Random hesitation, almost stalls
 

I have a 01 2.0lx auto.
the car has 107,000k miles.

Im on my 2nd set of plugs, wires, and coils since I purchased the car. recently the car will randomly hesitate and the rpm's drop so low the car feels like it will kill.
because im on my 2nd set of coils and wires (1st set was warrantied due to above problem), i feel that it is not these parts that are randomly going bad, but another part in the car causing these specific parts to go bad.

the car is all stock. the cel is on due to the secondary cat (been on since I purchased the car).
I recently had the car scanned and the only code was for the cat, no codes for ignition or coils.
would the cat cause ignition problems?
anyone experience this?

tia.

I have '01 protege w/ 2.0L. I had this prob. The air intake hose between air box and engine was cracked. engine idled fine, when putting a load on the motor the engine would move and the unseen crack in the afore mentioned hose would open. This lets more air into intake and the engine would almost stall. I'd throw it into neutral to keep it running. while under hood clean the batt ground near the battery and the engine ground at the rt side engine mount. please post results thanx.

If there is no Check Engine light, then it's likely a vacuum leak or intake system leak.

If the CEL is on, then it might e a fouled EGR valve.

when I warrantied the parts, they lasted for about 8k miles before this problem started again. when i changed the parts the car ran and idled perfect.
this hesitation/rmp drop happens randomly, under load or not.

I checked for a cracked intake tube and for leaks, and everything looks fine.

go to the Protege forum and look for the 04-13-2009, 10:30 AM post by Adam S, entitled
I have a 2000 Mazda Protege, 1.8L with 5 speed manual transmission @ 190,000 kms. There you will find some stuffwhich might help deal with these stubborn intermittent things. Beyond this, you should check your throttle linkage at the pedal to throttle, where dirt, loose bracket mounting etc. have caused your sort of grief. Another suspect is the IAC (idle air control), either through corroded actuator contacts or a sticking actuator.
On a point of interest, does the car behavior change when you run with the air conditioner on? If so, this points to an intermittent/ sticking IAC issue.

try looking at the pcv hose that goes from the back of the intake manifold to the pcv valve don't look at the valve its self it is fine look at the hose if there is an indent or a crack that could be your problem.

would a crack in the hose (pcv hose, intake hose, etc...) cause the coil to go bad?
if i change the coils, the car would run fine.

Egr
 

Check your EGR valve. I have the same problem, I had my tech remove it and it was indeed jammed. We cleaned it out lubed it up and it solved the problem.

i agree check the egr, I had a problem with that a few years back and that was the problem.