MX-3.com

http://www.mx-3.com/phpBB3/viewtopic.php?f=15&t=72056

Hi Guys,

I have always had an idle prob with my car. (car history in url above) It would be steady at 1300, untill you press in the clutch, then it would drop to 700. (have tried to reset it using the normal methods described in this forum)

Problems just started today are:

Car revs itself when in idle. (as if you where doing it with your own foot) Push in the clutch and it comes down and stays steady.

Engine overheating badly and no hot air from blow heater. Maybe head gasket im thinking?

Any help would be really appreciated.

Thanks guys
Andy

Most of that sounds normal to me like when you start the car it will rev up until it's warm and when you put in the clutch it does normally drop the idle a bit. With the heater it could be that the heater core is clogged I would try and take off the two hoses that go to it under the hood and get a garden hose and try and blow it out that way.

Hope this helped you out some.

Did you check simple things as coolant level?

sounds like a vacuum leak. look around the break booster.

What's your oil look like? Throwing any codes? There are easy ways of diagnosing head gaskets. A surging idle can also be caused by a TPS thats way out.

Sounds like your coolant is low as idle is controlled by coolant temperature sensor and if it is low you won't get heat from your heater and your engine will over heat. Sometimes even if the coolant looks fine you could have an air lock but this is normally rectified once the engine cools. Check your fluid level and ensure the system is primed by rapidly squeezing the upper large coolant hose. This will chase any air out of the system. Anyway Happy Saint Patties Day unless your Orange then drink the green beer anyway.

Hi Guys,

Thanks for your replies. Coolant is fine.

Could someone explain to me how to exactly to pull the codes from my car. I have tried but get nothing from it. I fear i am not doing it right as i am not a mechanic.

I do however have a good understanding of the mx3 as i have been refurbing this one from a non starter.

Thanks for your help fellas.

ANDY

No heat blowing means one of a few things.

missing w/p belt
plugged heater core/rad/something else
low coolant
H/G blown causing lots of air to be blown into the cooling system

andywilson24 wrote:Hi Guys,

Thanks for your replies. Coolant is fine.

Could someone explain to me how to exactly to pull the codes from my car. I have tried but get nothing from it. I fear i am not doing it right as i am not a mechanic.

I do however have a good understanding of the mx3 as i have been refurbing this one from a non starter.

Thanks for your help fellas.

ANDY

You need to use a code reader, yours is an OBD2 system. Either buy an interface and connect it to a laptop or go to a garage and pay to have the codes pulled. Something like this. http://obd2pros.com/

ok.

Found a wee vacuum hose out just under the throttle body. (that hopefully will take care of idle probs.)

No blockages in rad. Thermo workin ok.

Think it may be water pump? Even though it was brand new 1 year ago. Is there a way i can tell? How do i flush my engine block to see if there is blockage it?

cheers guys

Leave the rad cap off and once the engine heats up you should see the coolant flow.

Additionally, once the engine starts to warm up and coolant should be flowing the lower rad hose should get hot from the coolant.

Idle sorted. It was the vacuum pipe that had slipped off.

I have now flushed everything, including heater core. I now have heat in the car.

Prob now is that the fan is not coming on. So i guess it may be the fan assembly faulty or would i be right in saying that it may be a collant temp sensor? (does that initiate the fan to come on?) btw where is it?

Thanks guys

Is the car ready to overheat and the fan still does not come on? I assume you're talking about the fan on the radiator. Coolant temp sensor, fan relay or the fan itself could be a problem. Look at the manuals section E2. The online manuals are accessed on the left side of the index page and here.

I had a problem with radiator fan in my car and found the connector to the fan was corroded and making a bad connection. A simple check of the fan is to bring 12VDC directly to the fan and see if it runs. The manual will detail the correct wires to use for testing. Use a 12VDC power supply or just run some wire from your battery to the fan.

im having the same problems with my car with over heating i was having the idle problem to till i wraped a plastic bag around the stock acrodian like intake hose to stop the leaks through all the cracks in it. i was wondering if it was a blown hg wouldnt my oil look bad from mixing with the coolant. just a thought from my past experience. I intend to perform a coolant flush soon to see if this will fix my cooling problem if anyone else could be informative on the subject please feal free to help out. thanks