2002 xc70 motor blown

[Jpm53]

Have been off the forum for awhile. Last time I was here, I was in California having throttle control problems. Since then, I replaced the MAF with no help, got it home and had no problem for about three months then started having loss of throttle control intermittently again. Then recently got a CEL saying bad throttle pedal/throttle position sensor so replaced the throttle pedal. Had one more instance of the loss of throttle, then no more problems for about a month. Just an FYI, the throttle pedal replacement seemed to help alleviate a 3/4 shift flare I was having and seemed to help the shifting overall.

Now, my wife and her mother left from here (Oregon) last week headed for California again for a funeral. Just north of Los Angeles, she experienced a loss of power and excessive blue smoke. Upon opening the hood, had a lot of oil on top of the engine. My first thought was a plugged PCV system which I had read was a common problem with these engines. Had it towed to a friends house and ordered a PCV kit and was going to drive down and fix it. Upon further inspection, he found 50 lbs. compression in number 3 cylinder. I have attached a picture he took with his boroscope.

Anyone have any idea what may have caused this?

8166

[albertj]

Pre-ignition and/or detonation (as opposed to normal combustion), I am thinking detonation-induced pre-ignition.

For background and details see http://www.contactmagazine.com/Issue54/EngineBasics.html, a very good primer on the topic, about 12 pages long.

Albertj

[albertj]

For the rest of you: Detonation is uncontrolled explosion of the fuel/air mix in the combustion chamber. Carbon buildup among other things can lead to "hot spots" in the combustion chamber, in which fuel/air will explode without prompting of the timed spark.

The quickest and easiest way to cure detonation is to use a high-quality, higher-octane gasoline.

From time to time a combustion chamber cleaning could help. Some cleansers are OK, others are crap. Cleaning the fuel injectors is important as well, especially in an augmented-aspiration (turbocharged or supercharged) engine. There are 3 issues with pour-in fuel injector cleaners. One, effective injector cleaning requires chemicals than can't legally be sold in stores as fuel additives for cars and trucks. Stubborn injector deposits must be cleaned using more force than an engine’s fuel system can provide. Three, loosening the deposits as often as not just moves them "downstream" where other problems can be caused.

The quickest and easiest way to clean fuel injectors effectively is to remove them and have them cleaned.

Finally, watch out for scams: see http://www.popularmechanics.com/cars/how-to/a2015/4220245/.

I am not sure what I'll do on my Volvo in this regard. On a Buick I own - I bought it at 48,000 miles and now have 335,000 on it - I dump a bottle of Techron in each oil change or so (the tankful *before* the oil change); I only burn premium fuel; I have 2 sets of injectors, one in the car and the other I send for cleaning and when they get back I hold them for when I replace spark plugs (every 100,000 or so, using Iridium plugs). Oh and about the Buick: have not bothered the engine except for normal maintenance and to change valve cover gaskets; I do wash the engine each spring/fall to be able to better see leaks and other issues.

[kutcht1]

Bet that Buick has the 3.8L.
TomK

[albertj]

Bet that Buick has the 3.8L.
TomK

[non-Volvo content]

No need to bet, Tom. It's the 3800 Series II, blown (supercharged):
* 240 hp @ 5200 rpm
* 280 ftlb tq @ 3600 rpm
* 8.5:1 compression
* FWD through a 4T65E transmission also used in certain Volvos),
* balance shaft, crank driven oil pump, DIS, hydraulic roller camshaft, integral PCV, roller rocker arms, M90 Supercharger
* 36 lb/hr injectors

At 70 mph it's loping along at not quite 1900 RPM, 24-27 MPG at that speed depending on conditions.

You can hear it rev and run with a custom exhaust here: https://www.youtube.com/watch?v=AlhoW4BWgHs

Not long after I changed the exhaust to a nearly silent 2004 Park Avenue Ultra system, set up to hang on the Riv, from GM Wixom Performance Build Center. I sold the SS exhaust because it was fun each day for the first 25 miles but the drone was a bit much... to a vintage-Buick-gearhead who thought (and still thinks) the drone was the bomb-diggity.

[Volvo content]

@ Jpm53: what brands/grades of gasoline did you use?

Albertj

[v70+xc70]

Is that the piston or a valve? If latter looks like the cylinder head seat melted. Definitely toast. Replacement heads and engines must be around used.

[Jpm53]

It is the piston. I'm sure replacement motors are available, but after all the trouble I have had with this car, I'm done. Would cost me probably $500+ to drive down, rent a dolly and bring it home. Already have spent over $2,500 on this POS. Rebuilt the transmission, which was the only problem it had when I bought it for $800 so I expected that, had to replace the MAF, replaced the throttle pedal per CEL, replaced the window motor, replaced the window switch (neither of which fixed the intermittent drivers window issue) every time I adjusted the seat back it would blow the seat fuse, replaced the battery (also knew about that when I bought it), replaced both front struts and both front axles and replaced the front brake pads and rotors. Constantly had loss of throttle control (when throttle was depressed the engine remained at idle) and stalling issues. Probably more that I have forgotten about, but seems like I was spending at least $150 per month on something. So this issue with the piston melting is the last straw. Really loved the way the car looked, handled and rode, just couldn't keep it working.

Just bought a 2002 V70 2.4T that had a broken out quarter glass, transmission problems and a heater that only blows cold air for $300. Had replaced the linear solenoids when I rebuilt the trans in the XC which turned out to be a cracked C1/C2 clutch drum so put those solenoids in this V70 and the trans now shifts perfectly. Bought a replacement glass for $65 so now just need to get the heater working. Now that the XC is done, I might consider keeping this V70 but am afraid now, very afraid. Was the XC just a lemon or are they all this bad?

Sorry, I'm rambling now. At least I know that I need to run premium fuel in these turbo motors from now on. Ran mid-grade when I first got it then got cheap and started running regular, so maybe this motor issue is my own fault?

Thanks to everyone for your input.

[albertj]

@Jpm53: I would not say the motor issue was your *fault* but I would say you were involved. Cars for use on USA roads are supposed to be able to burn regular gasoline. You can do that on these engines and odds are they will last through the initial warranty period. Further longevity, however, is a different discussion. To get performance and longevity, even mid-grade is not enough. Will they run regular? Yes. Will they run it well over the long run? Probably not.

I am sorry about your loss inasmuch as you didn't link the action (burning regular) and the possible consequences (engine damage).

[albertj]

From Edmunds.com:

"Compared to premium gasoline, lower-octane fuels don't allow the engine to run as much ignition advance during situations calling for rapid acceleration. More ignition advance allows the engine to make more power, and accelerate more quickly, during these conditions. Since the engine doesn't make quite as much power with lower-octane fuels, this translates into slower acceleration in cars for which premium fuel is recommended. The performance loss is especially noticeable in turbocharged gasoline engines, which have become increasingly popular in recent years.

"The performance loss, however, is something you will only notice if you have a heavy foot and accelerate rapidly from a dead stop or while changing lanes at highway speeds. But if you accelerate moderately, the loss of power is barely noticeable, regardless of whether you use premium or regular-grade fuel."

With my 2007 XC70 the difference between running premium and running regular is palpable. The PO had been running premium and switched to regular later. When we got the car it had a tank full of regular. We immediately switched to Premium, we had noticed over the years that our turbocharged cars ran better on it. And our non-turbo cars (a Mercury, a Nissan, a Chrysler and a Buick SUV) usually ran worse on it. On the XC70, we saw no difference until the third tankful of Premium... then Holy Smoke. Let's just say I think the engine finally read the memo.

Further from Edmunds.com:

"It's a different story for a car whose engine requires premium fuel. The car will still run on regular fuel in a pinch, but you shouldn't make a habit out of it. The fuel's lower octane can result in elevated exhaust-gas temperatures and possible knocking, both of which can adversely affect the engine's health in the long run. Running regular-grade fuel in a car that requires premium might sound like a good way to shave a car's running costs, but the short-term savings won't come close to offsetting the cost of repairs to a damaged engine."

The Volvo 5 cyl. is on Edmunds' "premium recommended" list, not the "premium required" list like the turbo version of the Subaru boxer engines are.

Mid-grade fuels are a marketing artifact, by and large... I've read that the minimum standard for a mid-grade is ~35% premium and the rest regular gas in a tank truck, allowed to "splash blend" en route to the delivery point (the gas station you buy it from). Some cars no kidding run better on a midgrade fuel. Often the owners manual will mention something about it. Basically, if you are running a normally aspirated higher-compression engine it should run better on midgrade fuel. Thinking about people I've talked to about whatever, some will switch to mid-grade (especially in the summer) because they notice their engines knocking. A rule of thumb might be that the higher your engine's effective compression is, he more benefit you'll get from burning midgrade or premium fuel, depending on various things. My rule of thumb is if I'm driving a car with a supercharger or a turbo, I'm burning premium if only to avoid the long-run costs of not doing so.

I mean, a lot of this is marketing. The terms "premium" and "regular" disambiguate the standard fuel grades but don't necessarily mean "premium" is better fuel. Although it is promoted as such. The physics, however, is that lower octane fuel burns quicker relative to higher octane fuel; higher octane fuel burns longer relative to lower octane fuel. We are talking milliseconds of difference, though.

Part of this is Not marketing: I have read that as a practical matter, by the time a person has driven a car 15-20 thousand miles, there will likely be enough carbon buildup in the combustion chamber that switching to midgrade will yield improvement (less knocking, better mileage) in excess of the difference in price by allowing the engines that have management systems that will compensate spark advance timing to run more agreeably with midgrade than with regular. Why? Premium fuel won't likely detonate on compression, but regular is prone/likely to do so in a higher compression engine situation.

So I suppose the question is, do you notice pinging or knocking on acceleration - like, when you merge onto a highway or pass another car on a secondary highway (have to move quickly there, really quickly...). One way to get midgrade cheaply into a car that burns regular but knocks: do fill-ups (3/4 tank or more) with regular and top-offs (1/4 tank or less) with premium, provided you can conveniently keep track of when to fuel with which so that you are between 1/4 and 1/2 premium gas in the tank. Or just use midgrade for a while (3 tanks) and see if the knocking goes away (most likely it will). With our Buick SUV (had the 3.6L VVT engine) it ran fine on regular, no knocking problems or what-have-you. We tried premium for a while just to see what would happen, for 4 tankfuls. It ran worse - worse average mileage and my butt-dyno registered no benefit. No more premium for that car, I think it would have run on orange kool-aid and alcohol in the gas tank had we dared to do so.

Be careful out there.

Albertj

[JRL]

I've been running these engines now fro nearly 20 years! (1997)
Either a 2.4T or a 2.5T and if it has a stock factory tune... 89 octane (mid grade) has always been just fine with never a problem
I would NEVER run 87 in a turbocharged motor, never, ever!
Once in a while I give it a treat with premium.
Lately I have been running them tunes (either Polestar, Hilton, IPD, etc) so now the minimum I run is 91 with every other or every third fill up with 93!

[Jpm53]

Thanks to everyone for the great info and friendly admonitions. I will absolutely run premium in my turbo engines from now on. The fuel cost savings are really not savings at all in the long run. On the trip when the motor died, my wife had actually been running premium but I suspect the damage had already been done, just had not lost compression yet. The final blow was the grade she was pulling when it finally gave out. She was going up the back side of the Tejon pass (the grapevine) heading south out of Bakersfield, Ca. on I-5. It is one of the steepest grades that I know of and had killed many a vehicle.

Thanks again, this is a great forum.

[albertj]

I drove that bit of I-5 many years ago, when I was a consultant... I had an assignment in the Mojave, decided to take the scenic route back to LA thru the Sierra Nevadas... Tejon Pass is a hill alright but it's on an interstate and not that steep -- BUT -- I think the reason it's a car killer might be related to the absolute elevation and the amount of time you have to pull pretty hard in progress to that elevation. It's 1499 feet above sea level at Grapevine.

There are nastier highway mountain passes. Back on March 3 I commented on driving from the Finger Lakes of NY to Pittsburgh via Williamsport/Altoona. This route goes through the northern Appalachians, crossing mountain summits near Mansfield (2000+ ft), Steam Valley, State College, Cresson (2000+), and the Laurel Highlands near Blairsville (2100+). Click the LINK (http://wjactv.com/news/local/two-multi-vehicle-crashes-close-stretch-of-i-99)to see what the intermission was like. What was happening was bands of snow, high winds and cold air were blowing through the mountains near Mansfield, Williamsport, and State College in bursts. The snow accumulated quickly, an inch would fall in a few minutes. On the road surface, initially it would melt but when the temperature tipped low enough it would suddenly ice over, as it had already been colder previously. Continuing to snow, then, gave us a layer of greasy slush on top of an icy pavement.... and then it got dark. And the squalls continued. Road salt does not work as well at night as during the day - see this LINK (http://www.clickondetroit.com/weather/thermoscope/when-does-salt-work-and-when-does-it-not)for an explanation.

My darling spouse did not need an explanation -- she just 'handed me the steering wheel' and said, "I'm done."

Yuck.

Weather was quite unsettled - we saw temperatures from the 40F to the 14F range in that stretch of the trip. Combined with the repeated squalls and the hills on the highway it was just, well, difficult.

The XC70, with its AWD and wearing Blizzaks, drove quite well through that smarm. Although, the TPMS started complaining... I am working on that.

Not sure there are many cars like the XC70. You may find someone else who wants to fix and keep it if you don't, or it could become a donor?

Best to you as you puzzle that out.

Albertj

[perkinscl]

Firstly, sorry to hear about your engine JPM. I'd be beyond disgusted if that happened.

Secondly, I'm kind of freaked out. I run regular/87 octane always, none the wiser. My 2.5T seems to run fine (145K miles). I switched to Premium for 1 tank and it didn't seem to make a difference, so I went back. Do I need to switch to mid or premium? For the rest of my maintenance, I try to keep up 100% with synthetic oil changes every 5K, Gibbons trans flush every 30K, etc.

[albertj]

Hi perkinscl -- I do not think you will see a difference in one tank. In my experience, takes 3 tankfuls of 91+ or better in a row for the ECU to reset the timing (or 'get the memo' so to speak). Best is if you have 91+ octane that does *not* contain ethanol, somewhat better fuel mileage with that although the extra cost makes it about a wash.

What I wonder about is how to get the old carbon out. Someone who's at least pulled several heads would have to comment on that one. I have heard that Techron is the best you can do without taking the heads off. :confused:

@JRL did you see this octane calculator (link) (http://www.wallaceracing.com/octane-mix-calc.php)? Just for fun. It tells you the resulting (calculated) octane depending on what you blend in your tank.

For the rest of you: the octane comments I made earlier are OK for "pump gas" you get on the street, but there's more to it. Here is a link to an explanation of octane from the racing fuel division of Sunoco. (http://www.sunocoracefuels.com/tech-article/beyond-octane) Before you quote anything in my post to your pals, better read that link... It's a quick read. :cool:

[v70+xc70]

Sorry, I'm rambling now. At least I know that I need to run premium fuel in these turbo motors from now on. Ran mid-grade when I first got it then got cheap and started running regular, so maybe this motor issue is my own fault?

Thanks to everyone for your input.

I don't think so. Wifey ran her 03/xc70s on regular for over a decade without issue until 127k. But then she is lightfoot except on the highway which was rare. That in itself was an issue for her car for different reasons. Car was totaled in Dec 16.

[kutcht1]

OK, so now I am confused as to what fuel I should really run in the XC. I have been just putting in the 91 octane since it has only been around $2.59 and I read that all turbos should use premium fuel. In the time frame of a year it really is not than much more cost to run so why chance it. Are most of you running 87 octane or midgrade? I run premium in all my vehicles maybe out of habit but maybe I am wasting my money.
TomK

[billr99]

OK, so now I am confused as to what fuel I should really run in the XC. I have been just putting in the 91 octane since it has only been around $2.59 and I read that all turbos should use premium fuel. In the time frame of a year it really is not than much more cost to run so why chance it. Are most of you running 87 octane or midgrade? I run premium in all my vehicles maybe out of habit but maybe I am wasting my money.
TomK

I ran my old '02 XC on 87 for the 8 years and the over 250K kms I had it with no issues whatsoever. In my '05 XC, I try to run 89 with an occasional 87 thrown in there when the price gets up there (yep, we still pay over $1 CDN per litre). Finally, in my '05 R GT I run 91 religiously even though I know 87 won't cause an issue but I like getting all the 300HP the thing can give me. I don't really drive any of these cars crazy any more but I'm not a light-foot either for what all that might be worth.

A few years ago when I had my Cdn-spec 850R (euro 247HP motor with M59 5 speed), I tried to run 91 but it was not always readily available where I lived (Northern Ontario) or rather good 91 wasn't readily available. In that engine I ran everything from 87 to 91 over the 250K I had it. Never had problems with detonation but I could tell performance-wise (as well as what the boost gauge showed) the difference between them all.

My point here is that Volvo is pretty good with their engine management software in regard to adjusting boost and advance to allow for the use of available fuel grades. On those Volvo motors with decent boost you can see a performance difference. On the low boost ones like in an XC, not so much so why not use the most affordable fuel?

Cheers,

Bill

[Sierra]

My personal belief is that you can pay at the pump - or pay down the road.

Paying down the road is always more expensive IMO - 91 Octane with gas that has a fuel injector cleaner like Chevron/Shell.

[Pennhaven]

I have to agree with billr99. IMO you are not going to hurt these engines by running lower octane. The knock sensor will detect spark knock and retard timing. Period. Though obviously you are losing potential torque/power.

That said, I personally run 89 octane most of the year. However, when knock is more likely, such as when ambient temperatures are high (85°F+) or when I am on a trip carrying a heavier load or putting additional load on the engine climbing grades, I will either use 91 octane or, when not available alternate fill-ups between 93 and 89 to achieve an approximate blend of 91 in the tank. I do that only to have more available performance, not to protect the engine.

[Jpm53]

Thanks to everyone for all the great info. So guess I am still wondering what caused this. If the engine management system adjusts for the fuel and some of you have been running regular for extended periods without any problem, what happened? I'm thinking maybe a partially clogged injector supplying a lean mixture to this cylinder (would think I would have had a misfire problem), or perhaps a piece of carbon on the piston getting super heated and causing the piston to melt? Any other thoughts? Just would like to prevent this in the future. Still love the way this car rode and drove. Can't imagine all Volvos being this troublesome or they wouldn't sell any cars? Would like to get an 06 XC in the future as I have read that they have a better AWD system, have less issues with the TCM, have corrected some other issues common to the 02's and I like the interior better. 06 is about the newest I can afford.

Thanks again for all the help.

Jon

[albertj]

@jpm33: there's info in what I posted explaining what happened. On the surface you're correct about the engine management system correcting for the available fuel. What you may have missed is the information in the links describing how detonation happens - carbon buildup and pre-ignition.

Not every driving style/situation leads to catastrophic failure, especially during the manufacturer's warranty period, and the topic is complicated enough to defy a quick summary.

Albertj

[MacNoob]

Volvo says in my 2007 manual: MINIMUM 87 RECOMMENDED 91

Personally I use 87 in the fall/winter/spring when temps are cool/cold and roads typically are too slippery to be heavy on the gas pedal. 89/91 when it's hot or car is heavily loaded. And my daily use is very easy on the engine - doesn't even get started without a minimum 30-minute drive, half 100 kmh highway.

[billr99]

@jpm33: there's info in what I posted explaining what happened. On the surface you're correct about the engine management system correcting for the available fuel. What you may have missed is the information in the links describing how detonation happens - carbon buildup and pre-ignition.

Interesting you should mention this as at one point when I had my '02 which ran nearly exclusively on 87, I scoped the combustion chambers and saw very little carbon buildup on the piston tops. They were nearly sparkling after I did a SeaFoam treatment (induced into the intake tract, etc.). Now there is more to all of that then just fuel octane level but the car had run at that point for nearly half its life on high sulphur, fairly bad Ontario fuel, synoil from day 1 and maintenance by the book more or less. Plus the car had very little idling in traffic and all of that kind of thing that could promote carbon buildup. Remember the XC motor is a low boost, not particularly high compression engine, all of which reduces the need for high octane fuel. I find it interesting that that particular page of the owners manual is the same for the all the models of the V70, at least in '05, regardless of low boost XC or higher boost R. Perhaps Volvo is trying to head off customer complaints because of the possibility of low grade 87/89 fuel in some of the markets it sells cars in?

Cheers,

Bill

[albertj]

Interesting you should mention this as at one point when I had my '02 which ran nearly exclusively on 87, I scoped the combustion chambers and saw very little carbon buildup on the piston tops. They were nearly sparkling after I did a SeaFoam treatment (induced into the intake tract, etc.). Now there is more to all of that then just fuel octane level but the car had run at that point for nearly half its life on high sulphur, fairly bad Ontario fuel, synoil from day 1 and maintenance by the book more or less. Plus the car had very little idling in traffic and all of that kind of thing that could promote carbon buildup. Remember the XC motor is a low boost, not particularly high compression engine, all of which reduces the need for high octane fuel. I find it interesting that that particular page of the owners manual is the same for the all the models of the V70, at least in '05, regardless of low boost XC or higher boost R. Perhaps Volvo is trying to head off customer complaints because of the possibility of low grade 87/89 fuel in some of the markets it sells cars in?

Cheers,

Bill

@MacNoob: OK.

@billr99: That's useful to know. BTW I've heard that SeaFoam and Techron are a couple of the chemicals known to effectively abalate built-up carbon in gasoline engines.

@jpm53: Did your friend scope and save pictures of the other cylinders?

...repeat from my previous post: Not every driving style/situation leads to catastrophic failure, especially during the manufacturer's warranty period, and the topic is complicated enough to defy a quick summary.

I am thinking, what do we learn from this thread?

[sjonnie]

Volvo says in my 2007 manual: MINIMUM 87 RECOMMENDED 91.

It also says to stand upwind while refueling and wear neoprene gloves while handling the fuel filler nozzle :eek:

[MacNoob]

Well, that sounds like a super-conservative safe recommendation....