4000 RPM Fuel Cut STILL

[icecold0027]

My two previous posts on this issue
http://www.msprotege.com/forum/showthread.php?t=123621853
and
http://www.msprotege.com/forum/showthread.php?t=123621061

I took the car to the dealer and they told me it was the spark plugs. They had never been changed and to my surprise they really needed it. I dont believe for a second that this was a spark plug issue. Anyways I put Bosch 4+ plugs in for the time being and the problem still occurs. Its getting worse and worse now happening at 3100 and below. The dealership is going to come back and say its because they are not the OEM plugs. Hardly anyone on this forum has OEM plugs. So what should I say to them???
I bought the Bosch plugs to prove that it wasnt the plugs but after being interigated about what plugs I was using when I dropped it off I know they are going to say its because they are not OEM.
Does anyone think that this could be result of the plugs???

 

[smo0f]

you put bosch into an msp? mmm. bad, i think.

 

[A.V.MSP]

you are running the 4+ plugs? dude you will be detenating like crazy

 

[boostisgood]

NO NO NO NO NO NO NO. Get those out and get the OEM plugs. NEVER EVER EVER EVER EVER put NO OEM plugs into a car, unless your are heavily modded. (I.E. forged, running 12+lbs of boost ect ect)

do you have a boost gauge? If so, what PSI are you hitting ? IT sounds to me like the actuator for the Wastegate is stuck open. I see more threads about it popping up recently.

 

[A.V.MSP]

also how cold is it where you live? but yank those plugs out now they are waaaaaaaayyyyyyy to hot and youll blow it up

 

[BBSF2]

just use the ngk's. they are the best plug for the mazdaspeed and many people use them on this forum.
craig

 

[smo0f]

yea dude, get some NGK's in there. Anything else will fux it up. Read the spark plug sticky for more info.

 

[icecold0027]

holy hell that more replies than I ever thought. Well I guess I dont know s**t about what I am doing. Ill get the NGKs. The OEM plugs are NGK though. They are the ZFR6Fs. Exact same ones I just pulled out. Thanks guys ill take care of that stat.
Also Ive ready the sticky thread and the bosch plugs are on the very first list of plugs you can run

 

[icecold0027]

dealership got back to me...its a torn diaphragm in the Waste Gate actuator. they have to order the part but the whole procedure should only take a couple of hours. I will definately change those plugs as soon as I get it back.

 

[BBSF2]

well, it could have been worse, it is a simple fix. good luck with it!
craig

 

[jeffmsp]

makes sense. im guessing you dont have a boost gauge? good thing the fuel cut was there or your motor would have gone bye bye the first time you put your foot down, especially with those plugs and 91 gas.

 

[icecold0027]

So can someone tell me why those plugs are so bad and what makes the NGKs so good.

 

[BBSF2]

its not that they suck, its just that many members have had bad issues with bosch. also, they are a lil pricy. ngk's are used by many people and have had really no problems, while bosch have caused problems. the boosted motors just like the ngk's more. if u do a search of why bosch isnt recommended, you will probally find your answer. here is just one thread about it.
http://www.msprotege.com/forum/showthread.php?t=123619457&highlight=bosch+plugs

 

[smo0f]

the general thumb of rule is, ngk's are for Japanese cars, bosch are for euro, and autolite for american. always get the stock brand for your car, with higher boost you would just have to go 1 step colder, but they will foul out on stock boost levels