Low coolant, car immediately dies, wtf?

Robinc · 07-09-2009, 10:43 PM

Driving to work today and just like the title says, the low coolant light comes on and the car starts sputtering, and stalls out. Start it back up, rough idle, get it back to my garage and stalls out again. Call BMW, my SA tells me to call roadside asst. and tow it in. Figured i try adding some coolant and see if that changes anything, let the engine cool for a bit then added the coolant and start it back up, car is fine. Drove it to work 30 miles in 100 degree plus weather, not a single issue.

My question is: Is that normal for the light to come on and the car immediately die? I figured it would of given me a little more notice before dying on me. Anybody got any ideas as to what's going on or have an experience like this? My car does have 28,000 miles already and it was over triple digits today. Needless to say i'm taking her in on monday to see if there is a bigger problem.

jeremyc74 · 07-09-2009, 11:05 PM

Are you talking about the indicator that looks like the engine is half full?

If so, that's not the low coolant indicator that's coming on. It's the reduced power warning, and your HPFP is probably bad.

There's no good reason the car should die on a low coolant warning, especially the way you're describing. Break out the owners manual and make sure that's what you're seeing.

MOCKBA · 07-09-2009, 11:21 PM

I do not think that low coolant can issue such problem. I had low coolant warning in my Merc for 6 months until finally I decided to add some, and I didn't have any problems, no engine overheat or rough idle.
I also do not think that it is HPFP problem, since adding coolant returned the car to live.

Robinc · 07-09-2009, 11:49 PM

Quote:

Originally Posted by jeremyc74

Are you talking about the indicator that looks like the engine is half full?

If so, that's not the low coolant indicator that's coming on. It's the reduced power warning, and your HPFP is probably bad.

There's no good reason the car should die on a low coolant warning, especially the way you're describing. Break out the owners manual and make sure that's what you're seeing.

no, i'm positive it's the low coolant light, I have a tune and have had two half engine lights or limp modes from not letting the oil get up to temperature before getting on the high boost map.

Robinc · 07-09-2009, 11:51 PM

I've also had other cars that also had low coolant lights come on and continued to drive them for miles without a single issue, not this one however.

penny · 07-10-2009, 12:35 AM

I've had intermittent low coolant light for over a month and nothing happened. Finally decided to replenish it with water (since H20 is basically what's evaporating).

The light usually comes on after turning off the ignition. Never during a trip.

BrokenVert · 07-10-2009, 12:49 AM

When I was testing out my PS2 to see how I liked them I went into a very large parking lot and did a few skidpad and auto-x type things. My low coolant light came on (I guess with the tight turns I was starving the system?) And my car didn't die at all.

I don't think that your dealing with coolant.

kb2dhg · 07-10-2009, 08:08 AM

Here we go again, GET RID OF THESE ELECTRONIC COMPUTER devices and give us analog gauges! OH and while your at it GIVE ME MY FRIKEN OIL DIPSTICK BACK!
I HATE ELECTRONICS IN CARS! I AM PUTTING MY 128I up for sale! only 1,300 miles and I simply cannot stand the electronics!

The Cthulhu · 07-10-2009, 09:46 AM

It sounds like you fixed the problem. A few questions:

Did you note your temperature?
Would the ECU normally regulate overheating by going into limp mode?
What tune are you running?
Would your tune bypass any ECU feedbacks?
If you are running high boost, could your engine be overheating at points not monitored specifically by probes?

If you were running high boost and higher octane gas, I wonder if the engine management system can function correctly by monitoring coolant temperatures only (is that how it works?). From a non-linear heat flow perspective, it is possible that you could be running hot in areas undetected or uncompensated by the factory computer settings. BMW probably calibrated their cooling based on the OEM tune, so who knows what's going on.

One of the things Dinan said they did is increase the coolant pumping rate, something that some (or all) piggybacks don't do.

How much coolant needed to be added?

Evice · 07-10-2009, 10:42 AM

Quote:

Originally Posted by kb2dhg

Here we go again, GET RID OF THESE ELECTRONIC COMPUTER devices and give us analog gauges! OH and while your at it GIVE ME MY FRIKEN OIL DIPSTICK BACK!
I HATE ELECTRONICS IN CARS! I AM PUTTING MY 128I up for sale! only 1,300 miles and I simply cannot stand the electronics!

huh? wanna ride a bike?

JasonCSU · 07-10-2009, 11:17 AM

Quote:

Originally Posted by kb2dhg

Here we go again, GET RID OF THESE ELECTRONIC COMPUTER devices and give us analog gauges! OH and while your at it GIVE ME MY FRIKEN OIL DIPSTICK BACK!
I HATE ELECTRONICS IN CARS! I AM PUTTING MY 128I up for sale! only 1,300 miles and I simply cannot stand the electronics!

Good luck with that. I understand the gripe about the dipstick, but you are not going to see manufacturers reduce the number of electronics. Looks like you'll have to stick with older cars.

JimD · 07-10-2009, 12:30 PM

You could have a head gasket problem. You also mention a tune which I assume means more boost which can be hard on head gaskets. When this joint leaks, coolant can get into the cylinder and go out the exhaust. When you have water in a cylinder, it may not fire at all which would make the idle rough and could result in the engine dying. The chance of it leaking is probably greatest when the engine is not warmed up.

You might want to take your chip out or make it not obvious that your engine is modified before you go to the dealer. If it is a blown head gasket, increased boost could have contributed and they might not want to repair under warranty. It is also not something to go unresolved. If the engine gets enough water into the combustion chamber you can break things (water doesn't compress well). I hope this isn't what it is but it seems to fit your description.

Jim

imported_mega · 07-10-2009, 01:17 PM

the biggest problem with water is it'll get right past the piston rings and into the oil, water + oil = bad, and you dont even have a dipstick to check to see if it's milky

Robinc · 07-10-2009, 03:36 PM

Quote:

Originally Posted by The Cthulhu

It sounds like you fixed the problem. A few questions:

Did you note your temperature?
Would the ECU normally regulate overheating by going into limp mode?
What tune are you running?
Would your tune bypass any ECU feedbacks?
If you are running high boost, could your engine be overheating at points not monitored specifically by probes?

If you were running high boost and higher octane gas, I wonder if the engine management system can function correctly by monitoring coolant temperatures only (is that how it works?). From a non-linear heat flow perspective, it is possible that you could be running hot in areas undetected or uncompensated by the factory computer settings. BMW probably calibrated their cooling based on the OEM tune, so who knows what's going on.

One of the things Dinan said they did is increase the coolant pumping rate, something that some (or all) piggybacks don't do.

How much coolant needed to be added?

We don' have an engine temp gauge only oil temp, which mine never gets over 250.
I would think that yes, the ECU would go into limp mode, but I never got a half-engine light, just stalled.
I'm running procede v3 and no it doesn't bypass ecu feedback as far as i know.
The coolant was at the min i added enough to get it the max, not sure how much that was.

I was searching over on e90 and found a guy, without a tune, that had the exact same thing happen to him, turns out he had a bad water pump, not sure whats going on with me, all I know is since I topped her off, she's be running fine.

Needless to say I have removed my procede, and had a BMW shop do a code scan, there were no tuner codes present, but I also have a pre 03/08 build. Im off to the dealer later this week, and i'll see what they say

cagekicker · 07-10-2009, 04:49 PM

now that's strange!

joeo · 07-10-2009, 08:39 PM

If your coolant was low, there's either a leak, or coolant is getting into places it should not - like the combustion chamber. The cooling system is a closed system. Coolant doesn't evaporate away as it's completely closed (or supposed to be!).
I would get it checked out immediately.

-Joe
http://www.lovehorsepower.com

MOCKBA · 07-10-2009, 10:02 PM

It is closed system, however not completely. Your tires lose som pressure little by little, the same happens with coolant. However noticable loss of coolant can happen in 8-10 years.

AaronBernard · 12-13-2017, 11:08 AM

Bringing this back up in case anyone needs the info. I had the same experience as the OP but with more lights on the dash. (2007 335i).

I had just had the front brakes done by a shop and shortly there after the ABS failure lights came on the dash. I figured they bumped a wire and planned on taking it back to them to review.

Then I started getting the very rough idle when I would start the car. Mostly when the motor was cold and had been sitting (sounds like an injector right?).

I noticed the low coolant symbol pop up which was quickly replaced with the ABS fail symbols. What a mess.

I checked the coolant when the motor was cold and sure enough it was dry. Topped it off and now everything is working. No ABS lights on, car starts without rough idle and pulls hard off the line like it should.

I've done a little research and it seems with low coolant the engine temp sensor may be off and it will send the wrong fuel mixture info to the system causing it to run horrible on start.

I know its a closed system but driving everyday in the summer at 90+ degrees must have some impact on the coolant level...

Also to note, I pulled the codes after I got home and it showed a misfire. The symptoms on start + the code makes it look like something in the ignition like coils or injectors (which this car has had issues with) but thankfully those were not the case this time.

Winn.Nguyen · 12-16-2017, 02:19 AM

Expansion tank could have a small crack in it. Coolant slwoing leaking out.

Olgeezer1 · 01-01-2018, 04:22 PM

If the coolant was only at the MIN. mark, that shouldn't be enough to affect anything. Following an old tip to extend the life of the expansion tank, I run mine around the MIN. mark all the time with no problem and no increase in water temp.

07-09-2009, 10:43 PM	#1
Robinc Private First Class 6 Rep 114 Posts Drives: 135i Join Date: Apr 2008 Location: USA iTrader: (0)	Low coolant, car immediately dies, wtf? Driving to work today and just like the title says, the low coolant light comes on and the car starts sputtering, and stalls out. Start it back up, rough idle, get it back to my garage and stalls out again. Call BMW, my SA tells me to call roadside asst. and tow it in. Figured i try adding some coolant and see if that changes anything, let the engine cool for a bit then added the coolant and start it back up, car is fine. Drove it to work 30 miles in 100 degree plus weather, not a single issue. My question is: Is that normal for the light to come on and the car immediately die? I figured it would of given me a little more notice before dying on me. Anybody got any ideas as to what's going on or have an experience like this? My car does have 28,000 miles already and it was over triple digits today. Needless to say i'm taking her in on monday to see if there is a bigger problem.
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07-09-2009, 11:05 PM	#2
jeremyc74 Banned 76 Rep 5,970 Posts Drives: '08 135i Montego/Terra Join Date: Feb 2008 Location: Evansville, IN iTrader: (0)	Are you talking about the indicator that looks like the engine is half full? If so, that's not the low coolant indicator that's coming on. It's the reduced power warning, and your HPFP is probably bad. There's no good reason the car should die on a low coolant warning, especially the way you're describing. Break out the owners manual and make sure that's what you're seeing.
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07-09-2009, 11:21 PM	#3
MOCKBA Captain 54 Rep 870 Posts Drives: 135 convertible Join Date: Nov 2006 Location: SFBA iTrader: (0)	I do not think that low coolant can issue such problem. I had low coolant warning in my Merc for 6 months until finally I decided to add some, and I didn't have any problems, no engine overheat or rough idle. I also do not think that it is HPFP problem, since adding coolant returned the car to live. __________________ 535i/HUD Kamerton brings me true sound fidelity
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07-09-2009, 11:51 PM	#5
Robinc Private First Class 6 Rep 114 Posts Drives: 135i Join Date: Apr 2008 Location: USA iTrader: (0)	I've also had other cars that also had low coolant lights come on and continued to drive them for miles without a single issue, not this one however.
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07-10-2009, 12:35 AM	#6
penny Captain 43 Rep 829 Posts Drives: '08 135i (sold) Join Date: May 2008 Location: Las Colinas iTrader: (2)	I've had intermittent low coolant light for over a month and nothing happened. Finally decided to replenish it with water (since H20 is basically what's evaporating). The light usually comes on after turning off the ignition. Never during a trip. __________________ '08 135i.
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07-10-2009, 12:49 AM	#7
BrokenVert Resident Kerbalnaut 477 Rep 10,703 Posts Drives: Topless Brute/Hybrid Boogaloo Join Date: Apr 2009 Location: Fahrvergnügen/NY iTrader: (0)	When I was testing out my PS2 to see how I liked them I went into a very large parking lot and did a few skidpad and auto-x type things. My low coolant light came on (I guess with the tight turns I was starving the system?) And my car didn't die at all. I don't think that your dealing with coolant. __________________
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07-10-2009, 08:08 AM	#8
kb2dhg Private First Class 3 Rep 138 Posts Drives: 2009 128i Join Date: May 2009 Location: Yonkers NY iTrader: (0)	Here we go again, GET RID OF THESE ELECTRONIC COMPUTER devices and give us analog gauges! OH and while your at it GIVE ME MY FRIKEN OIL DIPSTICK BACK! I HATE ELECTRONICS IN CARS! I AM PUTTING MY 128I up for sale! only 1,300 miles and I simply cannot stand the electronics!
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07-10-2009, 09:46 AM	#9
The Cthulhu Banned 7 Rep 197 Posts Drives: N/A Join Date: Jun 2009 Location: N/A iTrader: (0)	It sounds like you fixed the problem. A few questions: Did you note your temperature? Would the ECU normally regulate overheating by going into limp mode? What tune are you running? Would your tune bypass any ECU feedbacks? If you are running high boost, could your engine be overheating at points not monitored specifically by probes? If you were running high boost and higher octane gas, I wonder if the engine management system can function correctly by monitoring coolant temperatures only (is that how it works?). From a non-linear heat flow perspective, it is possible that you could be running hot in areas undetected or uncompensated by the factory computer settings. BMW probably calibrated their cooling based on the OEM tune, so who knows what's going on. One of the things Dinan said they did is increase the coolant pumping rate, something that some (or all) piggybacks don't do. How much coolant needed to be added?
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07-10-2009, 12:30 PM	#12
JimD Brigadier General 368 Rep 3,547 Posts Drives: 128i convertible Join Date: Apr 2009 Location: Lexington, SC iTrader: (0)	You could have a head gasket problem. You also mention a tune which I assume means more boost which can be hard on head gaskets. When this joint leaks, coolant can get into the cylinder and go out the exhaust. When you have water in a cylinder, it may not fire at all which would make the idle rough and could result in the engine dying. The chance of it leaking is probably greatest when the engine is not warmed up. You might want to take your chip out or make it not obvious that your engine is modified before you go to the dealer. If it is a blown head gasket, increased boost could have contributed and they might not want to repair under warranty. It is also not something to go unresolved. If the engine gets enough water into the combustion chamber you can break things (water doesn't compress well). I hope this isn't what it is but it seems to fit your description. Jim __________________ 128i Convertible, MT, Alpine White, Black Top, Taupe Leatherette, Walnut, Sport Ordered 5/22/09, Completed 6/4/09, At Port 6/9/09, On the Georgia Highway 6/13/09, Ship Arrived Charleston 6/24/09 at 10pm, PCD 7/21/09
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07-10-2009, 01:17 PM	#13
imported_mega Colonel 122 Rep 2,199 Posts Drives: various bmw's Join Date: Jul 2007 Location: neverland iTrader: (0)	the biggest problem with water is it'll get right past the piston rings and into the oil, water + oil = bad, and you dont even have a dipstick to check to see if it's milky __________________ You only need two tools in life - WD-40 and Duct Tape. If it doesn't move and should, use the WD-40. If it shouldn't move and does, use the duct tape. Driving e82, e72, e85, R53 Gone but not forgotten.. 1974 2002, many various 3s.
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07-10-2009, 04:49 PM	#15
cagekicker Major 16 Rep 1,335 Posts Drives: '09 crimson red 135i Join Date: Nov 2008 Location: miami (vice city) fl. iTrader: (0)	now that's strange! __________________ 6MT/ Sport Package/ N54/ Asa wheels/ Eibach pro kit springs/ Active autowerke Exhaust/ 35% tint
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07-10-2009, 08:39 PM	#16
joeo Lieutenant 120 Rep 475 Posts Drives: 2009 Crimson Red 135i Join Date: Mar 2008 Location: Sterling, Va iTrader: (0) Garage List 2009 BMM 135i [9.50]	If your coolant was low, there's either a leak, or coolant is getting into places it should not - like the combustion chamber. The cooling system is a closed system. Coolant doesn't evaporate away as it's completely closed (or supposed to be!). I would get it checked out immediately. -Joe http://www.lovehorsepower.com
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07-10-2009, 10:02 PM	#17
MOCKBA Captain 54 Rep 870 Posts Drives: 135 convertible Join Date: Nov 2006 Location: SFBA iTrader: (0)	It is closed system, however not completely. Your tires lose som pressure little by little, the same happens with coolant. However noticable loss of coolant can happen in 8-10 years. __________________ 535i/HUD Kamerton brings me true sound fidelity
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12-13-2017, 11:08 AM	#18
AaronBernard Registered 1 Rep 4 Posts Drives: 335i Join Date: Nov 2007 Location: SoCal iTrader: (0)	Bringing this back up in case anyone needs the info. I had the same experience as the OP but with more lights on the dash. (2007 335i). I had just had the front brakes done by a shop and shortly there after the ABS failure lights came on the dash. I figured they bumped a wire and planned on taking it back to them to review. Then I started getting the very rough idle when I would start the car. Mostly when the motor was cold and had been sitting (sounds like an injector right?). I noticed the low coolant symbol pop up which was quickly replaced with the ABS fail symbols. What a mess. I checked the coolant when the motor was cold and sure enough it was dry. Topped it off and now everything is working. No ABS lights on, car starts without rough idle and pulls hard off the line like it should. I've done a little research and it seems with low coolant the engine temp sensor may be off and it will send the wrong fuel mixture info to the system causing it to run horrible on start. I know its a closed system but driving everyday in the summer at 90+ degrees must have some impact on the coolant level... Also to note, I pulled the codes after I got home and it showed a misfire. The symptoms on start + the code makes it look like something in the ignition like coils or injectors (which this car has had issues with) but thankfully those were not the case this time.
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12-16-2017, 02:19 AM	#19
Winn.Nguyen Private First Class 85 Rep 137 Posts Drives: BMW Join Date: Jan 2016 Location: Portland iTrader: (0)	Expansion tank could have a small crack in it. Coolant slwoing leaking out.
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01-01-2018, 04:22 PM	#20
Olgeezer1 Lieutenant 183 Rep 505 Posts Drives: 2010 128i 6MT Sport Pkg. 18" Join Date: Jul 2013 Location: Ottawa, Canada iTrader: (0) Garage List 2010 E82 128i N52 [0.00]	If the coolant was only at the MIN. mark, that shouldn't be enough to affect anything. Following an old tip to extend the life of the expansion tank, I run mine around the MIN. mark all the time with no problem and no increase in water temp.
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