Just bought a 2002 Z3.. Which under bonnet plastics should I replace/take a careful look at ?

Ade33

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I've read that since these cars are now a minimum of 20 years old that I may have problems with various under the bonnet items since many are plastic/rubber and will be brittle and could fail...As i'm a complete newbie to the world of Z3s could somebody enlighten me if this is true and if so should I look at replacing anything automatically to prevent problems down the line?
 

Ade33

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Only that it's got a FSH with stamps in the book from new with mixture of main BMW dealer for first 6 years then independents since then.. Previous owner had it for 10 years and used it as holiday cruiser going round Europe most years
 

Jack Ratt

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Check the intake plastics/rubbers for splits or cracks. If it's running ok and idling ok then all will most likely be good.
 

colb

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Z3's and Z4's all suffer from age related problems with rubber and plastic degrading usually down to repeated heat cycles over the years. Rubber intake boots from the air filter to throttle body are the most likely to develop splits or tears so keep an eye on their condition. Any of the plastic vaccum pipes across the engine also need to be checked for cracks or splits. O rings also degrade over time and develop leaks as do some of the gaskets used between componants on the engine. Not only can these result in oil leaks but also allow air into the vaccum system which usually manifests itself in poor running and fuel trim issues that often result in engine management light being lit. Prime examples of gasket fails are the oil filter to block gasket, Cam cover gasket and Dip Stick O ring failing. Some of these leaks can be hard to spot visually so probably best to smoke test the engine which will reveal where the leaks are. Sump gaskets can also be prone to developing oil leaks due to age of the gaskets.
 

Ade33

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Z3's and Z4's all suffer from age related problems with rubber and plastic degrading usually down to repeated heat cycles over the years. Rubber intake boots from the air filter to throttle body are the most likely to develop splits or tears so keep an eye on their condition. Any of the plastic vaccum pipes across the engine also need to be checked for cracks or splits. O rings also degrade over time and develop leaks as do some of the gaskets used between componants on the engine. Not only can these result in oil leaks but also allow air into the vaccum system which usually manifests itself in poor running and fuel trim issues that often result in engine management light being lit. Prime examples of gasket fails are the oil filter to block gasket, Cam cover gasket and Dip Stick O ring failing. Some of these leaks can be hard to spot visually so probably best to smoke test the engine which will reveal where the leaks are. Sump gaskets can also be prone to developing oil leaks due to age of the gaskets.
Thanks for this it's really helpful. I noticed on the inlet manifold? What looks like a rubber bung cap covering a small pipe that is split.. Does this sound familiar?
 

colb

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Take a picture of that and post it on here, it may be a blanking plug as its not connected to something your car isn't fitted with. As to blanking caps its always worth checking the rear of the inlet manifold, that has some rubber caps on some stubs under the back edge and these split and fall off which allows unmetered air to get in causing havoc with the fuel trims.
 

colb

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Beat me to it with the picture, yes thats a blanking cap so replace it with a new one or its going to fall off and cause you running problems, quick fix is to wrap some insulating tape around it to seal and tighten its grip on the stub.
Realoem parts site link, items 15 and 17
 
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Eddie Zedder

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Beat me to it with the picture, yes thats a blanking cap so replace it with a new one or its going to fall off and cause you running problems, quick fix is to wrap some insulating tape around it to seal and tighten its grip on the stub.
Exactly what I did with mine, and it's still like that 7 years on o_O
 

Ade33

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Brilliant thanks ever so much.. And also for putting the part I need. I'm completely new to BMW Z3's.. A complete novice.. So to get help from folk that have knowledge is great.. I also run a 1971 Triumph TR6 for 15 years and know a lot about keeping one of those going but the world of BMW M54 engines apart from sharing 6 cylinders with my Triumph is a whole new world!!
 

Z Victor 1

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Although 63k is not a lot it is 20 years old as you say. I'd be thinking of replacing the water pump, complete thermostat etc, as the plastic parts go brittle with age . Pity you haven't got any real history/bills etc. Stamped books don't really tell you much.
 

Zephyr

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Before starting all this preventative maintenance I would scan for codes first.
maybe something evil lurks in the shadows and needs to be addressed prior to these expenses.
 

colb

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Z3 M43 1.8 (1999) and Z4 E85 2.5 (2003)
Since the Z world is new to you probably best to invest in a code reader you will need one sooner or later, I use a Creator 310+ handheld scanner which is a very capable tool. You can also go down the Laptop based diagnostics road and use BMW INPA and BMW Scanner 1.4 diagnostics. INPA best run on an old laptop with Windows XP, can be a bit of a faff configering INPA up but BMW Scanner 1.4 is far easier to install and use. Worth noting is that there are two diagnostic sockets on Z3's the 16pin OBD2 socket under the steering wheel will only read engine and gearbox modules. The 20pin round socket in the engine bay will access all modules on the car but to plug whatever diagnostics you have you will need a 20pin to 16pin OBD2 cable changer to use the round diagnostic socket. All the software and indeed the cable changer and the Creator 310+ are available on ebay for little outlay.

That link to parts I posted is from Realoem parts site which is a great resource, Go to the home page and enter the last 7 letters and digits of your Vin number and it will display the parts applicable to your car when it left the factory. Explore all the sections, really useful to find part numbers.
 
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