i am new to mazdas and i just purchased a 2003 protege 5 for a decent price..i have changed the iacv/map sensor/coils,,the rmp's go up and down and sometimes the car shuts off..the rpms drop down verry low like it wants to shut off at all times but stays on..when i press the gas while takin off,it drives like if i am barely pressin down on the accelerator and then it runs fine from there,,runs perfect on the highway so its basically on take off and when parked/stopped..what can my problem be??

problem #2 . car sometimes wont start on park but it does on neutral all the time..can this be a sensor or something else and where would the sensor be located if its the sensor?

 

so far i have replaced the map/iacv and cleaned the maf with maf cleaner..i will replace the maf with another 1 and see what happens..any suggestions?

 

Check the big air intake pipe from the air filter to throttle body, if it has cracks in it then that's your problem,to much air going inside. You have to take it out to check the bottom part of it. Another possibility is Egr is stuck open, you can take it out and clean it, is under the throttle body and has two 12mm bolts holding it.

 

i have cleaned the egr valve,maf sensor,replaced iacv,replaced map sensor,new spark plugs,replaced coils,seafoam'd the motor and clean all the plugs and sensors on the entire engine,replace the throttle bodie gasket,replaced entire throttle bodie,,i have tried alot of things and its still the same..it idles between 5-800(aprox)and needles goes up and down and sometimes wants to shut off and i am getting a CEL for random missfire.

 

k these cars have a recurring problem there is a hose that goes from the crank case (top of the motor) to the airbox to relieve pressure its roughly 1/4-1/2 wide hose for some reason mazda's go through alot of these hoses when my g/f bought her car thats the first thing we changed on it to a dual wall hose. if thats not the problem check all your vaccum hoses because if you have a weak spot or crack in it when the motor vaccum's air it will pinch the hose shut causing the rpm's to do the flucuate thing on my focus i have the exact same problem and on mine it was the vaccum hose going from just under the intake manifold to the pcv valve check that hose also because i know that the did change that hose to a stronger one when i went for parts. but check all the vaccum hose's it is a vaccum problem the fun part is finding which hose. hope this helps
also on the egr i know you cleaned it but did you take a pressure gauge to it to see if it holds pressure? im not sure how much it is supose to hold but if you need to know ill look in my mechanics book and find out.

 

i have sprayed all the hoses with water and soap to see if it makes bubbles and still nothing..i will check the hoes that u are talking about..i also think that it might be a vacuum leak but the problem is finding the location..i did not check the egr with a pressure gause.i am planning to take the p5 to my brothers school so they can put it on the machines to see if we can find the problem that way..

 

Have you managed to fix this. I'm having the exact same problem with me 2003 Protegé5. I recently blew my waterpump, and headgasket. Eversince I got those fixed my car is idling below 1000rpm at stops