CEL and low idle

[Birdman_7]

So my car warmed up usually idles at around 700, 600 if the fans turn on or whatever that does under the hood. If I rev really high and push the clutch in, and then don't release into gear for a while, the rpms will drop all the way and the car will die (sometimes). I used to just downshift through every gear to slow to a stop, now I just brake in any gear until about 1100 rpms, and then push the clutch in and brake the rest of the way.

Yesterday I got my first CEL, and also started using my AC cuz it's been frickin hot here! So when I drive my car warmed up with the ac on, it idles a little bit lower. I know this is usual. However, now when I come to a stop quite often the idle will drop when I push the clutch in and continue to drop all the way to 100 rpms and then bounces back to about 5 or 6. It just about dies, but then comes back. What the heck is going on?!

 

[jdwk]

Man, seems like everyone is having idle issues lately. It is not normal for your car to idle lower with the A/C on. Your car should idle between 650 and 750 rpms when warm without any accessories on. Extra load on the alternator will cause your idle jump to 800 rpm. This is usually caused by the cooling fan coming on, or the A/C being turned on along with the condenser fan.

If your idle drops when you turn on the A/C, something is definitely wrong. To me it sounds like an electrical problem. I had very similar symptoms when I decided to "clean up" my engine bay and redid some of the wiring.

Do you headlights dim significantly when your fans kick on? Do your rpms drop when you turn your lights on?

I am going to guess the CEL is a misfire. In which case, it is most likely a grounding problem. But if the CEL is a lean code, then you have probably have a vacuum leak.

If you want to own a 10 year old car, either because you love it or because it is all you can afford, you really need to buy a scan tool, especially if that 10 year old car is a MSP. A bluetooth ELM327 device is $25 tops now, and if you have a smartphone, the torque app is only $5.

 

[Birdman_7]

So I don't notice my headlights dimming, but I have hids so maybe the balasts are picking up that drop? When I start the car, I let it warm up, and turn the lights on, there is definitely a noticeable change in motor sound when I switch them on, but as far as I can tell it doesn't drop the Rpms at all..

 

[Birdman_7]

Okay so I finally cleared the code. The car scared the s*** outta me with the alarm when I reconnected the battery! Anyways the problem with the a/c is still there though. When I don't have the a/c on and it's really hot out, the car runs fine. I push the clutch in and the needle catches at around 1400 to 1500 and gradually lowers to about 1100, and when I come to a complete stop, it will hover around 800, down to 700 when the fans come on. When I have the a/c, it's really hot out, and the car is warmed up, the car will idle fine, maybe just a little bit worse, but when I push the clutch in to come to a stop, it never catches at that 14, 15. It just keeps dropping all the way down to literally 100 rpms, and just when I feel like the car's gonna stall, it bounces back to about 700. I'm shocked the car doesn't die, but I'm sure this can't be good.

 

[mazdarichie]

Join the club with the idle problem. Can't figure this out myself. I have tried about everything suggested on here and still runs terrible. So, Good luck and if you figure it out please post your solution.

 

[Pmpkinhead]

If you have over 80K on the original coils, it is a great place to start. I got a chinese pair delivered from @bay for $45. My idle and power issues were reduced. Note: I had to use the original MSP Stems that attach to the spark plug because the new ones were too short.

 

[jdwk]

Did you clear the code without having it read? It will be back. Might take a while but you can't solve problems permanently by just resetting the PCM.
Buy a scan tool. Then you can clear codes without having to reprogram your radio.

 

[Smitty1017]

Do you have a BOV? mine started acting similarly once I went dual valve. I still get a bit of turkey even with dual valve so i think my stock BPV is bad, so, I am going to get a Forge BPV..but yeah. If you are blowing off too much boost and holding the clutch and it dies or comes close, check the BPV, or the lines running to it. I am guessing it is that.

 

[Birdman_7]

So I haven't been driving my car for a while, it's hot here, and I've just been riding my bike. jdwk you were right the cel came back! But after a few weeks or so, it disappeared on it's own. I am planning on getting a scan tool soon now that I have an android phone. (There is no torque app available for iphones!)

My biggest problem is still my fuel economy! I still get anywhere from 12 to 15 mpgs.. I haven't messed with the SSAFC yet, I'm nervous! My only laptop with xp is really old and slow and freezes all the time.. I don't want to hurt my precious car..!

 

[Jo060]

Just a tidbit of info incase anyone was wondering. It's typically normal for your headlights to dim with 2001-2003 Proteges, the condition is the result of a slight delay in the alternator ramp up when the AC system is turned on (which includes the cooling fans). If this delay were not present the results would be an idle
speed dip, which Mazda feels would create higher customer dissatisfaction.

 

[jdwk]

I'll second that. I put in a fairly extensive grounding kit and there is still a very slight dim of the headlights as the fans kick on. This makes sense.

 

[JDMazdaFamilia]

My rpms would drop to about a hundred, cel would turn on, then rpm would jump back up just like your car. It was cause of a big vacuum leak

 

[Birdman_7]

yeah but mine only does it with the ac on and when i'm coming to a stop while driving slow..

 

[Spiced MSP]

My rpms would drop to about a hundred, cel would turn on, then rpm would jump back up just like your car. It was cause of a big vacuum leak

where was the vacuum leak

 

[chubhawk]

i have all these issues too haah idles low 500 rpms then drops to like 300 200 wants to die or if i drive and go neutral instead of downshifting rpms drop quickly then car dies hHA HA ALLREADY REMOVED EGR replaced sparkplugs seemed to help a small tad but all issues are still there keep us posted on ur results....

 

[chubhawk]

any updates on this

 

[pbarton14]

I had an very similar to yours and mine ended up being a huge vacuum leak . The egr was stuck open and I had to pry it shut again where the spring actually did its job. More than likely its something you looked over and didn't notice

 

[chubhawk]

I removed the egr took it all aprt cleaned it all out spring was easly pushed in and out maybee the solenoid went bad and leaves it open instead of closing it?

 

[bwlknsn91]

I removed the egr took it all aprt cleaned it all out spring was easly pushed in and out maybee the solenoid went bad and leaves it open instead of closing it?

Still having troubles?

 

[mazdarichie]

Good luck with figuring this out. I have the same problem. Almost for a year now. Changed the EGR, IAC, Both o2's, spark plug wires, Fuel injectors, Seafoamed it, cleaned the MAF sensor. And no cracks in the duct work at all. No vacumm leak to be found and it still runs just like yours. Like crap!