Coolant temp sensor or iac problem

[bomdoutscort]

Well my car drove fine yesterday on my way to school. It was about 85 out when i left. I know its low on coolant but just been too busy to refill it and i really havent been driving my car much lately. So today i go out to my car to drive it and its a lot cooler of a day 50's in the morning. So i get in and start it and it starts idling irraticly up and down and almost stalling. Sometimes stalling. My wideband reading is 10.0 the whole time its idling. So i start driving and when i'm not in boost its like its flooding out the motor and sputtering. Until my coolant gets to the middle of the gauge/normal operating temps my idle wont stay constant and read 14.8. My question is do you think its the coolant temp sensor causing this crazy richness and idle surging? Or is it the iac causing the idle to do that and not hold during cold start. I filled the car up with coolant and it still does it.

[bomdoutscort]

Well thanks for the help CP...Anyway i think it was an ecu problem. It was acting up again today doing exactly what was described and i was on the highway in 5th. I had to stay in boost or it would sputter. So i would tap the gas pedal down hard and let off so it would go into boost. Well i was in 5th and pressed it down hard and i saw the boost climbing up and it went to 12 and i let off. So i wanted to try it again thinking if it is reading 10.0 on the wideband then maybe it wont cut out. So i hit probably 15 or 16 psi and it cut out. After the cut out the car ran like it normally would. No more flooding or anything.

[Zexcort]

I 'm having a problem similar to yours but just on start up...it's drivin me insane

[bomdoutscort]

The car is still having problems. Well the idle surging is still there. Only sometimes though. So i went and got a new coolant temp sensor and changed the thermostat. Put both in and still having problems with the car puttering at cruise. In boost the car runs decent. I'm going to try to change the plugs soon. My biggest problem is the car is eating gas like a suv. I drive 10-15 miles one way to school and back home. The car was above a quarter when i left this morning. I get home and its almost at E. I really need this fixed soon. This is my only real transportation right now. Oh also my wideband isn't working so i can't see if its still running rich.

[bomdoutscort]

Also could a bad battery cause this? I lift the hood and hear the battery hissing. I've been having battery problems before all this happened. The battery can start the car but it might have too much of a voltage drop to power the car when its running.

[roymacavoy]

could be all that you have stated unfortunately! You can check the batterty with a volt meter, or run it to advanced and they will check it for free. Have you cleaned your TB and all that? Plugs good? Fuel filter, or even fuel pump? Maybe just some bad gas.
It sounds weird! This may be a dumb question but hows the exhaust flow? Maybe your choking the engine?

[bomdoutscort]

Thanks for all the points. I changed the plugs today and i think that i have a short at the air flow meter. Also the tps had a loose wire.

[Mazda_Powered]

the rich issue could be the coolant temp sensor and stalling, but the idle issue if it is too high would be the iac.

a bad battery would not cause this issue.

what type of blow off valve do you have? is it leaking at idle?

[bomdoutscort]

I think either the rich was from the tps because i would unplug it and plug it back in and my wideband(which started working again) went up to 14.5 at idle finally but soon went back to 10. I was under the hood with the car on and it was surging at idle again so i pushed down on the afm wires and it shut off

[bomdoutscort]

Well the afm didn't like to be flat so i turned it a little and now it runs fine again.