P0300 CEL, mazda tried to void warranty

That's because there is no way any CAI caused a misfire code.

to tell u the truth, i have no ideaman.. because this is the 3rd time that i have the cai on and off.. everytime i take the cai off, the cel goes away and my car doesn't stumble nemore.. it doesn't make sense to me either, but im just telling u guys whats happening. even the people in CPE are stumped. i'll find out tomorrow if my cai is causing it

he's already taken the CAI on and off several times now. it doesn't seem to make sense, but perhaps "no way" is a bit extreme at this stage of the diagnosis...:D
 
I had one problem, when I first installed the intake, I threw an intake code because there wasn't enough slack on the maf wires for play. I loosened them up and never had problem since.

I do not believe that the intake caused a random misfire.
 
Wow again

actually, i called CPE today and got in touch with some of the techs/engineers. they were very shocked to know that somebody actually had a problem with their CAI.. we did some troubleshooting.. they had me clean the maf, check the straightener inside the intake, and clean the filter. i did all but still no luck. the car jerks and stumbles when cruising..i put the stock air box on again, and no problem. they told me to come down to maryland.. so i'm driving down there from new york. hopefully something can be done.
thanks for keeping us updated. Very pleased you can access these guys so easily. This mystery is fun from my viewpoint and knowing that you will have a great team working on your car! Maybe you will drive home with a free or 'special' tune. Very cool. If you need Toll money i will send you a money order, but keep posting!
 
How about this one, when i picked up my MS3 with 12 miles on it I start it for the first time to drive home and the check engine light is on and it threw a misfire code. Apparently the reset procedure is to turn of the car, turn it back on and rev to 4k rpm for 2min and the car shuts down, cleans the spark plugs (i guess?) and resets the check engine light... I havent had a problem with it since but what kind of luck is that. Dealer said it must have been from starting and stopping it 3 times moving it around the lot/garage.
 
How about this one, when i picked up my MS3 with 12 miles on it I start it for the first time to drive home and the check engine light is on and it threw a misfire code. Apparently the reset procedure is to turn of the car, turn it back on and rev to 4k rpm for 2min and the car shuts down, cleans the spark plugs (i guess?) and resets the check engine light... I havent had a problem with it since but what kind of luck is that. Dealer said it must have been from starting and stopping it 3 times moving it around the lot/garage.

lol! Kinda of kills the "new car" feeling doesn't it?
 
well this is some stick situation lol. after working 16 hours and having no sleep for more than a day, i drove my ass down to maryland to meet up with CPE techs. let me tell you guys something. their shop isn't anything special from the outside.. but inside WOW..they have all the products that they make.. and they're all there working very diligently to perfect it!!

i met up with josh.. i think he's the owner. he gave me a tour of their place.. and it's amazing what they do. all their parts were there, standbacks, intakes, exhausts, etc..and some "new" products they're coming out with =D

after this tour, he came over to check out my car.. and after a minute of just looking at it, he told me the problem. the TURBO INLET pipe is loose. he told me that this is my DEFINITE problem. he also told me that several people have complained about this, and it is a common ms3 problem?? i had no idea what the turbo inlet looked like cuz i'm a newbie.. he showed me how the whole thing actually works and how it moves along when the engine torques. i also got to see the difference in tightness of my inlet and their ms3.. and damn theirs is so much more rigid than mine.

he woulda been able to fix it for me, but his schedule was so crammed and he said it would take a few hours just to take off the i/c, the hoses, wires, etc.

he ran a diagnostics again and surely, my car still had the code p0300. he said i was still getting a random misfire but not to the extent when my car jerks and stumble like it did with the cai. the reason is because with my cai, i had unwanted air coming in, causing it to misfire. with the stock air box, i had the same problem but not as "bad" as when i had the cai.

well that was my experience with CPE. i definitely missed some parts of it, but u guys get the picture right? i spent money on gas and toll, but the experience was definitely cool. CPE was very good to me, they were very apologetic and felt really bad that my girl and i went down there to find out i had a loose inlet lol. he wanted to take me out to lunch and stuff but i really needed to get home so i had to get outta there. and plus i was running on 1.5 days no sleep =/
 
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Yes. Most OBD2 systems will reset within 50 key on/off cycles if the problem doesn't happen again. If you have an advanced OBD2 scan tool you can check freezeframe data and see how many cycles occurred after the code set.

Look up what a misfire is. If you had ONLY a P0300, you probably had a fluke code. It happens. Typically when you set a P0300 and there is an actual misfire, you also set a code for the cylinders that have experienced a misfire, P0301, P0302, P0303, etc.


$1,000,000,000 says this code is a fluke. Had it been actual problem, simply putting on the intake would not have caused the code to go away. You would have had to wait 50 key on/off cycles for it to disappear after solving the problem(s), unless you reset the ECM. That in itself says the problem was not caused by the intake system.

Dealer tech's are just taught that OEM parts work ok, and aftermarket parts cause problems. *Most* of them are idiots when it comes to performance and engineering altogether. What are they good at? Following procedure and diagnosing issues(usually). Notice I said *most*.

he told me that taking the cai on and off and the code going away was just a coincidence.. truly the cai didn't "cause" the misfire but it makes a difference in the car because the cai takes in more air than the stock.
 
thanks for keeping us updated. Very pleased you can access these guys so easily. This mystery is fun from my viewpoint and knowing that you will have a great team working on your car! Maybe you will drive home with a free or 'special' tune. Very cool. If you need Toll money i will send you a money order, but keep posting!

hahaha thanks for the offer man, but it's kool.. the money spent was worth the experience. he told me to call up and keep him updated and later on, he'll work out a deal with me on some stuff =D
 
well i now have an appointment with mazda on monday, i'm gonna complain about the leak and how it is messing with my car. they gotta fix that up cuz they're going to hear it from me if they give me problems about fixing it
 
well yea, according to CPE, the cai goin on and off my car and the CEL going away was just a coincidence

Well I would assume you reset your ECU by pulling the negative wire on the battery anyways right? If you did that, the code would go away for a little while anyways.

As for the inlet pipe, it's junk. ATP's site has the comparison between theirs and the stock and it's pretty sad to say the least.

Keep us updated on the inlet situation when you get it back from Mazda because I'm interested in hearing their excuse.
 
Well I would assume you reset your ECU by pulling the negative wire on the battery anyways right? If you did that, the code would go away for a little while anyways.

As for the inlet pipe, it's junk. ATP's site has the comparison between theirs and the stock and it's pretty sad to say the least.

Keep us updated on the inlet situation when you get it back from Mazda because I'm interested in hearing their excuse.

yep, i'll keep u guys updated. i'm pretty sure they're gonna blame it on something but as for the battery, no i didn't reset it. which is what makes this whole thing weird. i'm thinking that the CEL comes on because when i have the cai, it's sucking more unwanted air than the stock. probably just coincidence
 
Sucking more cold air is the point. but it would not cause a random misfire. If anything the car would throw a lean code. I'll 50 bucks down that it is not the CAI. What it could be is that the MAF wiring house could not have enough slack and could be jerking a little to much when you are driving spiritedly. But in any case, that would just throw a CAI code.
 
Sucking more cold air is the point. but it would not cause a random misfire. If anything the car would throw a lean code. I'll 50 bucks down that it is not the CAI. What it could be is that the MAF wiring house could not have enough slack and could be jerking a little to much when you are driving spiritedly. But in any case, that would just throw a CAI code.

oh yea i know my car is running lean now..i didn't say the cai caused it. the turbo inlet pipe is loose, and having the cai is making it worse i guess. i dont know for sure what the cause is, but i know that the loose turbo inlet is messing up my car. that's what the cpe tech told me, he said from driving around and flooring it, the pipe becomes loose, and it's been a problem from mazdas.
 
Does anyone have a full map of our engines? If not, can somone please tell me where the trubo inlet pipe located and if I can get to it from underneath the car.

I just threw the same code but haven't expeirenced any studer or anything. I am thinking that my bypass valve has gone bad b/c I have also gotten some codes for burning rich during idle. I just purchased the forge to change it out but I also want to tighten my inlet pipe....please help.
 
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