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Hey guys i have a 92 Mx-3 V6, and when i do a cold start, "I live in calgary Alberta" so i mean like -20 , my car idles at about 2700 RPM until it reaches the ideal engine temperture.... is this normal??

Have you tried pulling CEL codes? (Check Engine Light) codes.. easy to do.. place a jumper wire between TEN & GND on your diagnostic box. Its located near the firewall on your drivers side of the engine bay. When you open the lid you will see a diagram which will tell you which ports are TEN & GND. A paperclip will work fine to jump with. After you have the jumper in place.. get into your car and turn the key to the "Run" position. No need to start the car. Count any flashes you see coming from your CEL. Then you can reference the code in the online shop manual and see what the code means. If you dont get any codes.. well at least you know that your electronics are all functioning fine.. might need to do a bit of clean up on your throttle body.. but in any case.. start with the CEL codes. Cheers

Tunes67

Does your idle stay at 2700 until you reach running temp? Or does it step down gradually as temp rises? Your car starting out idling high and than stepping down as the engine warms up is completely normal. The bottom half of the TB has something called the IAC (idle air controler) which circulates coolant through it and based upon that temp reading will adjust your idle accordingly. My car on cold starts usualy is about about 2000 rpms but the temp here never gets near that cold. 2700 seems high but than again -20 is really freaking cold.

Nate

1992blazeredgs wrote:but than again -20 is really freaking cold.

Nate

lol try your mx3 in over -30, last year we got over -50, do you plug your car in at all? i regularily do now and once ive started it it drops down to normal ideling rpms

alright ill try the CEL codes when it worms up... and yea the rpms gradually decend as the engine worms up.. and I DONT HAVE A BLOCK HEATER car was imported from vancouver where they dont install them factory..

haha i bought my car frmo a friend .. and the car somehow came from edmonton.. so lol i dunno... atleast its ain great condition with no rust so im happy about dat

dude that is normal for your car. if you want check your coolant but it should be fine. our cars rev up to that rpm then gradually drop while the temp rises. aslong as it stops around 700 rpms when it is warmed up.

1992blazeredgs wrote:Does your idle stay at 2700 until you reach running temp? Or does it step down gradually as temp rises? Your car starting out idling high and than stepping down as the engine warms up is completely normal. The bottom half of the TB has something called the IAC (idle air controler) which circulates coolant through it and based upon that temp reading will adjust your idle accordingly. My car on cold starts usualy is about about 2000 rpms but the temp here never gets near that cold. 2700 seems high but than again -20 is really freaking cold.
Nate

Exactly!! Although the testing of the ISC is to be done at 20C (with an anticipated resistance reading of between 10.7 ohms and 12.3 ohms) the coolant thermosensor (green one) also works in conjunction with this. It's rated to give the ECU data from readings from -40C to +80C. It would be assumable that it could go to 2700rpm on initial start-up but should gradually step down as previously mentioned. One word of recommendation - to garner extra life from the battery and to psuedo guarantee a longer running happier engine, I would strongly recommend the installation of at least a block heater. As we all know the most critical harshness placed on the engine is on cold moring start-ups. That said, we (us northerners) should do what's necessary to ensure engine longevity. FWIW, I continue to plug my Protege in every night when it's going to be anything less than 0 celcius. I plan to keep that car for some time and for the pennies it cost in electricity, it's well worth it. Not to mention how toasty the car gets within a minute or 2 on the way to work rather than getting toasty as I turn into the parking lot at work. As an added sidenote, not letting the engine reach it's full operating temp and sustaining it for an adequate period of time and by repeating this daily for winter can lead to some nasty issues with the engine oil. The constant short runs and lack of lengthy engine temp runnings may lead to a build up of condensation in the engine (oil) which will turn it to a milky colour. This will have serious detrimental effects.

I've had the same cold start high idle situation with my MX3 and I live in the midwest where it doesn't get as cold. After reading your post I decided that, that high of an idle just can't be normal. I decided to clean my throttle body and see if that makes a difference. IT DID. I used almost a whole can of cleaner. I removed the air intake into the throttle body and the outside of the throttle plate was fairly clean, I opened the plate and the backside and the inside of the throttle body was caked with dirt and oil. I used a deposible toothbrush to assist in the cleaning. When you go to restart it, it will be hard to start and will blow large amounts of smoke for about 5-10 minutes, but when mine cleared up it ran stronger and responded quicker. The following morning the idle was high with the cold start , but only about 16k which I think is very normal and it idled down much quicker. Good Luck