Sunfire with ICE in air duct!

[mike_needs_help]

Hi all, I am discouraged, I am frustrated !
I need you to try your best to solve this problem.

Very simple:
My car: Sunfire 2004 automatic ecotec motor.

Problem: I live in Quebec, Canada. My car stalls whenever it's a humid and cold weather . It's been two years now.

- The 2 repair guys told me they could not understand WHY theres ice forming in the air conduct , ice that melts and then produces humidity and water going in my motor. They could not find WHY this could happen even calling GM pontiac.

- Spent enough money on "testing" .

I really need to hear from you guys, even if you don't know how to solve it, I'm open to any contacts you may have to solve this. Its a pain in ... to stall all of the time on a cold weather here... Please help.

Here's a pic, I have removed the air conduct and snapped a pix to show you that even in cool weather at night, some water forms in it.

Important fact. No check engine lights on, and my air filter is totally DRY so I know it's not comming from there.



I really am exhausted, its been 2 years now that I almost can't drive in the winter season.

[Airjer_]

Hows this for a theory. PCV valve? If the valve isn't working than the condensation from the motor would work its way throught the breather hose and into the air intake?

Do you make a lot of short trips. Start it drive 10-15 miles and shut it off?

[KiwiBacon]

Is your air intake in a warm or cold location?

[MagicRat]

This is a variation on carburetor 'icing' which has been a problem on some carbureted vehicles for decades.

The ice is coming from moisture in the air. There is no extra water going into the engine at all.
What is happening is when the air passes through the intake system, there is an air pressure drop as per Bernouli's principle.

The pressure drop allows the moisture in the air to fall out of suspension and freeze at the point of low pressure, which forms ice in the intake manifold.

Many cars use some method of heating the intake manifold and/or air going into the engine to avoid this problem.

Many cars use a 'heat riser' tube. This is a duct which allows warmer air to be drawn from around the exhaust manifold and sucked into the intake manifold, thus preventing ice from forming. Usually the ducts are thermally controlled so they only draw this warm air when the air temp and/or engine is cold.

Many cars use engine coolant circulated through the intake manifold, through their own passages. The coolant does not come in contact with the incoming air; it just warms up the intake manifold, so ice does not form. If your engine has such passages, it is possible they are blocked by debris or were not assembled or manufactured properly.

I am not sure which, if any, manifold heating system your uses.
However, I am sure there is something not working properly on your car as all GM cars tend to work well in cold weather.

This post is just a suggestion for where to look. IMO if your mechanic does not understand the principles of intake manifold icing then he is not a good mechanic.
I can understand a mechanic from a warm climate not knowing, but Quebec??? He should know. If he doesn't, get another mechanic.

[Airjer_]

I think your on to something magic. I totally spaced the coolant passages around the throttle body! I guess I was thinking along the lines of there was more water than usual?

[mike_needs_help]

Hi guys, thanks ! Well just to make sure, I post another answer I got on another website and you tell me what you think about it? thanks!
I'm gonna take a few min make sure I can explain it well in french to our french mechanics here.

----------------------
HI there in Nanook-country!
I think Malcolm -or is it Clementine the cat? is on to something.

To get rid of the condensation in the pipe I would locate LOWEST point on level ground ,drill a small hole ,press in the collarpart of poprivet from inside and press on plastic or rubber-tube on to the collar from outside..

I love 5-dime solutions to a $500 problems!

To preheat inlet I would buy a good lenght of brake-tube,the semi-soft coppertype. find the lowest point of inlet-hose to rad.
curl the coppertube tight around the inlet-hose a good 10 rounds
then draw the two ends paralell up to the inlet drill 2 holes in the inlet-pipe.make another nice curl (like a coil of spring) inside the inlet-pipe. Fill up the brake-line with antifreeze screw them together one male one female fitting..
Soon after start up the inlet-pipe to rad should be hot enough so antifreeze in brakepipe will travel up due to ziphon-effect cooled off by air it will sink down-replaced by hot stuff coming up...

Reg.d trade-name:CLC-CN (Closed Loop Circuit for Cold Nanooks)

-I have a MitsuBITCH with same problem-This One problem solved but lots of other problems with it -I've had it with this sorry excuse of a car so one of these days I will put an ad in the paper inviting frustrated M'Bitch owners to a KILL A 'BITCH BATCH outside the main entrance of Norwegian M'Bitch importer.
-Hope you get it going soon-and Remember! Don't eat the yellow snow!! -R.

[mike_needs_help]

Originally Posted by KiwiBacon

Is your air intake in a warm or cold location?

Hum i dont know KIWI. Here's a pix of my car so maybe it can be seen?

[Airjer_]

Here's what concerns me about the second picture. The air intake system gets warmed up through the heat of the engine. Anytime cold air enters this area there is a chance for more condensation (the broken vacuum line). Any opening in the air intake could cause this.

I remeber a Saturn L Service that the throttle was sticking on after driving for a little while in cooler weather. After confirming the problem wiyh a test drive I found the the airtube was left loose around the throtle body. When I removed it there was plenty of ice built up. After further conversation with the customer he just had it in for an oil change and it started right after. The airtube has to be removed to check the filter and thats when it was left loose. Tightening up the clamp to keep the cold air from getting in took car of it.