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KGB
12-11-2004, 11:11 PM
My '97 540i had a thermostat replaced by the local dealership this week at the same time I changed the oil. They had to bleed the coolant line after that, but, obviously poured too much coolant into the tank, because the dipstick is all the way up with the cold engine. On that model, as well as few others, it's supposed to be flat with the plug hole.

I started to notice now that the temperature gauge needle is slightly past the middle point, but I can't say for sure if it was precisely in the middle before the thermostat was replaced.

My guess is that there's nothing serious to worry about, just want to confirm with the rest of the folks in this forum that my engine temperature is normal which means that the cooling system is working properly.

I went into OBC Test mode, under "Test-07" it showed 110 degrees Celcius on a hot engine, and after 5 minutes or so it was 105 degrees. Is that temperature normal for a 8-cylinder engine? Thanks.

Fern
12-13-2004, 10:12 PM
Hi KGB,

Welcome to the e39 board.

Have you noticed any coolane residue around the expansion tank cap?

If not, then I suspect things are o.k. You might however have a slight air pocket which is causing the coolant to show an improper reading.

As for the temperature it is very important that all leaks be sealed so that the system can operate at full pressure. The engine computer is programmed to keep the coolant temp at about 108C at "most" times (there are exceptions) and the only way it can maintain that temp (above the boiling point) is if the pressure can be maintained - system fully sealed.

I have a question...
Have you noticed any leaks from an elbow located at the top of the driver's side of the rad?

This is a common weak point in the rad and is a $2.00 part, (yes $2). I had mine replaced when the coolant was flushed..

BTW, why was your thermostat replaced? Overheating? Who was the dealer that did the replacement?

Cheers,

Fern

Predator_e36
12-13-2004, 10:30 PM
ur temp should fine

KGB
02-02-2005, 03:44 PM
Guys, sorry for a long delay with the reply to this post... The rad was replaced early January just for $100 thanks to the dealer where I had bought the car. The elbow connecting to the expansion snake hose was all broken inside, and it virtually crushed in my fingers when I pulled it out. I tried to put it back in(or what left of it) and used some epoxy but it didn't last long, obviously, because of the pressure in the cooling system. I guess other plastic parts of the radiator were becoming fragile. Like someone said these plastic radiators need to be swapped regularly just like Wal-Mart bulbs :) Finally, I took a car to the dealer to show the failing rad. They saw the leak from the elbow and suggested I replace the whole thing to be on the safe side. I should've also replaced the expansion tank though it still looks ok. The coolant level dipstick broke last night when I checked the level after adding Red Line Water Wetter to it. It's plasticky and the lower part which contacted with the coolant all the time became very soft eventually. I can live without it for now, but should definitely change the expansion tank.

The dealer who replaced my thermostat is in Ottawa - "Otto's BMW" on Hunt Club Rd. I'm not 100% sure if it really needed replacement, but when they said that the diagnostics told them that the thermostat sensor didn't respond, I bought it and said: "go for it...".


For 540i owners - how do you folks like this car overall? I've had 530iA w/Sports package 2001(lease) until recently and find the 530iA to be way peppier and quicker than my 540i '97 with standard. The 540i feels heavier and not as quick in acceleration-response, it drives more like a caddy, than a bimmer. Is it common or there's something wrong with my car, should I check the powertrain/engine? Would like to hear opinions of others. Thanks!

///Greco540
02-02-2005, 04:13 PM
Well the peppiness of the line for any E39 auto is due to the 3.15 final drive ratio compared to 6 speed 2.81 being used, trust me though once moving the 530 would be bus lengths behind any 540. Personally I've yet to drive any 530 that feels as strong as my 540. I would suggest that the next time you visit a dealer ahve them clear the adaptations in the DME and then drive it like you stole it for a week. This should allow the car to learn your driving patterns and adjust fuel/timing maps. If the car was driven by a 60 yr old and then you get it and drive like a 60 yr old, it will drive like a 60yr old. If you venture out to Toronto, Fern, Quack or Rush can give you a ride in theirs and you can judge for yourself, or if you make it out to Montreal I'd be happy to give you a ride in mine.

I'd check to see when the cats were changed, if they weren't try and get into your dealer for the Federal emission warranty of 8 yrs/160K Km catalytic replacement. Then clean your ICV, get rid of the CDV (most likely the culprit of your sluggishness), and check for a bad CPS.

ICV = Idle Control Valve, rough idle
CDV = Clutch Delay Valve, slows engagement of clutch regardless of how fast of the pedal you get.
CPS = Cam Poisiton Sensor, will usually through a fault if bad.

KGB
02-02-2005, 09:10 PM
///Greco540, thanks for invitation, I'd be glad to have a ride in yours someday I take a trip to Montreal. My wife and I just went to Mascouche area north of Montreal last Saturday to pick up a Siamese kitten from a breeder(another passion - exotic cats). Waiting for a Cornish Rex as well.
Haven't had any chances to compare mine with other 540's, let alone 540's that have been modded. I am going to Elite BMW sometime soon to take a new 545i or 540i for a test drive, just to compare with mine. Usually they don't have it with standard to test.
Seen your site, the Blue Ice rocks!!! Looks great and sleek! Does the dash pixel problem occur on yours? I have it but still not too severe, thought it progresses slowly. I've seen the instructions how to fix it by oneself on the internet, will try it in the summer. Like the dark blue color too, mine is cosmos black. I've been seriously thinking about improving the suspension, liked the way the 530i w/sport was handling the corners.
About clearing the DME adaptation values. I should have tried this awhile ago as #1 thing, simply forgot it. I disconnected the battery for a couple of hours tonight after I came home to erase the memory from the chip. There should be no need to ask a mechanic for it, just disconnecting power from the car for some time will reset the values too. It did make a huge difference when I drove it tonight around the area, even with a slightly warm engine! Will try it out again tomorrow on the way to work(30min). How long does it take the DME to get new patterns for driving?
About CDV, I am not sure if I want to remove it or not. Some folks mentioned that the clutch became harder to push after that, cannot comment on that.
I commute to work on that car daily and usually the traffic is heavy between Ottawa and Hull, pushing a lot on the clutch saves me some workout:)
The ICV and MAF are a must too!!! I will inspect/clean them this weekend, probably, because I would need some daylight, I don't have a garage in this house(unfortunately) :(
The cats were replaced by the previous owner, I met him personally to ask a few questions before signing up for this baby, nice guy. Cats that are clogged are affecting the performance, that's for sure.
The cam sensor, I'm not sure if it has been replaced under warranty or not, good idea to check it next time I change the oil. My leased 530i had it replaced, since it gave me problems with starting the car occasionally.

///Greco540
02-02-2005, 11:51 PM
Damn that site(cardomain) is like 2 yrs old. I really need to get rid of it or update it. Thanks for the nice comments. I searched 8 months for a Biarritz Blue. I would have preferred a black interior but that would have been asking too much.

Usually once you disconnect the negative lead, if you turn on the headlights it should be enough to drain whatever is left in the system. A good 15 minutes is fine as well. I would say a good week until the adaptations are fully cycled. Every clear stretch of road, gun it!

My pixels come and go, more are going then coming back, but at least its consistent. Share the site for fixing this problem. I have no problems taking apart VDO clusters, I used to do that 10 years ago when I was manufacturing colored guages for VW's.

CDV? If you are a seasoned manual driver, trust me you want to remove it. It has no affect on the pressure of the clutch. All it does is moderate the rate of which the clutch engages. The only ill affect it has if you keep it on is show passengers that you can't drive a stick. The M5 doesn't have one. Proper bleeding of the system is required.

For steering feedback, yes there is a difference compared to your 530. The 540 uses a recirculating ball system, where the 528/530 is rack & pinion. It doesn't have an impact on actual ride quality and road holding, the 540 actually has higher trap speeds through slaloms. The only improvement is in steering feedback. Alot of people misinterpret this as a better suspension. Again the M5 has recirculating ball though because its the pinacle of driving machines it also has a servotronic system coupled with it. For suspension upgrades go for the Eibach sway bar kit. It offers the same diameter front bar as any other aftermarket maker but has the largest rear bar at 18mm. Dinan is 17mm and the M5 is 16.5mm. The 540 has a 15mm rear bar. A good strut/spring set will also help the ride become more sporty. I'm opting for the H&R/Bilstein Sport when the funds become available. Don't forget to check the front thrust arm bushings and rear ball joints. These usually go and can cause unwanted shimmying.

The CPS will undoubtedly light up the check engine light when it goes.

How about some pics of yours?

txminime
02-03-2005, 12:30 AM
Have you noticed any coolane residue around the expansion tank cap?


Fern,

What will cause the coolant to leak out and form residue around the expansion tank cap? The expansion tank was recently replaced, but there are some coolant residue around the cap. Dealer did a pressure test and reported no problems found...

FC

humanoid
02-03-2005, 01:27 PM
Fern,

What will cause the coolant to leak out and form residue around the expansion tank cap? The expansion tank was recently replaced, but there are some coolant residue around the cap. Dealer did a pressure test and reported no problems found...

FC

Adding to much coolant will cause this.

KGB
02-03-2005, 08:14 PM
My pixels come and go, more are going then coming back, but at least its consistent. Share the site for fixing this problem. I have no problems taking apart VDO clusters, I used to do that 10 years ago when I was manufacturing colored guages for VW's.
...
How about some pics of yours?

The site is http://www.vdorepair.com/ClusterRR/Remove.htm with instructions how to remove/install the instrument panel. You've seen it already maybe. On another forum, someone mentioned this site too and shared his experience of fixing the panel with a can of compressed air - most of the missing pixels came back, but not all of them. It's not the best fix for sure, complete disassembly and good cleaning with alcohol would do the trick. I wish I had a garage, spending an hour outside isn't much fun in such weather. I'm sure it's an easy job to do if you know how to use a screwdriver, most of the connectors(if not all of them) are not interchangeable, if two or more are the same, I would label them prior to disconnecting.

Sure, I'll take some pictures of the car after it's washed and will upload them on the net. Right now it's hard to tell what color it is because of the muddy roads here, though, I just washed it a few days ago.

About the CDV, did you trash the valve and connected the lines without it, or modified it by drilling a hole and reconnected again with it? Both ways should be fine, I guess.

///Greco540
02-04-2005, 09:50 AM
I've removed the cluster to replace bulbs and can tell you the connectors are not the same. I guess when I intall the rings on the cluster I'll take another look at it.

For the CDV I got mine done by the master himself. You can remove it completely as your without warranty. Ususally they replace the original one with a drilled out version. I would just remove it and reconnect the line directly.

Fern
02-09-2005, 04:48 PM
I've removed the cluster to replace bulbs and can tell you the connectors are not the same. I guess when I intall the rings on the cluster I'll take another look at it.

For the CDV I got mine done by the master himself. You can remove it completely as your without warranty. Ususally they replace the original one with a drilled out version. I would just remove it and reconnect the line directly.


If you are afraid of rethreading the line wrong and stipping it, I understand the e39 M5 clutch line is already moulded to accomodate proper threading angle as it does not have the CDV.