Thanks in advance for any advice. My wife has a 99 V70 GLT that has 135K miles on it. I do all the maintenance and the car has had no major engine transmission issues to date (trans fluid every two years and Amsoil every 6K miles). About two years ago I noticed a little oil in the intercooler when changing out the radiator and some oil on the outside of the turbo. I bought the oil return line kit from FCP, installed it and the oil on the turbo went away (tubes and ports had no sludge). However, I still noticed the oil on the bottom of the intercooler by the weep hole. I just changed the oil a month ago and there was a little oil on the manifold. For the past week or so I noticed a slight ticking from the back of the motor on occasion. It was coming from under the heat shield covering the turbo. Everything was tight and the oil level was good, so because it has been single digit temps, I told my wife to just let the car warm up for a couple of minutes on really cold days until I could check into it.

Here's where it gets bad.
Tonight we were coming back from a short trip, car was warmed up and we pulled away from a light at decent speed. The engine light came on, it began running rougher, and the exhaust had a horrible smell to it (very acidic and sharp). She shut the car off and I looked under the hood for the typical things - leaking fluids, broken hoses, loose wires, etc. Nothing. Started the car and noticed a "thunking" noise that was at the rear of the engine. We limped home and the car just ran rough, but idled good and at ~ 800 rpm. Once in the garage I found the noise coming from the back of the engine right where the heat shield covers the turbo (same place ticking was coming from).

I am going to read for codes tomorrow and think I will find a turbo or waste gate issue. Any insight would be appreciated. How long do turbos last? I have run Amsoil since we bought the car in 01 ant the car is not "beat on". No metal on magnetic plug from pan or in any of the filters. Would PCV issue cause this? It is not pushing oil out all over, but did notice some on filler cap, a little on intercooler connections and on manifold below connections. No issues like pressure or leakage when pulling dipstick when running.

After the codes, what would you guys check next and how? I am a normally aspirated guy, but my wife has to have turbo Sorry about the long post, just tried to get you the details. Thanks

Dave
________
NATIVE AMERICAN SPIRITUALITY ADVICE

 

Not a turbo expert but from your very good description sounds like your turbo has died.

Would suggest using a stethoscope (long screwdriver held to your ear also works) to narrow the mechanical noise down to turbo or other part of your engine. If noise is definitely coming from turbo then take it apart find the bad parts..

 

Thanks for the reply gdog. I tried the screwdriver method and the noise is coming from the back of the engine or the turbo housing. I did get a read on the code and it is P0304. I have read that it is a misfire on the #4 cylinder. Does anyone know if that is correct and can it cause a thunking noise if the charge is not combusting at the right time or exhaust may be blocked by a failed turbo? One member replaced his coil packs and that solved his rough running issue and P0304 code, but I do not know if he had any noise coming from the turbo. Tomorrow (actually later today) I am going to pull the inlet to the turbo and see if the impeller is wiggling on the bearings and how much end play there is. I talked to a guy at Turbochargerpros and told me to try that. He said that the sound is probably the impeller hitting the housing and that the Volvo turbos typically fail in the bearing area.

Dave
________
Big Boobies

 

Let us know what you see inside the turbo.

Would also suggest cking the engine compression; #4 cyl in particular.

 

gdog,
I will look at the plugs and check the compression. I have looked up the code on other threads and the issues range from a bad spark plug, connector, coil, injectors, all the way to holes in pistons and burnt valves. Does a burnt valve fail slowly or catastrophically? We always ran mid grade fuel of a decent quality and only have put low octane in on occasion so I can't imagine a burnt valve. I am going to dig into it this weekend and will let you know what I find.
Thanks for the suggestion

Dave
________
3LATINASHOT

 

Began taking things apart today. Took off the inlet hose to the intercooler to get the cover for the coils and spark plugs. Found some oil in the hose at the connections and on the lip leading out of the turbo. Also come oil from the breather on the top of the head. I pulled the spark plugs and the #4 cylinder plug was dry and a greyish color. All the other plugs were somewhat black and sooty. Compression test revealed that all the cylinders pumped up 205 - 210psi (seems high, but they were all the same). Checked fuel injectors with ohm meter and all were the same. Checked for spark and #4 was dead. Swapped coil and had spark using one of the normal looking plugs. I bought a coil and hooked it up and the spark was back on the #4 cylinder. Just for fun I attached the old spark plug that came out of the #4 cylinder and it had a very weak, orange spark. Never seen a spark plug go bad like this. They usually work or don't. I'm going to put it together tomorrow with all new plugs and see what I get.

My question is: could the unburned fuel from the #4 cylinder have been igniting in the exhaust manifold and causing the thunking I am hearing? Or is this wishful thinking. Either way, we'll find out tomorrow. Stay tuned...
________
Fix ps3

 

Replaced plugs and coil and engine ran better, but thunking was still there and after clearing P0304 code, a check engine light came on and a new code showed up - P0305. Did quick check and now the coil was bad on the #5 cylinder! Replaced coil and it runs great now. Thunking noise was the heat shield covering turbo. It had broken an ear off and was bouncing around because of the vibration from the misfire. Never checked turbo because everything seemed to be running fine now

Would a blocked PCV system cause oil to be on the turbo outlet and pushed out of the breather cap? The hose from the top of the head to the side of the block was clean and had no restrictions. Would this be indicative of the rest of the PCV system condition? No pressure from dipstick.

Thanks
Dave
________
FERRARI COLOMBO ENGINE SPECIFICATIONS

 

Sounds like you lucked out regarding the mechanical noise and good job diagnosing the bad coills. Got to feel good having it running well again!

If the PCV system has never been replaced, i would do it just for preventitive maintenance if nothing else. Though i don't think that's causing the oil in the pressure side of your turbo; think the turbo are likely just a bit weepy at this mileage; not the end of the world but something to keep an eye on. From what I've read some oil in there is relatively normal.

 

gdog,
thanks for the support and technical advice. I'm glad it is running and that it was a relatively minor issue. Kinda wierd how one coil went bad after the other. It runs great and no noise - now I just have to shovel the 14+ inches of snow away from my back garage and access road to get the car out! I'm also going to replace the seal under the filler cap because it is no longer a soft, pliable rubber and some oil has come out of there. Take care

Dave

 

Ok so I get the car out of the garage for a test run and about 5 miles into it I get a stumble and a check engine light. Off to Advance Auto and read the code - guess what, P0302. My #2 cylinder coil is bad! I buy three coils and now all my coils are new and the car runs great. I also replaced the oil filler cap gasket and no leaks. Is it common for coils to fail about the same time? For the future, is it a safe bet just to replace all at once?

Dave

 

I have heard others say the same thing; once one coil goes bad, the others fail in rapid succession.. Don't understand it myself; maybe some engineer did a real good job of planned obsolescence??

 

Rapid succession is right!!! They must have really planned that good or quality control is spot on! I did some reading and a user called TECH has recommended on a couple of occasions that if one coil goes, replace them all. Seems like good advice in hindsight. Well, at least that is something that we won't have to worry about for awhile. Take care

Dave