Idle problems (2002 Protege5)…Any suggestions?

[Jinxed]

I need some help here cause I'm absolutely lost.
I have a 2002 Mazda protege5
Let's start here.
I have replaced the following already in an attempt to fix the issue.
Cat converter
Alternator
Idle sensors
Mass air flow and sensor
Redid my exhaust
Heet in the gas tank (2 weeks ago)
Checked air line and hoses
Replaced spark plugs

When driving it runs fine. As soon as I stop for any reason it will drop idle to about 200-300 when my normal is about 700-800 it's a gamble as to whether it will choke itself out or not. Sometimes it will idle fine just drop and jump, sometimes I will die immediately, sometimes it'll hold for a little and then choke.
After fueling up the car doesn't want to stay idle. It chokes immediately upon starting. I have to hold at about 2000rpms for a couple minutes before it will hold and sometimes it doesn't even do that. I have to throw it in drive and go quickly for it to not choke out.
I have hooked it to a computer and it just throws a generic code P300 if I remember correctly but I have replaced everything for that code.
Any suggestions I'll take, I'm at a loss.

 

[mazrom]

Did you check your ignition coils and ignition cables? One of them may be shot.

 

[Jinxed]

Did you check your ignition coils and ignition cables? One of them may be shot.

Yes. I have already replaced them

 

[Bruisermac]

Yes. I have already replaced them

EGR

 

[pcb]

,.. As soon as I stop for any reason it will drop idle to about 200-300 when my normal is about 700-800 it's a gamble as to whether it will choke itself out or not.

This thread might be helpful,..

P5 rough idle... Help!

My DD is an awesome automatic P5 with 183k miles, just barely broke in! The car has been great! I drive 62 miles each way to work 4 days a week and it's been a perfect commuter for a long time! Here's the backstory... I've been having a CEL code p0455 for awhile now. (Code is a common EVAP...

mazdas247.com

 

[i12drivemyMP5]

Yes, clean the carbon out of your egr and IAC and/ or go with the canadian version of egr

 

[Williamfs]

Had the same issue on an fs platform. For me it was 2 different parts:

1st time was a defective idle air control valve
2nd time was a crack on the underside of the intake hose

Both relatively quick, easy and cheap fixes. I'd recommend that you replace anyway.

 

[Shift12345]

Have you tried doing an idle relearn procedure?

What that entails:
Start from cold with over a 1/2 tank of fuel. Drive to mcdonalds (or your choice of fast-food) and order some food. Drive back to your home. Park outside on a level area, do not shut off the car.
Roll the windows down, turn off ac/radio/headlights/or other power useage, foot off brake (if possible), steering wheel straight.
Sit and eat your food with the engine idling/running for 25 minutes.
(You're waiting for the cooling fans on radiator to cycle 2 times.) Do not turn off engine yet. Go for another drive for 15 minutes, try to maintain 2700rpm to 3000rpm for at least 5 soild min at 35 to 40 mph for some part of the drive.
Also make sure to "_completely stop_" when stopping (at least 4 times).
Then drive back home, park, roll up windows, Turn off the engine, exit vehicle, and let the car sit and cool down for 3 hours.

If that doesn't show improvement, you may need to check for engine codes again, then try the relearn again.

Some people have also had luck with disconnecting the battery for an hour before doing the relearn, or alternatively just starting the car from cold and letting it idle for 30 minutes then turn it off (but results may vary.)