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Followup To
Question - I pipetted some coolant out and it's normal green antifreeze, then I checked the oil, and it's way over the second line. If the oil is over full, and smells like fuel is it possible that they overfilled it during oil service last Nov? I haven't checked it since they serviced it 11 Nov 05, until now, so I don't know if it was overfilled or if it's fuel. The color and texture is normal, but seems thin because the wind was blowing it off the dip stick all over the place.
Wouldn't the compression test show leaky piston(s)? Wouldn't all the diagnostic computer testing they've done tell that it might have this problem? The car runs fine but for the adjustment they made that makes the car start at 1500 rpms. It sounds like it's yelling when it starts, unlike before. They didn't replace the Air Mass Meter, just take it out, try a new one in and decided that the old one wasn't broken.
I'll get somebody over to check the oil before I drive it again. I really don't want to ruin it.
Thanks again. Teresa.
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Followup To
Question - Ok, I'll check the oil and coolant in the morning. I should tell you that before they concluded it was the catalytic converter they also checked and charged me for the following:
Remove and install or seal rocker cover
Check breather pipes
Repair one pipe
Check compression of all cylinders
Remove and install left or right air flow meter
Special exhaust gas emmision test
Adjust position of lambda
Engine test using dynamometer
Replace engine vent line
Check fuel pump delivery pressure
Remove and install air cleaner
Fuel system open time
Remove and install catalytic converter
Check engine idle speed and CO
Adjust idle speed,fuel/air mixtures and CO
Does any of this make any sense? This same shop has been changing my oil regularily, did a minor tune up this past summer, and recently replaced the thermostat. I would expect that the mechanic would have noticed any real problems at one of those times. What I swiped out of the antifreeze was like a piece of wax, I don't think the oil would turn into wax like that.
All of the above should explain my frustration. What would clog a catalytic converter up? Is it normal for them to require replacement every 100,000 miles, or so? Or could it be the result of a bigger problem you mentioned like the pistons, or the head gasket? What do repairs like that usually cost on average?
I love my car and I'm not giving up so easy. You have been a fantastic source of knowledge and great emotional security throughout this ordeal. I can afford the repairs, but I just want to ensure they are the right track.
Thanks again. Teresa.
Hi Josh,
I wrote last November about the Check Engine light on my 1995 525i. I thought the problem went away after the O2 sensor was fixed/replaced a third time under warranty. I really believed that everything was taken care of. After a short time the Check Engine light came on again. Finally, I agreed to let them replace the catalytic converter because the car started to run badly and acted like it had serious breathing problems. They were certain that it was the catalytic converter because the mechanic took the exhaust system off and the car began to run normally. I have been impressed with the car's performance for about a month.
Last week the SRS light came on. Today, the Check Engine light is back on. Before the Check Engine light came on I noticed there was more than normal white exhaust. This also happened before the catalytic converter was replaced, but the car seemed to produce a normal amount of moisture in the exhaust after replacement until today. The temperature gauge is straight up just like it should be.
I took the radiator cap off while the car was running, no problem, it had pressure, but I noticed a piece of wax float to the top. I swiped it out with my finger. I think maybe the floating wax was from the thermostat recently being replaced because the car was running cold most of the time. Then I checked the oil, it was not white or filmy, it was normal, but it smelled like fuel. I have noticed that the car is still using twice as much fuel than it did a couple of years ago.
I have already scheduled service for next week because of the SRS light. When they see that the Service Engine light is back on, after all that work they did, I think they are going to suggest that the Engine Control unit is bad. They already tried a new ECU and a new Air Mass meter before they replaced the catalytic converter and decided that it wasn't either the ECU or the Air Mass meter, so they didn't charge me.
I plan on keeping this car. It's a BMW! This model has so much more class than the newer models. I have maintained it and it's served me well. Unfortunately, I am stationed overseas until May 2007. I am willing to spend the money to replace the ECU if that's what the problem is. I don't know why the car continues to have problems. Could it be the fuel? I use unleaded 90 octane. It's all I can get here.
I trust the mechanics at this BMW dealership, but I really would appreciate your advice, so I can make an informed decision. Sincerely, Teresa.
Answer -
Teresa,
Some of these BMW's had trouble with the SRS system, there are several sensors that can trigger the SRS light to come on. Most of the time it's something minor. The technician should be able to tell which sensor is setting the SRS light off, and it would be different from the Check engine problem.
First off, the car is over 10 years old, so it's about time to start showing some trouble. I dont mean it's going to leave you stranded, but you will start to see little things pop up like this. It's all part of owning a 10+ year old car. Unfortunately with out seeing a the actual scan tool that the dealership is using I cannot make any assumptions as to your problem.
You said there was a piece of wax in the coolant. Are you sure it was not OIL? If you have oil in the coolant, or coolant in the oil (as you already checked... good job!) then that would make me suspicious of a blown head gasket. It doesn't always work both ways, as you migh have oil in the coolant, but no water in the oil.
If the oil smells of fuel, check the level and make sure it's not too high on the dipstick. Secondly, this could mean your piston rings aren't sealing well and letting fuel pass down the side of the piston(s) and into the oil.
In summary, I would let the car sit over night, and check the coolant BEFORE you start the engine. See if there is any oil floating in the coolant tank. Also after the car has set over night, check the oil and make sure there the oil level is ok (between the two marks).
Hope this helps,
Josh
Answer -
Teresa,
I hope the guys really did all that they wrote down. Most places dont have an Engine dynomometer, so it seems they are a very well equiped shop.
I understand everything that was done, and it seems very thorough. I'll go through them for you in "english"
Remove and install or seal rocker cover: you had an oil/vacuum leak on the valve cover, they replaced the seal
Check breather pipes: self explanitory
Repair one pipe: ditto
Check compression of all cylinders: they remove a spark plug and put a "mock" spark plug in it's place, this plug has a hose attached to a gauge to measure the ammount of PSI that your pistons compress. VERY good tool to measure how your engine is running. The lower the number, the more leaks your piston has around it. You want a good high number on this (175psi+)
Remove and install left or right air flow meter: apparently they replaced the AFM (air flow meter). This tells the on-board computer the ammount and temperature of air coming into the cylinders, so fuel ammount can be adjusted to match.
Special exhaust gas emmision test: Not sure about this one?
Adjust position of lambda: Lambda simply put is the reading the O2 sensor gives the computer. Looks like they adjusted it
Engine test using dynamometer: Its a performance test, where they roll the car onto big drums an use the tires to spin these drums. This tells them how much torque and horsepower your car is making. It's a powerful tool to adjust how your car is running. Most racecars use these to get every ounce of power out of the engine.
Replace engine vent line: self explanitory
Check fuel pump delivery pressure: The fuel pump is located in the gas tank, and has an electric pump that forces fuel to the engine via a rubber hose. They disconnect the hose and attach a gauge to read how much pressure the pump is making. If the pump isn't making enough pressure, this could be a problem
Remove and install air cleaner: put a new air filter in.
Fuel system open time: Not sure on this one?
Remove and install catalytic converter: self explanitory
Check engine idle speed and CO: they used a computer to check how high/low your engine is idleing.
Adjust idle speed,fuel/air mixtures and CO: they adjusted the Air/Fuel ratio (usually 14.7:1 for the average car) Not sure why they needed to do this, since they replaced the Air Flow meter already.
Over all it seems like these guys know what they are doing, I just hope they aren't cutting corners.
Hope this helps,
Josh
AnswerTeresa,
It is VERY possible that the guys overfilled the oil the last time you had it changed. All it takes it to loose count of the ammount of oil you've put in. Unfortunately Checking the oil, is not "cut and dry", you need to know how to check it correctly. To get the most accurate reading, let the car sit for at least 2 hours before checking it. When you drive the car it slings oil all over everything, and the oil reading wont be correct until all of that oil has run down to the oil pan again.
So let the car sit for a few hours prior to checking the oil. Pull the dipstick out and wipe it off with a CLEAN papertowel or old rag. Once the dipstick is clean, reinsert it back into the dipstick tube and fully seat it. Pull the dipstick back out again, and now you should get an accurate reading. Sometimes oil gets up in the dipstick tube, and runs down the dipstick, making a false reading, that's why it's so important to wipe off the dipstick.
Reading the dipstick is easy as well. The two marks on the dipstick denote "1 quart" of oil. So if your engine only held 4 quarts and the oil level was at the bottom line, you have 3 quarts in the engine. If the level is at the top line (closest to your hand) the oil is FULL.
I've seen places over fill the oil before, and it's not great for the engine. It will usually burn some of the oil, and that will eventually clog the catalytic converter.
So double check the oil level, using the procedure I showed you, and you will get a clean reading. If the oil is above the top line, I would drive back to the place you had the oil changed at and complain. That would be rediculous and embarrasing for a mechanic to over fill an engine with oil. Simply put... he should know better.
Hope this helps,
Josh
