I have read numerous posts about idle problems but none with the exact symptoms I am having. Car runs good until it warms up. Once warm it has idled low (around 500 RPM's) since I got the car. It has recently started bucking periodically and almost stalling while at stop. RPM always drops but never rises past 500 RPM's once warm. Car also idles terrrible at around 750 RPM's.
It seems that most people had some luck replacing temp. coolant sensor. Shouild I start with this? Any suggestions would be much appreciated.
1994 1.6 DOHC
thanks
Poor Idle and hesitation around 750 RPM
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Typhoonk
- Regular Member
- Posts: 1138
- Joined: December 31st, 2002, 2:01 am
- Location: Bowmanville
- Contact:
I have been fighting this for a while. Much better now - but still does it once in a while.
1. I took off and cleaned throttle body, IAC, TPS and the full intake
2. Adjusted TPS and idle control
3. Added more grounding wires, tranny to body, engine to body, alternator to body, battery to body.
4. Added a capacitor to my sound system.
5. cleaned all grounding points for head lights, tail lights and any other factory grounds I could find.
6. Took alternator in to be tested
7. Took battery in to be tested (have a optima yellow top)
8. I added a volt meter in the car so I could watch the voltages
found out when it idles low or rough idle the voltage drops two to three volts. (so from 14.4v to 12.4v). So I am guessing something has a parasitic voltage drop in it. I am currently testing the DRL lighting system. I have disconnected it, and will see what happens (as the problem doesn't happen all the time).
Here's to getting all the info on this stupid mx-3 problem
Cheers
1. I took off and cleaned throttle body, IAC, TPS and the full intake
2. Adjusted TPS and idle control
3. Added more grounding wires, tranny to body, engine to body, alternator to body, battery to body.
4. Added a capacitor to my sound system.
5. cleaned all grounding points for head lights, tail lights and any other factory grounds I could find.
6. Took alternator in to be tested
7. Took battery in to be tested (have a optima yellow top)
8. I added a volt meter in the car so I could watch the voltages
found out when it idles low or rough idle the voltage drops two to three volts. (so from 14.4v to 12.4v). So I am guessing something has a parasitic voltage drop in it. I am currently testing the DRL lighting system. I have disconnected it, and will see what happens (as the problem doesn't happen all the time).
Here's to getting all the info on this stupid mx-3 problem
Cheers-------------------------------------------------------
Got to sell one of my cars to cover the bills
2002 Mazda Protege 5 - Manual, Blue colour fully loaded
PM for info
Got to sell one of my cars to cover the bills
2002 Mazda Protege 5 - Manual, Blue colour fully loaded
PM for info
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Typhoonk
- Regular Member
- Posts: 1138
- Joined: December 31st, 2002, 2:01 am
- Location: Bowmanville
- Contact:
Well cars running great no voltage drops and my sub sounds better!!
all I did was unplug the DRL lighting relay in the passenger kick panel (the bigger one towards the front of the car).
My theory is when it heats up, it create's a huge amperage draw!!!
Probably why my headlights kept blowing after two months!!!
Just got to remember to turn on my lights manually now
all I did was unplug the DRL lighting relay in the passenger kick panel (the bigger one towards the front of the car).
My theory is when it heats up, it create's a huge amperage draw!!!
Probably why my headlights kept blowing after two months!!!
Just got to remember to turn on my lights manually now
-------------------------------------------------------
Got to sell one of my cars to cover the bills
2002 Mazda Protege 5 - Manual, Blue colour fully loaded
PM for info
Got to sell one of my cars to cover the bills
2002 Mazda Protege 5 - Manual, Blue colour fully loaded
PM for info
cFanjoy:
If other proposed solutions do not work, it could be your Engine Coolant Temperature (ECT) Sensor. FYI - If I recall correctly, it is on page F-162 of the manual... The ECT is located by your distributor.
I'm raising this as a defective ECT can lead to intermittent low idle issues (almost to the point of stalling). This is particularly the case once the car warms up.
Good luck!
If other proposed solutions do not work, it could be your Engine Coolant Temperature (ECT) Sensor. FYI - If I recall correctly, it is on page F-162 of the manual... The ECT is located by your distributor.
I'm raising this as a defective ECT can lead to intermittent low idle issues (almost to the point of stalling). This is particularly the case once the car warms up.
Good luck!
Thanks for all of the detailed suggestions so far. The weather has been bad and I haven't had a lot of time to investigate. I am going to put in a new ECT as soon as I can get one.
Also I want to test my TPS but am pretty useless with a multmeter. Can anyone tell me how to check continuity?
I also have a question about an air filter that is right in engine bay. I know it will suck in hot air and probably lose HP, but does this mean you should have better gas mileage?
Also I want to test my TPS but am pretty useless with a multmeter. Can anyone tell me how to check continuity?
I also have a question about an air filter that is right in engine bay. I know it will suck in hot air and probably lose HP, but does this mean you should have better gas mileage?