[HighlandPete]

Originally Posted by superflyguy9

So I am screwed then - as it sounds like this is the only thing left to do?

One chap mentioned the "Top Hose Thermostat Modification" in a previous post and that worked successfully- as I undertand this is inserting a "Thermostat" into the top hose preventing any Bi-pass situations. I searched and searched for this but couldnt find the spec or DIY on how to do this and with what parts - or is it safe to do versus the "costly" gearbox heat exchanger repair?

Is there anything else I can do / try to diagnose my low coolant temperatures Definitively??

Thanks again for your help

Not so sure about a top hose 'in-line' thermostat. I know the Rover 75 guys do so with the BMW engine, but they don't have EGR thermostats, so a little less coolant complexity. But there is a delay in how an external thermostat responds, all depends on how big the bleed hole is and as soon as it is big enough, there is also a leakage of heat again. I'm not sure I'd want any delays in coolant performance, particularly on hot days, or when having a DPF regeneration.

Plus you really want the main thermostat working properly anyway, it's of the by-pass type (has a by-pass plate fitted). So when fully open under hot conditions, the plate valve closes off the reduced flow by-pass circuit and ensures the coolant circuit changes to full radiator flow.

The real issue is in checking the oil cooler thermostat. You'd need to clamp the hose that loops it to the radiator. Difficult to get at, but as it also shorts across the controlled by-pass coolant circuit, introducing cold coolant, it will cause very slow warm up and prevent optimum ECT.

HighlandPete

[superflyguy9]

I will give this a go then Pete - presumably I need to locate the water pipe from the gearbox to the radiator, clamp it, run the car for 10-15 minutes and monitor the ECT?

thanks again Pete

[HighlandPete]

Originally Posted by superflyguy9

I will give this a go then Pete - presumably I need to locate the water pipe from the gearbox to the radiator, clamp it, run the car for 10-15 minutes and monitor the ECT?

thanks again Pete

Not the gearbox lines, but the coolant hose between the radiator and heat exchanger, (part 9) or the hose out to the return flow into the thermostat housing.

Probably easier to get at hose (part 7), but clamp somewhere near where the number 8 is placed, before it tees into the top section.

http://www.realoem.com/bmw/showparts...14&hg=17&fg=05

HighlandPete

[superflyguy9]

Originally Posted by HighlandPete

Not the gearbox lines, but the coolant hose between the radiator and heat exchanger, (part 9) or the hose out to the return flow into the thermostat housing.

Probably easier to get at hose (part 7), but clamp somewhere near where the number 8 is placed, before it tees into the top section.

http://www.realoem.com/bmw/showparts...14&hg=17&fg=05

HighlandPete

Thanks again

[superflyguy9]

Originally Posted by HighlandPete

but clamp somewhere near where the number 8 is placed, before it tees into the top section.

http://www.realoem.com/bmw/showparts...14&hg=17&fg=05

HighlandPete

Hmmm. Was thinking, now I have seen the "Top Hose inline thermostat modification" information. IF it proves to be the case that when i clamp the pipe, I get normal ECT, then if that part is so costly to replace could there be an opportunity to put an in-line thermostat into the pipe below the Tee section that feeds the oil cooler? an 88 degree stat? could that work?

[les330]

Hi
Have 2006 e92 330 auto & just visited main dealer who can check coolant temp on key reader & showed temp at 71 degrees. MPG running at just over 30mpg in London so thought I would check. When I queried defective stats they said that if there were any faults it would show on engine management system, which it hasn't. Basically do stats need replacing?
Thanks

[coopersim]

Originally Posted by les330

Hi
Have 2006 e92 330 auto & just visited main dealer who can check coolant temp on key reader & showed temp at 71 degrees. MPG running at just over 30mpg in London so thought I would check. When I queried defective stats they said that if there were any faults it would show on engine management system, which it hasn't. Basically do stats need replacing?
Thanks

As far as I know, stats don't generate errors, neither has an electronic connection to it, purely analogue devices.

Low temps cause poor mpg and lack of DPF regens, if the dealer won't fix it, do it yourself for around £100

The number of affected cars, this issue really should be a sticky to raise awareness before hundreds of cars need new DPF's

[HighlandPete]

Originally Posted by superflyguy9

Hmmm. Was thinking, now I have seen the "Top Hose inline thermostat modification" information. IF it proves to be the case that when i clamp the pipe, I get normal ECT, then if that part is so costly to replace could there be an opportunity to put an in-line thermostat into the pipe below the Tee section that feeds the oil cooler? an 88 degree stat? could that work?

Interesting idea. Subject to getting a suitable fitting it would work in stopping/slowing coolant flow. But...

It is a bit remote from the heat exchanger, where the oil temperature is the trigger for the thermostat. You'd not be surrounding the thermostat with accurate enough sensing. Would be a gamble to whether you had any or sufficient oil cooling when necessay. Overheating the transmission oil will reduce its performance and life expectancy. Now that would be expensive, if it caused a gearbox pre-mature failure.

HighlandPete

[HighlandPete]

Originally Posted by coopersim

As far as I know, stats don't generate errors, neither has an electronic connection to it, purely analogue devices.

Low temps cause poor mpg and lack of DPF regens, if the dealer won't fix it, do it yourself for around £100

The number of affected cars, this issue really should be a sticky to raise awareness before hundreds of cars need new DPF's

Can of worms, when we rely on the garages to identify diesel engine thermostat failure, or low 'opening' temperatures. (Different with MAP thermostats in petrol engines).

Even when there are DPF issues, and garages are supposedly diagnosing the 'fault', there doesn't appear to be any link/flag up back to low ECT. The reports show it gets missed, even replacing the DPF in some instances, to find the same issues come back in short order. I wonder why?

It does appear it is the garages who have learned the hard way, who then know what they are looking for.

From many of the experiences reported on the forums, the typical garage just run a car in the workshop, it gets hot, so that means there are no thermostat issues. They are able to enable a forced regeneration, (if necessary) engine gets even hotter, that "proves" there is no issue with low ECT, "fixed".

HighlandPete

[confused.com]

Originally Posted by coopersim

Autodata states a couple of hours labour, plus about £80 for genuine parts (other members have mentioned not to bother with non genuine stats)

I ordered parts; 11517805811 £40.24, 11717787870 £29.94, 83192211191 Antifreeze £8.70 (this is for a 325d)

Thanks Coopersim.

Are you or anyone else able to confirm if these are the part numbers i need for an 08 e92 335d? I assume its the same, but just before i commit and buy.

[coopersim]

Presuming it's a March 08 car:

http://realoem.com/bmw/showparts.do?...65&hg=11&fg=35

http://realoem.com/bmw/showparts.do?...97&hg=11&fg=50

Same parts

Dealer will confirm from VIN number when you order

[confused.com]

Thank you, will get them ordered.

Just waiting on birds to give me a quote for labour, i already have one from another indy for 156 inc vat.

[coopersim]

My indy quote was £130 (two stats, 6 glowplugs), on the proviso I supplied EVERYTHING - including coolant

I spent £85 on tools in the end and did that and my glowplugs

[confused.com]

yep, this was 130 ex vat, im assuming yours was too?

I'll be supplying the parts too, might aswel take the hit and get it done now, i wont be able to stomach a 1500 bill to fix a knackerd dpf.

I think a few people have mentioned the car becomes a little more responsive after this? have you noticed anything?

[coopersim]

Mine was £130 all in, I am oooop norf though

Can't say I've noticed any improvement yet, but I was half asleep on the way in this morning

[confused.com]

Just to report back, had both stats changed today and the car was reaching 90 -92 on a brisk drive! Previously it was reaching 83/84.

Thanks coopersim for the part numbers.

[coopersim]

Sweet! Nice one, glad it's done the trick

[leeandzed]

My 335d is going to the indy on Monday to hopefully get the stats checked out, as my DPF light has come on AGAIN! Even after having it cleaned back in Nov, its become clogged again. So looking at this very informative forum about stats, i'm gonna be talking to the indy about checking all the stats. I've also noticed recently that the temp inside the car isnt as good as it was a few mths back, maybe related? Keeping everything crossed because if this doesnt fix it then its going to the main steeler for a PX !!!

[coopersim]

Originally Posted by leeandzed

I've also noticed recently that the temp inside the car isnt as good as it was a few mths back, maybe related? *snip*

Someone mentioned that following this the car warms up inside much faster.

[philmots]

Had mine done tonight.

Straight up to temp super quick. Will keep an eye on MPG but looks to be 3/4 better at the minute.

Happy.

[Dan-danGT]

Did my egr stat first and it made very little difference, from my normal 80c coolant temp. Changed main stat last night and drove 2 miles home with it already warm and it hit 92c and stayed there. Happy days. Thermostat was a pain to do, because the bolts into the manifold for egr cooler was tight to the point of snapping. So I wiggles it around the cooler hopefully mpg will be better aswell

[utkunoa]

Hello friends I am new in here from turkey !

I think I have a problem with my cooling system. I open the coolant temp from hidden menu. It show 92-94 centigrat in normal use, when I use with high boost its increase to 115 !. I change the EGR termostat. Main termostat. and water pump. But problem is still continue. Is my DPF is full ? car do regen everytime to clean the DPF ? Please help me

Thanks
Utku