Detonation (knock)
- Thread starter G-Papi
- Start date
ssinstaller
Member
- :
- 2006 MazdaSpeed 6
The motor falls off at the top end because the turbo is too small to hold the stock boost levels to redline.
(picture was borrowed from this thread: http://forum.***************/index.php?showtopic=62162&st=180#0)
(picture was borrowed from this thread: http://forum.***************/index.php?showtopic=62162&st=180#0)
I too have had an occational severe knock issue. This only seems to happen
when crusing at 20 mph and giving to motor gas (1/2 throttle) to accelerate. If you back off the gas everything is ok. Have tried several brands of premimum (91) sold here in Calif to no avail. Does the ECU flash help with this issue? Ours is an early build and we have not had the ECU or transmission software update. Thanks for any help.
when crusing at 20 mph and giving to motor gas (1/2 throttle) to accelerate. If you back off the gas everything is ok. Have tried several brands of premimum (91) sold here in Calif to no avail. Does the ECU flash help with this issue? Ours is an early build and we have not had the ECU or transmission software update. Thanks for any help.
(confused)GET THE UPDATESSS! It might help with the knock!
Rick's CX-7
Member
- :
- 2014 Mazda6
Papi,
Did you have the tranny in auto or manual mode?
Did you have the tranny in auto or manual mode?
Yes our cars knocks like a little @$@#$... I have been monitoring the Knock Retard PID from the OBD2 against boost. Most of the time the car starts to pull timing from about 3500RPM around 13-15psi, and than if the condition is right, it will pull timing again at 4700rpm if it reaches 13-14psi (anywhere from 1.5 to 5 degrees)
I am waiting for some Torco mix to arrive, and will start to see at what Octane will it stop (if it ever will). Since I live in Cali, we only have 91oct 98% of the time.
I am waiting for some Torco mix to arrive, and will start to see at what Octane will it stop (if it ever will). Since I live in Cali, we only have 91oct 98% of the time.
Can you read the charge air temp on your reader? I'm curious how warm the air is after the IC.
unforunately, there is no stock sensor/sender post IC... it's obvious too, if you look at the exit of the IC it comes to the part where the BOV sits, than it goes in to the rubber hose, and than down to the TB.
HOWEVER! I am waiting for a air temp gauge to come in, as soon as I get that I can tell what air temp is going in to the TB.
I will post some data when I have the parts and after a good long log.
One good thing though... the EGT at running cruise 65mph freeway speed is about 1300F, and WOT won't go beyond 1800F.
oh did I mention the knock retard??? LMAO
HOWEVER! I am waiting for a air temp gauge to come in, as soon as I get that I can tell what air temp is going in to the TB.
I will post some data when I have the parts and after a good long log.
One good thing though... the EGT at running cruise 65mph freeway speed is about 1300F, and WOT won't go beyond 1800F.
oh did I mention the knock retard??? LMAOcivic si hb
Member
Just curious guys why knock with the CX-7? When i haven't heard much of anything with the MS3 or MS6 and knock?
Maybe it has to due with the automatic transmission and engine load of heavier vehicle
Rick's CX-7
Member
- :
- 2014 Mazda6
Could be our smaller turbo too.
I got a Mazda6s Grand Touring Automatic 5door. Bright Island Blue and tan leather interior. The only one with that combination I could find on the east coast that had the navigation system.
I had previously owned an '04 6s GT ~ Now everything is back in the right place.
BTW ~ The knock I got with the CX was a random - unanticipated event with loads of heavy blue smoke. It had nothing to do with octane. You could floor it, get that knock - back off - floor it again, and it would run like a top.
I had previously owned an '04 6s GT ~ Now everything is back in the right place.
BTW ~ The knock I got with the CX was a random - unanticipated event with loads of heavy blue smoke. It had nothing to do with octane. You could floor it, get that knock - back off - floor it again, and it would run like a top.
Rick's CX-7
Member
- :
- 2014 Mazda6
I still have this occational knock, and I too dont believe mine is related to octane. I have only used Premium (91 in Calif) and have tried several different stations and brands of gas. The ECU and TCM reprograms were recently done and had no effect. I also don't think it is related to heat soak as it happens even when the car has been driven for up to thirty minutes. Maybe it has to do with the IMRC valve? Any ideas, dealer just says "can't duplicate the problem" and as it only happens two to three times a week I am stumped.
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I developed a knock or miss also under high load acceleration. It began after I changed spark plugs at 60k miles. The factory plugs are FoMoCo and the insulator is 1 7/16" long. The Denso Iridium plugs I replaced them with are 1 3/8" long insulators. 1/16" shorter. Since the contact in the plug boot is rigid and not springy, I thought this plug length difference could cause a small gap or just not good contact with the top of the plug. Then under high load conditions when it takes more energy to jump a gap, the miss occurs. I am going to try going back to factory plugs soon and will let you know. I also got a code P300 which is multi cylinder misfire. There has also been several, like 6 part number supercisions on the coil pack/plug boot combo but Mazda dealer can't explain if any resulted in a change in design of the contact from coil to plug. ie the spring like contact.
i know of several guys in the speed3/6 world that streched the spring in the pack to help with exactly what you are saying. i haven't personally, so i can't speak to effectiveness, but from what i've read its a viable option...
