undercarriage.  Then when you can actually get the vehicle on some jack stands or ramps,  have a better look for the source.  Could be as simple as an oil dipstick o-ring, or turbo drain gasket and o-ring.  I had an oil change place once try to convince me that my rear main was leaking,  when it was in fact the turbo oil drain gasket and o-ring. 

 

A different shop tried to convince me that my front crank seal was going on my T5,  when it was simply oil cooler o-rings. 

 

So now,  i do all my own work.  It's worth it on these cars to be able to wrench on them yourself. 

[SharkGTS]

I did some searching still haven't found hose routing for the R engine. Just to keep things simple, the only way engine idle can flare is if there is

 

a) air ingress on the vacuum system. The vacuum system is a closed system. When valves open or solenoids fire, they move actuators. If there is a split diaphragm, disconnected, split or open ended hose, then air shoots in. 

idle control - there is a valve that uses engine rpm to throttle air into the engine to control idle at rock steady values. For example it the A/C button the control system adds air to prevent the engine from dogging out.  If this valve is NFG you can get idle control issues. 

 

Pressure at the oil cap, crankcase pressure has to do with the PCV system (oil vapor recovery & combustion), NOTHING to do with air intake, unless there is a faulty part or something is screwed up. Based on the OP's posts I really think this should be turned over to a good wrench, and forget the fussing about. 

 

Intake cleaning doesn't mean much either in terms of performance unless something has caused the intake to gunk up with oil. The MAF is a hot wire sensor and doesn't like contamination.

 

So with some basic knowledge and diagrams, google you can usually figure what's going on. Example my car was cutting out on the highway, no rhyme nor reason for it. Google = fuel rail pressure sensor. Went into the shop told them that's what it was. "Oh we will diagnose etc etc." I said  put the part on order now in any case. 3 hours later they changed it out, with just one fault code the tech was suspicious that was it. Of course it was it. Sound and feel of the engine are big things for me. There are curve balls, but there is always a reason. Just have do the old "process of elimination" and if that involves plugging lines or pulling plugs, then so be it. 

[thinkjon]

thanks again for the advise... life has just been non stop and i'm not sure if I am going to be able to have the time to fix this on my own.  Before i know it december will be here and I need to take a huge trip with this car, and it almost always snows big time on us.  Man oh man this car with snows and MT is just the most outstanding thing to drive in snow.  I actually prefer it to the MT jeep i got.  so now pushing 105,000 I think I am going to tae it to volvo (who seems to be the only local shop that is willing to work on my car) and get them to fix it....

and while they have it, maybe i'll be super lazy and let them do that last rear bearing that I have not done (why i replaced 3 and not the 4th), cause of course now i have to listen to this car moan at 20 MPH in traffic and have the CEL blaring me in the face as I come to a stop and watch the idle kick it up a a fe hundred RPM's.  I just got some ridiculous estimate for the work my jetta needs, so i think i'll put my time into that car, this way if I mess up its no big deal.

 

sorry to give no new update, and just venting...

I think if I hunt around, i may find the p0170 reason, but I'm really not getting a good feeling about the major oil issues I am having.  I may have to tell my brother to hold off on selling a few parts of his s60R that i may need.....ie, engine, angle gear, turbo...

 

on another lighter note, Does anyone know if I should hold on replacing the water pump? I have read a couple times to not replace it unless it is leaking when doing the first timing belt?  I have also been told that the replacement water pump is not the same one that came with the R's and it will not function as well.  apparently there is now only one part number and there use to be 2?  No clue to the validity of that

 

hope the thread jumping is acceptable 

thanks all

jon

[1clean00]

Idle bounce in these cars could be related to the ETM, as the ETM serves as the idle control valve.  There is no separate idle control valve like on the pre 99 cars. 

 

I would start there with a thorough cleaning, and clean the MAF, make certain the intercooler to ETM pipe isn't cracked and is seated fully and clamps are torqued down tight.

 

P0170 is a fuel trim code.  So you code just have a leak like others mentioned,  near the ETM or close to the throttle, which is why the idle fluctuates as the motor is leaning out. 

[thinkjon]

thanks 1clean..

 

i guess i should make sure the brand new IC to TB IPD silicone pipe didn't come loose over the last couple thousand miles... maybe it is that simple.. i don't wanna take the intake off again to make sure so i guess I'll go from the air box side and hope i can feel my way around..  That intake is a real PIA cause of the stupid banjo (sp?) bolt from the PCV&coolant line running to driver side engine.  I know i had a hard time getting th pipe to seat well and i used 2 clamps to make sure it stayed on... 

 

if i use carb cleaner in that area, the idle should shoot up consistently right?  any recommendations what carb cleaner of starter fluid i can use.  I heard that some Throttle bodies have a coating on them that you can not use any carb cleaner that will strip the coating off... need i be concerned?

 

I'm new... so i dont know what ETM means?  

i would like to fix this issue before i drop car off for oil issue...  and determination of why the angle gear seems wet with fluid... the turbo looked real dry as did just about everywhere else... the plan is...

timing belt, cam seals and valve seals and have them look for what else could cause the massive oil consumption... 

 

any and all advise is welcomed...

i hope this helps out others in some way

 

thanks again... and I am really trying to make time to work on this but not an easy task with job and family. so thanks....

 

Jon

[thinkjon]

ok had a few min to research... ETM.  got it... ..so i thought i cleaned it well.... but i see videos of people using a wire brush and opening up the center disc and cleaning the edges.  I think i was a bit delicate with my cleaning method.  Also maybe something isn not right with the sensor.  so at least now i have a few idea that you all helped facilitate.  it looks like this idle bounce happens to a good amount of volvo owners.. Mine not nearly as wacky or often as other people.

 

just my update of... at least I'm trying to look up some stuff.  the clock is ticking and I may need to toss in the red rag.  I also don't know if my massive oil consumption is gunking up the ETM right?  i guess i could take a look at the pipe from intercooler to ETM and only look at the intercooler side since it is a much easier access and look for some oil?

 

thanks for reading

Jon