2012 S60 T5 misfire problem
 

Car is about 111k miles. My wife was driving to another place and saw the check engine light after 1.5 hours drive. She went to Autozone near Vernon, CT and was told there was misfire on cylinder #4. Then she went to a close-by Jiffy Lube store.

The tech at JL changed all the spark plugs to NGK and told my wife it would be okay, but the issue came back right after a couple of minutes of driving. She had to go to another place so she left the car there.

Today, Jiffy Lube purchased another set of spark plugs and also replaced the ignition coil. Problem remained. They said they couldn't do compression test. I will have to figure out a way to tow the car back to my home (about 80 miles in MA). I joined AAA plus but that can only be used after 7 days. Is it possible to use that a couple of days before the 7 days?

Hopefully it is not the engine issue, although it is quite likely. We used premium gas (#93) for years, but last year my wife decided to use #87. It has been okay since then. Yesterday before the long drive, I filled up with #93. Could this be a cause or trigger?

Thanks for any input.

Probably, it could be issues with fuel injectors, wires, or even a vacuum leak, given its mileage.
Switching from #87 to #93 is unlikely the main issue, especially if the engine ran fine on #87 before. Though different fuel types can affect engine performance, it’s usually not enough to cause a misfire.

Plus, if you can, try a compression test to check the health of the engine.

Worst news. The car was towed to a local garage and I was told that 0 compression on cylinder #4. They don't suggest any more work on this. An used engine swap could also take 5000+ dollars.

Any other ideas?

How do I even get rid of it now? https://www.matthewsvolvosite.com/fo...icon_e_sad.gif

really depends on the cause of the compress loss. Usually that's a dry then wet compression test (wet means a small amount of oil is added to the chamber to help the rings seal up. If the wet and dry tests are the same then its likely a valve issue. Another test is to do an inspection cam - which can look at the valves and the piston top and cylinder walls. Usually piston/ring problems lead to oil consumption and perhaps a slight loss of compression (say down to 100 vs 150 PSI). Zero compression would suggest a valve issue, which in your case may mean you need to get the head rebuilt vs pulling the engine. Still not cheap - my guess is 2500 give or take.

Thank you, mt6127. If 2500, I would take it. Given we are in the Boston area, I would expect 5000 or so. That doesn't seem to be worthwhile anymore.

a few things you can do. 1) get a shop to do a proper diagnosis to determine if its a burnt valve (fairly common) vs something piston/ring related. 2) use car-part.com to get an idea of the cost to buy a used replacement head (probably cheaper than a rebuild but not as reliable). 3) use KBB.COM to determine the book value of your car 4) get a shop to give you a quote to replace the head (like doing a head gasket job). Once you have this info you can determine whether the cost to repair is worth more than the car or you can try and sell as a "mechanics special" - which assumes the car's work is book value minus the cost to repair.

Thanks. I just drove the car back from the shop. The drive was rough but not too bad. I plan to buy or lease a new car.

Just curious: if I drive the car for a few miles occasionally to take my kids within town for activities, what is the risk for doing that for a few weeks?

Curious what the shop said is going on?

They just said cylinder #4 had no compression at all. They checked all spark plugs and coils which had no issues. What else should I ask them?

With no compression, replacing the fuel injector does not help at all, correct?

no compression at all in one cylinder usually points to a burnt valve (easy enough to see via an inspection camera). To fix the head needs to come off and either get rebuilt or replaced with a used part. I supposed you could drive it for short distances - the risk is you will be pushing unburnt fuel into the exhaust which can mess up you O2 sensors and the catalytic converter so you'd want to keep it to a minimum. I'd say the next step is to ask around for shops that will replace a head on a Volvo. A google search suggests a head gasket job costs $2000 give or take, so add the cost of buying or rebuilding a cylinder head to that (I'd budget 500-1000). Assuming your car is in good shape, its probably worth about $6K so investing $3K for a repair is not out of the question.