I bought a 1988 Volvo 740 turbo. I really like the car, but it has a few issues. And I would really appreciate some insight to know what my problem is.
The first one is that once in a while it smokes through the tail pipe. It completely unpredictable when it will happen and it happens for about a minute. Thick smoke. Once it was kind of dark, lately is always kind of white. My friend says that it smells funny, it haven't happen in the last 15 days, and always stops in about a minute and the engine never has any trouble starting or running, it is annoying because it is very thick smokes that makes the car looks like it is burning. I don't know if this may be related but each time the turbo engages I detect a faint smell in the driving compartment (the turbo works perfectly). I am not sure but also it seems to me that when driving in the thruway, my car looses oil, maybe because of the turbo engaging. I had to add half a quarter of oil after a ~300 miles trip, while driving in the city I had driven about 500 miles without losing any oil (I was checking every day, because the seller told me the front seal in the motor had a leak, I am not sure, or else it only shows when the turbo engages a lot like in the thruway). I wonder if the problem is that the turbo is leaking oil somewhere and then it goes into the tail pipe, but the smoking anyway only happens very irregularly, sometimes like 2 days in a row (1 minute smoking) then nothing for 2 or 3 days, then again 15 days later. Everytime just for about a minute and then stops and the exhaust is transparent regardles of how I drive (turbo-no turbo). The motor runs well at all times even when smoking. I wonder if this is something I should worry about. Is there any place where the antifreeze can reach the turbo or exhaust? I was wondering about that when my friend told me about the funny smell, I had never notice any smell (I am not very good smelling stuff).
The second problem, is electrical. After a couple of weeks with the car the charge in the battery seemed to start dropping and every day was less. It always started, soon after that, the alternator belt broke and I replace it so I thought it was maybe the belt, but then the problem still was there. Now every time I run the car on the alternator goes to ~14-15V, then when I stop the voltage reads about
12-13V, and after several hours after I return to the car right before starting the car the voltage is between 10 and 11V. I check with an A-meter in series with the batery and when the car is off the current is only 11mA which I think shouldn't discharge the battery. Also, I when to an Autozone and they check the battery and said that according to their tester the alternator, battery and diodes where in good shape (the test was done accelerating to 2000rpm). I anyway changed the battery for a new one, but it still has the same behavior.Any help would be greatly appreciated, thank you very much.
Carlos Henry