35d worsening gas mileage - solved- thermostat/fan/EGR cooler - DIY with pics

[seattle]

Originally Posted by diegoX

Hi guys! Maybe off topic but does anyone know if the OEM EGR Cooler I will about to purchase from the dealer has been improved by BMW? I think mine just gave out and getting inputs if there's a better after market or just stick to the OEM which doesn't last. Thanks

What do you base your opinion about yours being bad?

[diegoX]

Originally Posted by seattle

What do you base your opinion about yours being bad?

Forgot the exact code but it has something to do with egr cooling system. At 90K miles I think it's time for replacement considering its a common problem. Thanks

[captpilly]

Finally took care of the T-Stat, Water Pump, Idler Pulley, and Fuel Filter today - took about 6 hours in total (My ABC's are missing). Thanks for the great directions - makes senses what you start poking around. I'm a C- mechanic but learning my way.

Only issue was that I replaced a seal on the lower red boost hose - it didn't seem to seat properly when I was under there and sure enough it wasn't set right when I drove off....

I can't quite figure out how to seat it properly - anyone dealt with this?

[captpilly]

Was able to get the boost pipe back on the following day - push up with right hand while pulling down with left hand. You will hear it click in.... total pain in the arse...

Temp is running solid 88-91 now - back in action.

[bfeng]

I haven't had time to do this on mine (73k miles). I tried a kludge for a 200 mile trip I took on Saturday where the ambient temps were around 15-20 degrees. I put thin cardboard over the radiator, leaving the center mounted ATF cooler exposed (and about 3" of the main radiator exposed). Even with this much blocked off temps never went over 74, which is 2-3 degrees above the without-cardboard situation. The efficiency of the cooling system is pretty impressive, eh? Anyway I remove the blockage and I just need to find a free Saturday to do the real fix. Just need some decent weather.

[daytonatrbo]

I have my parts on order to do mine. Coolant temps dipping as low as 65°C while driving in mild weather on the interstate.


Does someone have the torque spec for the aluminum water pump bolts????

[Dieseldonkey]

After change
My mpg up from 21.5 to 24.2!
This will pay for itself

[daytonatrbo]

Originally Posted by Dieseldonkey

After change
My mpg up from 21.5 to 24.2!
This will pay for itself

Where did you get your torque values for the water pump bolts? I don't see them in the OP and I don't have a working gt1 at the moment.

[daytonatrbo]

Originally Posted by Dieseldonkey

After change
My mpg up from 21.5 to 24.2!
This will pay for itself

Mine (preliminary) went from 18.6 to 25!!

[Stockx5]

Mine would not rise above 68c
Few distinctions that might be of interest:

1. Instead of the OEM I bought Beck/Arnley 143-0904 Thermostat Housing. from ebay member 3wardist for $44.67. housing is identical except for the serials and bmw logo. the internals are not the same. you can see oem on the left here and the Arnley on the right.
mainly the Arnley has a bigger copper core, and the springs have a lot less travel than OEM. Which one is a better part not sure but I will be happy to post when it fails.




2. 2 of my t-45 torx nuts on the egr cooler had already been replaced by regular nuts presumably by the dealer. After dropping the non magnetic flange bolts 3 times and finally losing one of them I went to home depot and bought the identical length/thread bolts. this is the size in case someone is wondering.


3.I noticed the EGR valve which had been replaced 18k miles ago by dealer with the updated part was completely caked up in soot. So was the throttle valve and so was the intake manifold.




This is what came of the EGR valve alone


Id be interested to see others egr valves to see if this is normal caking up procedure for diesel engines or if this was caused by the failed thermostat or if this is just what egr cooler does to our egines the car has 103k miles.

Either way it seems a glow plug/injector/EGRvalve/catalitic converter/dpf filter/engine would not last long if this contamination was being constantly pumped in.