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Discussion Starter #1
Hey all,
New to bmw with a 00 328i, and so far I have just replaced a control arm, cam pos sensor, and oil. Ignoring the rear differential thud noise for now, but it's at 108k miles, so it's general maintenance time. I have SES codes below that are I read with my generic code reader. I am about to replace my upstream 02 sensors, fuel filter, MTF (using Red Line MTF), belts, and tensioners (Not yet sure if I have a hydraulic or mechanical tensioner for the water pump/alt belt). In addition I am going to replace my upper and lower radiator hoses, thermostat and assembly, and one hose from the expansion tank to the heater core. The hose clamps are new to me. So, a few questions to you E46 fanatics...

Is there a post or pointers on how to remove the bmw coolant hose clamps properly?

Is there a good posts or recommendations on properly bleeding and refilling the coolant system as to avoid getting air in the system?

Should I change the Expansion Tank (Doesn't appear to be leaking)?

Should I change the water pump?

Should I get the BMW coolant or just coolant from the parts store?

Please let me in on any pointers or advice you may have for this maintenance task.

I recently purchased this car, and if I am forgetting any 100k miles maintenance please let me know. I am going to replace the upstream 02 sensors and fuel filter, and at that time better evaluate the hoses and see what type of belt tensioner I need to get for the wp/alt belt drive. Parts are on order and I should be starting soon.

The SES codes:
P1250: fuel-trim
P0173: fuel-trim malfunction (bank 2)
P0170: fuel-trim malfunction (bank 1)
P1188: Oxygen Sensor High Resistance Upstream (pre-cat) / Fuel Control Bank 1 Sensor 1
P1189: Type 1 Low Resistance Upstream (pre-cat) / Fuel Control Bank 2 Sensor 1
P1478: Evaporative Emission System Leak Detected (very small leak)

Thanks,
Ben
 

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Here is a good DIY that should answer many of your questions including filling and bleeding the cooling system:
http://www.bmw330ci.net/maintenance/completecoolant.php

If you follow these directions and fill the expansion tank very, very slowly, you should not have any problems with air in the system.

The hoses use a spring clip that locks into the mating part. Just lift the spring clip up and pull the hoses off. It will be easy to understand once you look at the replacement hoses. It sometimes helps to spray the connection with WD-40 to help release the O-ring inside the hose.

Most people consider the expansion tank and water pump to be consumable items that should be replaced every 80K to 100K miles. I replaced mine.

Most people recommend BMW coolant and distilled water. One gallon of each is all you will need. That is what I used.

Other tips:
Plan on replacing the coolant sensor in the lower radiator hose. If you re-use your old one it will probably leak. You can also just replace the o-ring on the old sensor if you can find the correct size.

If you have an automatic trans, plan on replacing the trans fluid thermostat at the bottom of the expansion tank. These typically break when you remove the tank.

Be careful when removing the water pump pulley, it can easily be broken. If it doesn't pull off easily, soak the hub with penetrating oil (PB Blaster or Liquid Wrench).
 

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Hey all,
New to bmw with a 00 328i, and so far I have just replaced a control arm, cam pos sensor, and oil. Ignoring the rear differential thud noise for now, but it's at 108k miles, so it's general maintenance time. I have SES codes below that are I read with my generic code reader. I am about to replace my upstream 02 sensors, fuel filter, MTF (using Red Line MTF), belts, and tensioners (Not yet sure if I have a hydraulic or mechanical tensioner for the water pump/alt belt). In addition I am going to replace my upper and lower radiator hoses, thermostat and assembly, and one hose from the expansion tank to the heater core. The hose clamps are new to me. So, a few questions to you E46 fanatics...

Is there a post or pointers on how to remove the bmw coolant hose clamps properly?

Is there a good posts or recommendations on properly bleeding and refilling the coolant system as to avoid getting air in the system?

Should I change the Expansion Tank (Doesn't appear to be leaking)?

Should I change the water pump?

Should I get the BMW coolant or just coolant from the parts store?

Please let me in on any pointers or advice you may have for this maintenance task.

I recently purchased this car, and if I am forgetting any 100k miles maintenance please let me know. I am going to replace the upstream 02 sensors and fuel filter, and at that time better evaluate the hoses and see what type of belt tensioner I need to get for the wp/alt belt drive. Parts are on order and I should be starting soon.

The SES codes:
P1250: fuel-trim
P0173: fuel-trim malfunction (bank 2)
P0170: fuel-trim malfunction (bank 1)
P1188: Oxygen Sensor High Resistance Upstream (pre-cat) / Fuel Control Bank 1 Sensor 1
P1189: Type 1 Low Resistance Upstream (pre-cat) / Fuel Control Bank 2 Sensor 1
P1478: Evaporative Emission System Leak Detected (very small leak)

Thanks,
Ben
On the MTF, I wouldn't do it. Factory diff and manual tranny fluids will last a long time, well past your mileage. If you do want to replace them anyway, I would recommend using BMW factory fluids. They seem to hold up much better over time.

There is a bleed screw that you use to bleed the coolant system. It is right next to the expansion tank, a phillips screw made out of plastic.

If your expansion tank seems fine, I would say, leave it alone.

When you remove the fan and belts, check to see how the waterpump feels and if its leaking fluids around the edges. If not, I would leave it alone. (Just did a waterpump at 165k miles and it looked perfect)

BMW or Audi equivalent G11 coolant. They are both the same coolants. Pentosin makes such coolant.

If you are getting fault codes, be ready to have a diagnostic tool to reset after changing the O2 sensors.

Change your belts and rollers.

Change your fuel filter.

Air filter and cabin filter can be changed based on scehduled maintenance.

Good luck.

Raj
 

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Discussion Starter #4
Thanks guys for the helpful information. I will probably just examine the water pump and expansion tank, and just plan to do that at a later time if I can get away with it. I called the dealership and they have the coolant for $20, so I will get that and some distilled water too. I can't find just the o-ring for the coolant temp sensor in the lower hose... I guess I have to just order the sensor or hope it doesn't leak if I reuse the existing one?

There are a couple of things I am still unsure of... Is there a way to know without taking anything apart, what type of tensioner my car has for the wp/alt belt? I see there is a hydraulic and a mechanical tensioner. Can I replace whatever I have with a mechanical one? (http://www.realoem.com/bmw/partgrp.do?model=AN52&mospid=47641&hg=11&fg=18)

I noticed my car has green coolant in it.. Should I drain it and run some distilled water through it, and drain it again, or would just letting it drain and then filling be good enough?

Thanks again!
 

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This thread has information on o-rings that can be used for the coolant temperature sensor in the lower hose:
http://forum.e46fanatics.com/showthread.php?t=711333

I know that a mechanical tensioner can be replaced with a hydraulic tensioner with the correct mounting kit. I would guess that a hydraulic tensioner can be replaced with a mechanical tensioner, but I don't know that for a fact.

If you drain the block, the expansion tank and replace the hoses, you will remove most of the coolant. There won't be much old green coolant left in the system. Flushing with distilled water is probably the best solution, but it may not really be necessary.

Regarding whether or not to change the water pump and expansion tank, I replaced mine, but I admit they both looked perfect. However, a number of people have posted threads about expansion tanks cracking on higher mileage cars. I considered it cheap preventative maintanence.
 

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Since your going to be in there, you may want to do the VANOS seals that Beisan Systems sells. Your going to have 30% of the intial dis-mantling done anyways.
I just did it on my car at 100K miles and WOW! The difference for me was dramatic. Raj is a great guy and even answered my email questions very promptly. Highyl recommended.
I would also agree with the other poster.... if the water pump feels tight and isnt weeping, leave it. I havent changed mine yet. Also, I decided at 75K to change diff and MT oil. I went with Royal Purple, and it seemed to help with smoothing out the 1st-2nd shift. My 0.02.
 
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