Recently my cooling fan comes on sometimes right as I start the car (cold) or a couple minutes after. It stays on and will turn off when I shut the car off and doesn't stay on after the car is off like most people have experienced. Also about the same time this started happening my car start kind of rough most times, hot or cold, and sometimes it starts and shuts off. By starts hard I mean starts and has a rough idle between 500-800rpm for a couple seconds and then settles to normal. Anyone experience this before? Coolant temp sensor possibly? I have no CEL though.

 

What year, model, and miles would help. How long have you had the car? Any mods or work done lately? You have not given us much to work with.

 

2007 R56 non-s, 92k miles. Has a DDMWorks intake, magnaflow muffler, those have been done for a while though. I have had the car since December with no issues. I changed plugs today, thought I would start there with the starting issue, plugs were pretty bad and appeared to be originals or at least they were OEMs. Problem is still there though. Sorry for lack of information I usually give it.

 

Do you have a scanner? If so is the car throwing codes?

 

No codes and no check engine light

 

If it was an S there is a laundry list of things.

It seems odd that this just started happening, I wouldn't think that dirty fuel injectors would make a sudden problem. I think that the plugs are supposed to go 100k before changing, but it is a good start doing what you did.

Any leaks in the coolant system that have been repaired lately, or done any maintenance? I'm just wondering if there is an air pocket in the coolant system that would make the thermostat read inaccurately. Coolant level is fine? Look for residual coolant on top of the transmission (just to the right of the engine).

There is a bleeder on top of the thermostat, but it seems odd that it would suddenly have issues unless there is a leak or you had maintenance done.

Unfortunately, you are probably due for a new thermostat and water pump, they both have a history of leaking.

Mike

 

Have monitored coolant levels as well as look for coolant leaks and nothing seems to be suspect. I have done no cooling maintenance to the car since I have owned it, have not even removed the overflow lid. It has started to get really warm here recently, but shouldn't explain on cold starts. Issue seems to be less often past 2 days oddly enough.

 

Some symptoms similar to what I had with my MINI. Cooling fan would run much longer than normal before shutting off. Engine cranked longer than normal before starting. Then run rough for a few seconds.

Coolant /thermostat sensor was the diagnosis. This was in Sept 2012 and I had a little over 60K miles at the time. Fairly big job (replace water pump) which I had done by an independent shop. While they had the front end of the engine disassembled. I also had them replace the serpentine belt, spark plugs and coolant.

Seems like I read somewhere in these forums (a couple of years ago?) that there is a (relay/fuze?) that can also be a culprit which is an easy fix.

 

Did yours throw a check engine light or temperature light? What was the cost of getting all of that done?

 

+ 1 on checking that sensor, if the coolant is low the senor does not get hot. But if the sensor is bad and the coolant is up to the proper level. Then the Fan runs all the time.

Water Temperature Sensor 13627535068

http://www.ecstuning.com/Search/SiteSearch/13627535068/



To check the relay also :

https://www.northamericanmotoring.co...g-off-car.html

 

Hm so there appears to be no fool proof way to test the relay. What else needs to come apart to replace the sensor? Thinking of ordering the r3 and r4 sensors just to be sure.

 

The theromstat housing sensor can be done from the top. Held in by a clip/.





The relays are listed ( white green )

 

No, I never got a check engine or temperature light. It didn’t strand me either. But I just knew that something wasn’t right.

Work was done at an independent repair shop.

Parts and labor were about $590 for the thermostat issue. Since it was in the shop anyway I told them, before they even started, to do following additional maintenance and inspections. So, another $350 for serpentine belt. Then $200 for spark plug replacement. Add another $80 for LOF. And finally about $225 for a valve inspection.

When this work was done (about 3 years ago) was a lot of forum discussion going on about valve carbon buildup. So I had them remove the intake manifold and inspect valves. Mine were clean. Turns out that valve carbon buildup is not typically an issue with non-S engines. But things were still being sorted out then and I wanted to be SURE since the car was there being repaired anyway. I have been pretty religious in using only top tier 91 octane gasoline.

My car travels extensively between Wyoming and Las Vegas. I take advantage of my time in Vegas to have maintenance done. If I had been in Wyoming (where my tools are) I could have at least done the spark plugs and LOF myself. But I was in Vegas and could not disregard the possibility of being stranded on some lonely stretch of highway 100’s of miles from knowledgeable service.

Subtract $150 from the above as a discount for being a SCMC member.

This has been the only significant repair ever needed in 8 years of ownership. 86K miles now. I just had new brake pads installed. So, overall, the car has been quite trouble free. And, amazingly, I’m still on my original battery and it tests fine. Car uses no oil, everything works and is running great.

By the way. Tomorrow (15th) is final day to register for AMVIV 11 which takes place in Vegas 28-31 May see www.amviv.com

 

No oil usage, incredible, probably explains why you have had almost zero issues with your engine! My engines it really good condition considering I burn 1/2 quart every 800 - 1000 miles, had my valves walnut blasted and it wasn't really that bad compared to others. My compression readings are that of a new engine very near 170 PSI.

 

Time for an update, my car was about 5 months into the oil, about like 5500 miles or so, But with the time and 5500 miles I decided to change it. It appeared to be about 1 maybe 1.5 quarts low, dip stick sucks so I cannot read it well, and now the car starts and idles fine just as it should. However I have noticed that if I start the car with the A/C on and then turn the A/C off the fan stays on, if I don't ever have the A/C on it comes on normally but doesn't go off, I am going to pull relays tomorrow if I get time, I am leaning towards stuck relay?

 

$200 for spark plugs?! Dang they took you on that one. Why was the serpentine belt $350?! Doesn't seem too bad to do by looking at it?

 

Update, so I checked my fuse box the other day and it appears I am missing R4?

 

Yep stage two fan ?

 

Sorry for the delayed response, but I believe it has a 2 stage fan? How would I know?

 

Today was warm and I noticed my fan coming on more often. Cold weather you might not notice it on even after driving long distance. The more you know.

 

If my fan is running, I shut car off and it goes off, I start car and it doesn't come on for probably 10-15 minutes. Once it comes on the only way it goes off is turning off the car.

 

How it's supposed to work is whether your engine is on or off when the ECU reads a predetermined coolant temp the fan comes on. The same thing is true if under the hood temperatures gets hot on say 85+F. Once it was 100+ degrees ambient and I stop by my house, came our 10 minutes later and started my engine, holy moly my fan was extremely LOUD. Intake air temps was 140F!

 

My car has sat in 65 degree temps for 5 hours, start it up fan instantly kicks on. In mid 70s I drove 65 miles on highway at 65mph and got to my destination fan was still on, every stop light on the way, fan on. I wish these had temp gauges.

 

Bump

 

The fan will stay on indefinitely if you are using the AC.