Knock and Accessport

Jessed87

Member
Hey guys, I stumbled across a little bit of info regarding this but I wanted to see who else was noticing this. I just flashed about a week ago Cobb's new beta map for the Stage 1 93 octane with the Cobb SRI. I broke the map in correctly over the course of about 100 miles. The map performance wise is great, and I'm not reading any knock retard from the accessport during spirited driving. However when I go on to the highway and cruise at my norm of about 65 to 75 and let off the gas (even slowly) I register a 7.0 on my knock retard and it decreases over the course of about 5 seconds to zero. This happens almost every time I let off the gas on the highway, and every time without fail if I am going uphill. I know a 7.0 is not good and it has made me debate going back to a lower map to see if it continues. Just wanted to know if anyone has any ideas as to why this is happening and just how serious of a problem it is. Any help would be greatly appreciated.
 
I have no idea about why it would happen, but I wouldn't have thought twice about taking the map off.
 
i believe someone else had a problem with knock with this tune.......

www. mazdas247.com/forum/showthread.php?t=123729552

They never stated that this was the main issue but for two people to both have an issue in the same area it might be something to look into.

Is that the proper way to do links? or can i just paste it seeing it references this forum?
 
Hey guys, I stumbled across a little bit of info regarding this but I wanted to see who else was noticing this. I just flashed about a week ago Cobb's new beta map for the Stage 1 93 octane with the Cobb SRI. I broke the map in correctly over the course of about 100 miles. The map performance wise is great, and I'm not reading any knock retard from the accessport during spirited driving. However when I go on to the highway and cruise at my norm of about 65 to 75 and let off the gas (even slowly) I register a 7.0 on my knock retard and it decreases over the course of about 5 seconds to zero. This happens almost every time I let off the gas on the highway, and every time without fail if I am going uphill. I know a 7.0 is not good and it has made me debate going back to a lower map to see if it continues. Just wanted to know if anyone has any ideas as to why this is happening and just how serious of a problem it is. Any help would be greatly appreciated.
Have you data logged your stock tune to make comparisons?
BTW...which v103 map are you running?
 
Well I havent data logged my stock map being that I don't have a dashhawk..... yet. I did however try the v 102 map with short ram intake 91 octane and got nearly identical results. knock at cruising speeds. I then reflashed back to stock and now knock retard is minimal, but is still there. I believe I am using the stage 1 v103r beta 93 octane with Cobb SRI. I think what I am going to do is buy a dashhawk and see if it comes up with the same results as the accessport. I also have one step colder spark plugs on the way to see if helps with the problem. I encourage everyone to check their knock at cruising speed on Cobb maps to see if you are getting similar results.
 
Oh ok I wasn't aware the Cobb data logged. I thought you could just view your cars stats while driving. I will look into it further. Also my car is Cali spec (even though I'm in NY), so if any other Calis have this problem speak up to see if there is any link. I was thinking of installing my down pipe even though I was going to wait until spring and flash stage 2 to see if it still knocks, but I'm not sure I want to try it without the upgraded fuel pump.
 
Take the map off and compare the knock retard to stock ... people are generally getting too uptight about knock because they can see it now whereas when stock they couldn't.

My car before the Cobb AP knocked worse than after.

The cold weather plays a big role too. I find if my car isn't warmed up to about 185+ on the coolant temp, the KR will be affected much easier than after it's warmed up. See if you can see a correlation there.
 
people are generally getting too uptight about knock because they can see it now whereas when stock they couldn't.
Probably because no one even looked. Ppl don't expect a stock vehicle to knock so they don't check until they start modding.
 
What RPM range is this happening in? Many people get KR while cruising between 3-4k rpm. Sometimes I get it with light throttle, sometimes on throttle lift but its always in this RPM range.
 
yes that is the same place that I see knock retard. between 3 and 4 thousand RPMs, and always at very slight throttle usually around 10" hg or so. It doesn't matter what temp the car is at so far. It is cold here in New York so I haven't had the chance to test it in the warm weather yet. The knock retard I'm seeing is between 2 and 7 degrees, and it happens frequently. I did compare to stock and now my flashed stock ECU is showing no knock retard hardly at all at any time or RPM. This sucks because I really don't want to keep it stock, I just don't know if those levels of knock retard are safe or not.
 
yes that is the same place that I see knock retard. between 3 and 4 thousand RPMs, and always at very slight throttle usually around 10" hg or so. It doesn't matter what temp the car is at so far. It is cold here in New York so I haven't had the chance to test it in the warm weather yet. The knock retard I'm seeing is between 2 and 7 degrees, and it happens frequently. I did compare to stock and now my flashed stock ECU is showing no knock retard hardly at all at any time or RPM. This sucks because I really don't want to keep it stock, I just don't know if those levels of knock retard are safe or not.

So you flashed back to stock and logged kr? If so, did you put any miles on the stock map prior to logging?
Juts making sure as the ecu has to relearn the stock map also.
 
Just an FYI, my car, with stock map, as other have mentioned, knocks like crazy between 3 and 4k rpm. I get a KR of 6.4 sometimes . . . This isn't under acceleration either, just normal cruising. I even got it when it was -4F outside. I have read of many others experiencing the same thing. This seems to be a normal occurence, but I would double check by reflashing to stock.

Now, if you get that kind of knock under acceleration, then I would be very worried.
 
Just an FYI, my car, with stock map, as other have mentioned, knocks like crazy between 3 and 4k rpm. I get a KR of 6.4 sometimes . . . This isn't under acceleration either, just normal cruising. I even got it when it was -4F outside. I have read of many others experiencing the same thing. This seems to be a normal occurence, but I would double check by reflashing to stock.

Now, if you get that kind of knock under acceleration, then I would be very worried.
Thanks for sharing.
 
yeah I put a few miles on the stock map, only like 20 but already I do not have the highway knock problem unless I drop to 5th gear and stay around 3500 RPMs. I can also get the knock in 2nd through 4th if I go between 3000 and 4000 RPMs. It kinda sucks but it looks like without sacraficing performance it may be very difficult to eliminate this knocking. I guess id like to know if stage 2 people are having this problem. If not I'll go stage 2 ASAP.
 
Just an FYI, my car, with stock map, as other have mentioned, knocks like crazy between 3 and 4k rpm. I get a KR of 6.4 sometimes . . . This isn't under acceleration either, just normal cruising. I even got it when it was -4F outside. I have read of many others experiencing the same thing. This seems to be a normal occurence, but I would double check by reflashing to stock.

Now, if you get that kind of knock under acceleration, then I would be very worried.


Yeah thank you for that, It is good to know It's somewhat normal. I guess I'll talk to Cobb and see what they think and make a move from there. Thank you for all the constructive responses people, keep the info coming!
 
Simply try the previous revision. Sometimes the latest is not the best. This is beta and they make changes that may or may not be good.

My DH is set to warn me if my knock goes over 2KR. To date it has not went off at anytime with my current map. But that is me and I'm running a different map than you as my mods are different and I'm CA not Fed.

One of the reasons I use the AP is because my car knocked like crazy without it. I constantly saw 7KR on WOT runs and during normal driving on the stock ECU. I even ran 100Oct mix (making about 95oct) for a few tanks thinking it was fuel and still had knock on the stock ECU.
 
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