Found that stain on the engine. Those are under the plastic upper intake manifold (just in front of the firewall).
Will be doing the following later today.
Power steering flush
Replace engine air filter
Replace cabin air filter
Replace engine oil and engine oil filter
Other issues that need resolution. AC/Heater
Front AC vents blows but if temperature outside is cold, then it will blow cold; if temperature is hot/warm, then it will blow hot/warm.
Rear AC vents blows cold
The air flow blowing out from those vents (front and rear) can be adjusted from low to high. So I know the blower probably works fine. Could it be some or one of the actuators stuck? Or is it something more expensive to fix?
Automatic Transmission
Pan drop or flush? It is still on its original automatic transmission fluid.
EDIT: Do front wheel drive vehicles like my CX-9 have transfer case and rear differential fluid needing changing?
Thank you. I will add the Check PCV System on the list. Since it is already at 163,000 miles, then I would probably need to replace the spark plugs and ignition coils while checking the PCV System.
The HVAC
Front Ventilation (Both front driver and passenger vents)
When I set the climate control to cool/cold air, it will not blow any cool/cold air. If I set it to recirculate air in the cabin, then it will recirculate ambient air temperature from the cabin. If I set it to use the air from outside, then the temperature will depend on whatever the outside temperature is; if outside temperature is hot, then it will blow hot air; if outside temperature is cold, then it will blow cold air (I tested it last night since it is cooler at night, cool air came out, similar temperature from the air outside).
When I set the climate control to warm/hot air, it will blow warm/hot air.
Rear/Middle Seats Ventilation (Center console)
When Dual Climate is ON and rear controls set to Cool/Cold, then it will blow cool/cold air.
When the Dual Climate is ON and rear controls set to Warm/Hot, then it will blow warm/hot air.
I don’t know if one of the vent door actuators is broken or stuck. The blower seems to be fine as I can adjust the amount of air (like in an electric fan-low, medium, high fan settings) it generates. Later today, I will have HVAC lines checked and probably evacuate and refill with a new one.
There are other issues but the following are low priority.
Front driver side door can only be locked using the physical key.
The sun visor hinge is worn out/flimsy
The driver side rear/middle passenger window cannot be controlled from the switch on the front driver seat.
It’s a good idea to check the pcv system as part of routine maintenance, but those stains look to be pretty normal for a 2008. Suggest to not lose any sleep about the engine stains. If you don’t like their appearance, you can always clean them off with an engine degreaser product.
Replacing he spark plugs at 163 k miles makes sense, probably beyond the suggested replacement interval already. But does your maintenance schedule require the coils be replaced as part of routine maintenance? If not, as long as engine is running smoothly, might be better to hold off on that.
As far as the AC problem, does your car use a separate AC evaporator for the rear system?
Does it blow cold air ok from at the rear of the vehicle when rear controls are set to cold? But you never get cold air at the front no matter how the controls are set? If so, my guess, that would more likely be a problem with the hvac control system rather than the front evaporator itself. I’m guessing since there’s just one compressor, the refrigerant paths are all shared among front & rear. If the rear produces cold air, the front most likely has access to the same refrigerant supply, so if there’s no cold air from the front, most likely one or more of the hvac doors in that area are not moving into the correct orientation, and blocking the cold air flow. An alternate theory, it could be something is preventing the refrigerant from flowing into the front evaporator, expansion valve possibly, assuming there’s an expansion valve for each evaporator in that set up.
Mechanics mentioned about compressor, AC condenser, and suction hose needed to be replaced. Something about a leak. They declined to do a recharge. I got quoted around $2,000 with compressor as re-manufactured part.
Noise like when a metal plate is in contact with another surface - front passenger side
The noise changes or louder when I was driving on a curvy road with bends. Each bend will create a louder noise.
I had mechanics check it before I had them check the AC. Two separate occasions-one for that noise and the other is for the AC. Sames ones from the same shop, who checked the AC.
I described it to them. I was told there is nothing wrong with the brakes. I asked if there is something wrong with the wheel bearing. One of the mechanics told me he was not told that anything was wrong on the wheel bearing.
Driving the CX-9 seems to be okay aside from that noise. It does not go left or right during driving on a straight line.
I have not done the rotation test nor the shake test on the front passenger tire.
On humps and dips, a sound like a spring being compressed is coming from the front driver dash.
How can I know if the front struts needs replacing? Or if it just needs some lubrication? Does the struts needs lubrication?
I need to replace all 4 tires soon, feathered.
I am thinking whether I replace the tires now or wait until the noise issues are resolved.
I am thinking of putting the AC system on the lowest priority. I’ll just do the old style of driving-windows rolled down during hot/warm days plus that small electric fan on the dash (or somewhere on the front).
