Before beginning - full disclosure... I am a woman in my 30s with no real car repair experience. However, I'm usually able to pick up on things quickly, and can follow directions well. I've got my Haynes ready at my fingertips.
Please describe the overheating. Temperature gauge in the "red," coolant boiling out on the ground, steam from engine, etcetera. Was any steam or white smoke ever coming from the tailpipe behind the car ?
I don't know if it technically overheated - it never boiled over. Temperature gauge was in the red, and the "check gauge" alert on the dash was lit. No steam or smoke from engine or tailpipe.
Please describe the situation in which it occured. Were you moving down the road, idling, etcetera ?
We had been driving for about 30 minutes in city traffic - had just come through the Holland Tunnel (i.e., slow moving). I had noticed a few days earlier that the air conditioning was not cool when idling.
Does the vehicle have a "low coolant" warning in addition to high temperature indication ? Did this alert you ?
No "low coolant" warning.
Do you know how the shop diagnosed the problem ? They should have been able to test the fan/motor quite easily.
I'm not sure how they diagnosed it (although, see my description below) - it was part of a "coolant system evaluation" at Pep Boys.
The reason I'm asking so many questions is that this condition can be difficult to diagnose. I'd hate for you to put all this stuff on and still have an overheat problem. Sometimes even low coolant level can cause all of your symtoms and one needs to determine why it was low. Some 03-04 Ions with the 2.2L engine have been found to have porous cylinder heads, for example.
I think the coolant level was fine - the receipt says the coolant system eval included: "Visual inspection of underhood cooling system, components. Block test. If block test passes, inspection will continue with pressure test of radiator cap, addition of coolant dye and visual inspection for leaks under pressure." They also charged me for the coolant dye, so that tells me they did the entire inspection. Their recommendation was: complete coolant exchange, remove & replace engine coolant temp sensor, remove & replace cooling fan relay, and remove & replace cooling fan &/or motor."
I just wanted to make sure that it all actually needed to be replaced, so I wanted to test it step by step. If it's just the relay, I'd like to just do that first (because it's easiest)!
Do you have air conditioning ? Do you know where the electric radiator cooling fan is ? If you start the car and run it for a few seconds and turn on the air conditioning (set to "cold" and A/C / heaterblower fan "on") does the radiator fan run ? Don't put your fingers down there. Fans bite !
Since the A/C is not cooling when idling, I think that probably means the fan isn't engaging. Getting ready to test this now, though.
You'll not want to operate this car until the problem is resolved. Any actual overheating has the potential of damaging the car's engine and/or cooling system. Do you know which engine you have ?
I think the engine is a 4-1998 2.0L DOHC (just got that from the receipt printout).
Thanks for any additional help!