Question about 2007 Chevrolet Cobalt Coupe

2 Answers

The coolant temp will sometimes go blank (---) and when it does the AC stops working. When the temp reads. Number the AC kicks back on. My check engine light is also on sometimes. I took it to autozone who told me that it said the coolant temp is too low or something like that. Which I can only assume is because it's not reading any temp at all.

Posted by on

Ad

2 Answers

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Vice President:

    An expert whose answer got voted for 100 times.

  • Expert
  • 320 Answers

If your temp gauge is going blank several things can cause this. one is a bad wiring connection on the sending unit itself. could be corrosion on the connectors. these types of sending units work like a thermistat they do go bad. but id be looking for a loose ground. since this circuit is grounded to the body you could ground the system by using a set of jumper cables. use one side to ground the battery to the body and the other side to ground the motor to the body and see if it still happens.
a large amount of electrical issues are created by faulty grounds. i usually start by disconnecting the harness from the sending unit and inspecting it,if its not damaged. i would then reground the systems

Posted on Aug 31, 2010

Ad
  • Level 1:

    An expert who has achieved level 1.

    New Friend:

    An expert that has 1 follower.

  • Contributor
  • 1 Answer

Not really a answer to the question more info on the problem I have a 08 cobalt with the same problem I replaced the coolant temp sensor and pigtail to it and still have the same problem I found out that if you disconnect the battery or reset the computer with a scanner it will work for some time never more then a day tho. It sounds to me like its a ecm problem.

Posted on Dec 21, 2016

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi there,
Save hours of searching online or wasting money on unnecessary repairs by talking to a 6YA Expert who can help you resolve this issue over the phone in a minute or two.

Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.

Here's a link to this great service

Good luck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

2 Answers

Radiator fans not coming on. replaced thermostat and cooling sensor


Hi Bill, is the engine actually getting hot enough for the fans to come on? if the engine does have overheating problem (but you say the temp gauge reads normal) then i would check the operation of the engine temp switch, there are two, one for the gauge and one for the fans.

Oct 15, 2016 | 2006 Ford Escape

1 Answer

A/C cooling fans, A/C only cools when car is in motion????


Cooling fans are most likely not coming on. I believe that vehicle has two fans..side by side, one closer to passenger side is ac fan..should come on when you cut ac on. I would check coolant level some sensors will not read temp correctly unless submerged in coolant...fans should kick on when car reaches somewhere around 185 to 205....should be a plastic fuse box under hood that houses fan relay...also should be identical relays that run headlights or something else..you can swap relaysaround to see if the relay has gone bad. If fans aren't coming on or one of the two is..turn the one not coming on by hand to see if fan motor has frozen up

Sep 18, 2015 | 2005 Lexus RX330

1 Answer

I have a 97 Cadillac eldorado and although the temp gage doesn't read hot, it sometimes floats a little over the 1/2 way mark. seems really hot. You can smell coolant and the top big radiator hose doesn't...


If the temp gauge periodically rises higher than normal and then falls back to normal, you probably need to change the thermostat as it may be sticking shut and then popping open. It's a good time to change some hoses, coolant and check the belts if they've been on the car for awhile.

Sep 09, 2013 | Cars & Trucks

2 Answers

Coolant fans not working can overheats when driving slow


did you get any obd codes ?? well there is a possible the power relay or ac relay is not working.

Sep 24, 2012 | 1999 Pontiac Grand Am GT

1 Answer

2008 ENGINE HOT / AC TURNED OFF ALARM


There are a number of things that can cause the problem you are having. The most common is actually a faulty thermostat. If it sticks closed it can cause the engine to overheat (no brainer). What some people miss is a thermostat that sticks open or opens too early. This (the open thermostat) is most likely what's causing your problem. The engine doesn't heat up properly and the computer doesn't trust the readings it's getting so it goes into a failsafe mode. It turns on the light to warn you, turns off the gauge (because it doesn't trust it, if you will) turns off the AC to reduce tempuratures, and kicks the fans on. At some point (usually not the first time) it will set a code P0128 (coolant temp below thermostat regulating temp).
Here's what I recommend:
Check that the engine's cooling system is full and free of air pockets. I know you mentioned that the fluids are full but this is critical and worth double checking.
Check (when cold) to be sure the thermostat does not allow flow.
Allow the engine to heat up to make sure that it begins to flow.
Check trouble codes. Autozone will do this for free. Remember that it could take some time to set this or other codes but it's worth checking now. Please ignore them if they tell you the check engine light has to be on to check for codes and ask them to humor you. Tell them that some @$$hole told you to do so :-)
Get back to us with your findings. There is more to come. We may need to check for other issues like a faulty ECT (engine coolant temp) sensor, wiring/connection problems, computer problems, etc. but the other things should be checked first.

Feb 07, 2018 | Chevrolet Impala Cars & Trucks

1 Answer

The cooling fan on my 2001 Mustang runs constantly. Even when the engine is cold. The temperature gauge reads normal. The engine has 39,000 miles. What is the problem?


low engine coolant ,coolant temp. switch for the fans,fan relay shorted closed.and possibly a computer.check for codes,coolant level in radiator when cold,remove relay for fan and see if the fan stops. check to see if the ac is on or if the heater ac switch is in defrost position. ac will be on and coolant fan is commanded on also.i hope this will help.

Oct 27, 2009 | 1995 Ford Taurus

2 Answers

3.1 L Grand Prix-cooling fan won't kick on, new fan motor-all fuses OK-temp when driving cools OK with AC fan on. Where are the relays ?


probably not a relay,check the coolant temp sensor to make sue its reading ok,if its misreading it will not tell the computer to turn the fan on

Oct 14, 2009 | 1994 Pontiac Grand Am

1 Answer

My 1993 Cadillac STS , keeps overheaing , why ?


clogged radiator. over flow tank cracked or to full. thermostat not opening at 190 degress.fans not kicking on. check relays. also check coolant temp sensor and temp sending unit. unplugg the coolant temp sensor it should kick on the fans instantly and illuminate the service engin soon light. do u have a digital cluster? if it is saying stop engin temp replace the temp sending unit. located on the back of the rear valve cover were the spark pluggs are closest to the driver side area

Sep 20, 2009 | 1993 Cadillac DeVille

1 Answer

Overheading 99 deville


The fans don't kick in until around 225 degrees.

As for the overheating, Check for coolant flow at the Purge line,this is a common problem on the Northstar.
There is a small diameter hose coming from near the top of the coolant tank,this is the purge line.
With the engine idling,pull the purge line from the tank,if there is no coolant flow from this small hose,it is blocked and this will cause overheating.If the hose is clear, check for blockage at the nipple on the tank.

Regarding the misfiring, have you changed your spark plug cables?

VERY IMPORTANT....only use AC Delco spark plugs and wires.

Spark plugs ....AC Delco part number 41950

Plug wires....AC Delco part number 748Q

Ignition problems are common if you use anything other than the above OEM parts.

Sep 14, 2009 | 1999 Cadillac DeVille

1 Answer

2006 HHR my a/c stopped working and the engine coolant temp guage reads blank at the same time suddenly


check to see if the cooling fan is working and if is not then ac pressure gets to high and clutch shuts down. you may have bad temp sensor or relay.

Aug 22, 2009 | 2008 Chevrolet Hhr

Not finding what you are looking for?
2007 Chevrolet Cobalt Coupe Logo

786 people viewed this question

Ask a Question

Usually answered in minutes!

Top Chevrolet Experts

yadayada
yadayada

Level 3 Expert

79865 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22326 Answers

Ronny Bennett Sr.
Ronny Bennett Sr.

Level 3 Expert

6927 Answers

Are you a Chevrolet Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...