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Discussion Starter #1
I've noted some strange behavior lately that I'd appreciate some opinions on. There are two issues.

The car is a 2003 GLS Tip AWM, 107K. A K&N filter was just recently installed. There have been no CELs during these scenarios.


Issue 1

The first scenario has occurred twice in the past two weeks (and never before). Both instances of this scenario were on mornings when the air temp was about 40*F and also exhibited the problem behavior in the second scenario detailed below as well.

After starting the car, the interior turn signal indicators (both dash light and audible click) do not function, although all signal indicators on the exterior do flash properly. Additionally, the dash "Break" indicator light and computer "Handbrake On" message intermittently flash. Sometimes you can drive for some time without the car thinking the handbrake is on and other times it is a constant irritant. The climate fan (standard unit, not Climatronic) does not operate either. The stereo operates normally.

During both occasions, the above behavior ceased as soon as I turned off the ignition and restarted the car. Subsequent restarts could not reproduce the behavior.


Issue 2

The second scenario may have always been happening, and I just didn't notice it until recently. When starting the car on mornings when the tempurature is just below 40*F, the turnover and start is sluggish (though it's never failed to start). The engine initially sounds quite rough, though it steadies out after a few moments and idles at 800 RPM.

This is different than "normal" warmup when the temperature is above 40*F or under 30*F. In those cases, the car will start right up and idle at 1200 RPM to warm up, eventually slowing down to an 800 RPM idle after a few minutes.
 

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I would call issue 2 normal. If you observe, the idling happens at an RPM slightly higher than what it settles down to usually (800 RPM) after your Secondary Air Induction system turns off on regular (non cold) mornings.

Issue 1 concerns me. Check to see if the driver side carpet is wet (at least damp). If it is, open hood, remove the cover over battery/ECU/Brake reservoir. If required, remove battery and check to see if the drain hole under the battery is clogged. If it is, remove debris and clear passage.

Water if cannot drain properly, ends up getting into the cabin and soaking up the carpet. The Convenience Control Module CCM sits under the driver carpet in the footwell. It may have taken some of that water in, causing intermittent shorting.

Others will add to this.
 

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issue 2: i observe the same as you. on cold starts, the engine is "noisy" which settles down after achiving some temperature.

issue 1: i just don't believe that you'r k&n filter is causing that. it sounds like impending electronics failure...
 

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musk said:
Issue 1 The first scenario has occurred twice in the past two weeks (and never before). Both instances of this scenario were on mornings when the air temp was about 40*F and also exhibited the problem behavior in the second scenario detailed below as well.

After starting the car, the interior turn signal indicators (both dash light and audible click) do not function, although all signal indicators on the exterior do flash properly. Additionally, the dash "Break" indicator light and computer "Handbrake On" message intermittently flash. Sometimes you can drive for some time without the car thinking the handbrake is on and other times it is a constant irritant. The climate fan (standard unit, not Climatronic) does not operate either. The stereo operates normally.
During both occasions, the above behavior ceased as soon as I turned off the ignition and restarted the car. Subsequent restarts could not reproduce the behavior.
Issue 2 The second scenario may have always been happening, and I just didn't notice it until recently. When starting the car on mornings when the tempurature is just below 40*F, the turnover and start is sluggish (though it's never failed to start). The engine initially sounds quite rough, though it steadies out after a few moments and idles at 800 RPM.
This is different than "normal" warmup when the temperature is above 40*F or under 30*F. In those cases, the car will start right up and idle at 1200 RPM to warm up, eventually slowing down to an 800 RPM idle after a few minutes.
IMO, this sounds like it could be a low voltage issue at startup causing electronic malfunctions which go away after a little charging - your battery could be on its way out, or the battery cable attachments may be dirty.
 

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Discussion Starter #5
The front carpets are completely dry and there has been no dampness inside the cabin at all.

DaveW, I like your theory about the battery. I removed the battery cover a couple weeks ago while installing the K&N and noted no corrosion. I will double-check the battery connections and compartment for signs of a problem. If the problem persists, I'll see about replacing the battery.

WRT the idle issue, I had previously thought the car bypassed it's 1200 RPM warmup at any temp below 40*F, but this morning it fired right up at 30*. So it seems that between 30-something and 40*F are what produces the 800 RPM-only warmup. I'll keep an eye on this and report if there are any changes.

Thanks for the ideas, folks.
 

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musk said:
WRT the idle issue, I had previously thought the car bypassed it's 1200 RPM warmup at any temp below 40*F, but this morning it fired right up at 30*. So it seems that between 30-something and 40*F are what produces the 800 RPM-only warmup. I'll keep an eye on this and report if there are any changes.
This may not relate, but when i had a 1995 Ford Escort, it would sometimes seem to be on the wrong map for startup around 50F (it would not start immediately at 50F even though it was fine above 55F and below 45F). I wonder if your car has a similar situation.
 

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musk said:
Issue 2

The second scenario may have always been happening, and I just didn't notice it until recently. When starting the car on mornings when the tempurature is just below 40*F, the turnover and start is sluggish (though it's never failed to start). The engine initially sounds quite rough, though it steadies out after a few moments and idles at 800 RPM.

This is different than "normal" warmup when the temperature is above 40*F or under 30*F. In those cases, the car will start right up and idle at 1200 RPM to warm up, eventually slowing down to an 800 RPM idle after a few minutes.
I have the same EXACT problem as you. It does it about 75% of the time if the temp is below 40ºF. It's been a pretty mild winter, so I haven't really noticed what she does below 30ºF or so. I have been trying to figure out what the hell is going, but to no avail.

Does anyone know if a coolant temp sensor would cause this? I'm asking because the problem seemed to start after my oil cooler busted. Mixed oil into the coolant system. All repaired, but if the coolant system wasn't flushed out good enough and oil residue still remained on the sensor, could this cause that?

musk: sorry for the slight hijack, but I figured it could help out with your situation too. :thumbup:
 

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Another Battery Vote...

Be sure to clean both Battery Post Connections and the Battery Ground Connection too. Your Battery may be on it's way out as well. A car w/over 100K Miles has had enough thermal cycles to build up some oxidation on Electrical Connections...clean them before replacing components.

None of this costs you any money...always investigate the least expensive repairs first. General housekeeping like cleaning electrical connections is always the first step in determining where the real gremlim lies.

Good luck!
 

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The first thing that popped into my head was the battery. But are you saying that the car starts completely normally when its above 40 or under 30? If so I would guess theres probably something else going on. I would think the problem would be as bad or worse the colder it got. But I could be wrong so I'd still check the battery. And the idea of the coolant temp sensor is another good idea. If the battery checks out fine I guess I looked there next. Can you diagnose a failing temp sensor with a vag com? Maybe someone else can be of more help and let us know what you find out about the battery.
 

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Discussion Starter #11
V-MANN said:
The first thing that popped into my head was the battery. But are you saying that the car starts completely normally when its above 40 or under 30?
Yes, that's correct so far. It hasn't been a very cold winter and so I've had a lack of days below 30*F to reference. Until a few day ago when it was 30* out and the engine fired right up to idle at 1200 RPM, I would have said the problem was anything <40*F.

Today the engine actually idled at 950 RPM. Temp reading was 37*F.
 

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musk said:
I've noted some strange behavior lately that I'd appreciate some opinions on. There are two issues.

The car is a 2003 GLS Tip AWM, 107K. A K&N filter was just recently installed. There have been no CELs during these scenarios.


Issue 2

The second scenario may have always been happening, and I just didn't notice it until recently. When starting the car on mornings when the tempurature is just below 40*F, the turnover and start is sluggish (though it's never failed to start). The engine initially sounds quite rough, though it steadies out after a few moments and idles at 800 RPM.

This is different than "normal" warmup when the temperature is above 40*F or under 30*F. In those cases, the car will start right up and idle at 1200 RPM to warm up, eventually slowing down to an 800 RPM idle after a few minutes.

so this happens to everyone & is normal????

i notice that on my b5 recently too... when is under 35 it starts w/rpm not passing 800rpm when is above 39-40 degree out side temp the car goes over 1k-1200rpm for warm up.. so this is normal????
 

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First thing is make sure your battery is okay because sluggish turnover usually indicates bad battery or battery connections. Go to a battery place and have them check the battery out. It's usually free or get a voltmeter and measure your battery voltage after driving for a while to fully charge the battery (with car off no lower than about 12.5 volts) and when it's running (about 14 volts for a good alternator). If you want to try a load test, turn your key on but do not start the car and then turn on your headlights. Monitor the voltage for about 5 minutes. If the battery is bad the initial voltage will fall quite rapidly to below 12 volts.
 

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I've gotten the same behavior, Musk. On my W8 it runs real rough on damp, cold mornings (25-45*F) for about 10-15 secs, then stabilizes. Dealer won't even check it.

I got my battery replaced and belts tightened, problem still happens.

Did someone say a coolant temp sens.?
 
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