headache....

[Benz300]

Once again my lovely w124 has developed a situatoin even the dealer has trouble diagnosing. so where else but this forum to seek a solution ! :-D
It started last week or so. basically while driving I started to get a headache that I couldn't describe the root cause of. so i opened up the window a little and it felt better. closed the window after a while and the headache was back. so after a little while I figured since the heat is on let me try to shut that off. and there the headache was gone again.
I've figured this much out. as long as the car's vents are being used with fresh air either on heat or cold settings (without a/c) just on the EC mode, something from the vents compartment travels inside the car causing a headache. And to prove that it's not just me I had some friends of mine sit in the car and they complained about the headache as well.
I can't smell any fuel fumes so I'm ruling out fuel leaks. But any idea as to what else could cause this ? I took the car to the dealer, and they were just dumbfounded.
My research tells me that headache is usually caused by carbon monoxide.. question is where to look for such leaks that are only entering the car when the vents are working.... thanks for the help in advance and I really need some advice since I don't want to drive in such cold without heat...

[kerry]

Put a carbon monoxide detector in the car to confirm its presence.

[Benz300]

thanks for the reply Kerry,
I've seen CO detectors for home operating on 110V but where do I find the detectors to be used inside the car ? will they be battery operated or run off the car's 12V system ?

[kerry]

There are battery operated ones (I have one in my motorhome). I bought it at the local hardwarew store. However, I believe that are pieces of paper with a chemical dot on them that changes color in the presence of carbon monoxide.

[waltermitty]

If you are near an airport, swing by the pilot shop where you may find passive units as well as plug ins (to cig lighter). Hmmm, i'll bet a boat shop might have them as well.

[Hatterasguy]

A marine store will have or can get 12V CO detectors. Try West Marine. www.westmarine.com

[xp190]

You can get one of those eliminator things that converts 12V to 110V and use a regular plug in type CO detector, if I remember correctly, those detectors are quite pricey.

xp

[Benz300]

Thanks guys for the replies. I went to home depot and got a CO detector that works with 3 AA batteries. it was $49 but hey atleast i'll rule this possiblity out. I'll try to put that in the car and leave the car running for a while. I'll keep you guys posted with the results.
Happy new year to all of you.

[Benz300]

besides putting the CO detector inside the car, should i put it against the engine while running ? will the CO detect leaks like that ? I'm trying to figure out where the fresh air in the vents is sucked in from, because that's where the CO would be coming in from to begin with.
is the exhaust pipe from the engine to the back the only place where CO is present ? any other areas that I should check with the detector ?
thanks.

[sbourg]

CO is likely the only thing you will encounter with no smell and producing a headache. It is also likely not coming through the vent, but through a floorboard, trunk, etc rust-out or missing drain plug. The vent system in flow through simply helps evacuate the fumes before your symptoms appear. I don't know how likely an exhaust leak into the coolant might be, and if so how it could leak out inside without a significant coolant spray, but if all other sources are eliminated... Check all places where entry could occur with a smoke tester.

Steve

[Norm in FL]

Benz300, You may have a leak in your heater core. The anti-freeze from the heater core may be giving you the headache.Norm in FL

[Benz300]

Norm,
thanks for the reply. as much as I would like to be a tech-wannabe, I'm still in the learning phase :-D
could you be kind enough to elaborate on the heater core. what it is, where it's located and how I can check it's proper functionality.
thanks again.

[Norm in FL]

Benz300, Are you loosing any coolant from the radiator? If it is a small leak it could take some time to see it. The heater core is in the A/C duct system . It is a major project to replace it. You should be able to have the cooling sys. cked. for leaks at a dealer or radiator shop. Norm in FL

[kerry]

I can usually smell even minor leaks in a heater core quite easily. Hot antifreeze has a distinctive odor. If the odor is not present, I would suspect another source for the problem.

[dtf]

Here's a long shot - how long have you owned the car? Maybe there is mold somewhere in the duct system causing the headaches. It has been known to cause headaches in households. Maybe there was some water damage from the PO that you don't know about.