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Don't take the knock sensors signal lightly. I had the same issue, after reading some guys saying that it might be a false signal, I didn't take it to serious. My engine blew due to knock. It's costing me an arm and a leg to fix it!

If it's knocking, GET IT FIXED! There's nothing more serious, It won't be long before you break a ring land.

The knock sensors do occasionally give out a false signal, but if it's happening often then more than likely your engine is knocking

Back off the timing a few degrees

If you can't access a tuner, go on youtube, type in power fc tuning, there's a good video on how to do it.

If I remember right, it was some guy with an rx7 that posted it on YouTube

If you can't find the vid, shoot me a msg and I'll find it for you

  • Like 1

I have no access to a dyno as most people here would know. I also have blown up motors due to knock and some serious detonation in the past. And from then i have been struggling to tune my power fc using the road, and what ever sensors i have. I can say that i appreciate any sensor rather than none. I haven't gotten bad results but i can truly understand when guys tell me i need a dyno and im working blind. That statement is very true as ill never know my max torque line. What i would recommend is have a good read over paulr33 FAQ. and understand what the man is saying under the self tuning section. That was the real foundation to my learning. But power fc knock for my is a clue. It cant be that bad. But if you have lots of loose parts slapping against your engine block that can be interpreted as knock as well. So that being said a clean and organized engine bay is very good. You are bless take your car and get it tuned mate. You should love it after that.

I'm of the Opinion that sometimes your tune may be fine for the batch of fuel you used to tune the car on initially and you can get the occasional knock from lesser quality batches of fuel also.

I wouldn't be too quick to change the tune because you may be adjusting it to suite a bad batch of fuel, knock it down a few degree momentarily on your base map just to get you by if you have too and put the fuel you would normally use in it and maybe it will just settle back down again.

Ignition Maps can often be set right on the edge which doesn't leave u much of a buffer for hot weather and especially when on a dyno your bonnet is usually up and engine bay is running nice n cool when on a road you could be sitting in traffic for 20 minutes with no clean air then you give it a hit and see knock.

Knock of 100+ is ridiculous you should be getting a reasonably loud knock rattle even at 50 to 60% generally speaking but loosely fit motors which have been rebuilt do make more noise so it can be deceiving.

if your engine is tight around the 20% knock I would accept.

Pull out the coldest plug which is normally number 1 and the back plug number 6 which is the hottest and inspect also the porcelain tip of your spark plugs will show signs of detonation and and severity I of it.

when I tuned my car on Optimax 98 ron I would try caltex or another 98ron and from my usual 16 to 20 percent knock reading it would shoot up to 48 50 s just by putting another brand 98 octane In i would have to remove at least 2 degrees to bring the knock back down.

Hope any of that useless info helps a little

Edited by mr skidz

Thanks for the info guys, I'm going to buy a couple more things for the car and then get it tuned. For now I'll revert back to the stock ecu, even though I'm sure there isn't any knock and it's just something rattling. Can't be to careful.

I brought the timing down -3 degrees which seemed to help a little, and will check the plugs on the weekend.

For now though, I'll wait on injectors and a turbo and then tune.

Cheers!

Sorry to jack the thread, just put a power fc in my 32 with a 25neo in it, did an initialise then did the self learning idle bit... Now when I rev my knock jumps up and ecu goes into limp mode..

So now I can't rev over 2k, are my knock sensors throwing out a fault reading? What do I do?

Edit: just did another initialise and it doesn't limp anymore, but the knock Sensor still jumps around a fair bit, at 4k it'll nearly max out

POWERFC doesnt have limp home mode so something is amiss.

a sure fire way to check if you have erroneous knock levels is to start the car with the peak set on knock monitor if its reading 40-60 you know its useless.

Do you mean monitor the knock level as i turn it over? and if it jumps up then its just a rattle? i feel like to be safe ill run the standard ecu for now until i buy some more gear.

To guage why its knocking.

Your injector map might have enough fueling in the table but that doesn't mean it's physically going into the motor so I changing to a standard computer won't help a blocked or tired fuel filter fuel pump injectors excetra could even be a fuel Reg not holding pressure who knows give it to the Experts.

So many variables

Edited by mr skidz

Yeh, out of curiosity will a car knock only on load? If I rev in neutral it doesn't seem to ping..

I honestly can't answer that I've never had a car that porely tuned that would knock by freely revving it in saying that anything's possible.

Pinging generally shows up when intake air temperature increases directly from Boost that is the reason why it's so important to have timing correct as boost is introduced to the map and also enough fuel to cool the combustion temps avoiding detonation altogether you should never have detonation.

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