Idle increases in a traffic jam

Len Lewin · Post by **Len Lewin** » March 17th, 2005, 10:32 am

I have been stuck in a traffic jam 3 times now. Stop and creep, stop and creep. Each time has been for over 1/2 hour. After about 20 minutes, the idle started picking up. Twice it reached over 1500 RPM before the traffic started moving again. I though it was related to hot weather, but the last time this happened it was below zero. I thought the car might be overheating but the engine temperature looked normal. Any ideas what may be causing this?

Chasing_Size · Post by **Chasing_Size** » March 17th, 2005, 12:46 pm

check your timing or your idle air control valve

snellgrove · Post by **snellgrove** » March 17th, 2005, 12:59 pm

nowt to do with the cooling fan cutting in? wouldn't seem right for it to jump that high tho

I've been in traffic and with the air-con on, highest I've ever seen is 1100rpm, which I aint too worried about.. altho that is high for an MX-3 lol, they tend to sit around 600/700!

jschrauwen · Post by **jschrauwen** » March 17th, 2005, 1:11 pm

It doesn't take much for the engine temp to get hot. Although your gauge may be barely past the "normal point", when it does get quite hot your fan will kick in. As well, the ECU will initiate a higher idle so as to keep the coolant circulating fast enough so it can be cooled, yes even if it's only 0 'c. 1500 rpm is not unheard of, I believe. Other considerations, when was the last time the cooling system was completely flushed, when was the last time the thermostat was changed / checked for serviceability. Even regular (quality) oil changes enhances the cooling abilities of the engine. In other words, when it starts to get out of a healthy state of tune, things start to happen. This is pretty generic stuff, for the info you provided. Telling us a very descriptive story with specific details can prove advantageous in assisting you with your mechanical woes. FWIW

Len Lewin · Post by **Len Lewin** » March 17th, 2005, 3:30 pm

Thanks for the tips on what to check for. From the replies, some of you are suspecting the engine is trying to cool itself down.

"Normal" operating temperature is about 3/4 of the way to hot. Is this too high? Also I have a bra on the front of the car. I will remove it and see if this makes a difference next time I'm stuck in traffic. I do not have air con.

I don't know if this is related, but if I turn on the wipers or roll down the window while I'm stopped, the idling plunges briefly.

The engine was flushed at 70,000 km (3 years ago) when I had the timing belt changed. A new water pump was installed at this time. Also had a tuneup at this time. The car now has 130,000 km. '93 MX3 GS.

Tunes67 · Post by **Tunes67** » March 17th, 2005, 3:44 pm

Len Lewin Wrote:

"Normal" operating temperature is about 3/4 of the way to hot.

Granted my car is an RS.. but I think the general concensus here will agree that this is too high. My gauge runs "Normal" at a bit less than 1/2 way up the gauge. This would indicate that your thermostat is opening at a much higher temperature than its supposed to be. Cheap easy fix.. about 15 minutes and done for less than $20 easy.

Tunes67

mxmaz · Post by **mxmaz** » March 17th, 2005, 3:44 pm

Len Lewin wrote:"Normal" operating temperature is about 3/4 of the way to hot. Is this too high? .

Is that the way it has always been? I guess it depends on your perception looking at the temp guage but mine when warmed up is at i'd say 3/5's.

jschrauwen · Post by **jschrauwen** » March 17th, 2005, 4:19 pm

Depending RS or GS on another thread, the general concensus was that the temp gauge will be either at, slightly below or slightly above the halfway mark if coolant quality and thermostat integrity are verified. "3 years / 60k km ago" - Ya your past due for a flush and as the rest said replace the thermostat. While your at it why not get a colder thermostat so the it will open sooner and stay open longer for improved cooling. Since you're living in the big city of Edmon-chuck (jk) and if the majority of your driving is city than more frequent than factory directed coolant maintenance habits should be adopted, IMO. If you've been driving for a considerable period of time with your temp gauge reading that high I would seriously do an inspection of other engine components because of the excessive heat that has been present. Check all of the hoses and rad for starters. It appears that your car may only get the attention it needs when something goes wrong. This site does support an online manual which would be extremely advantageous in adopting a better preventative maintenance perspective. IMO Hope this helps.

Steeb · Post by **Steeb** » March 18th, 2005, 4:05 am

your oil level may be low