Hey guys, I'm having an issue with my Greddy Turbo AP1. I believe I am hearing detonation above 6k rpm under acceleration, it sounds like a pretty loud crackling noise. I pulled the plugs today and this is how they look (this is the worst one):



To me, the plugs looks terrible and it seems as though I'm getting some detonation for sure. The motor seems healthy, doesn't burn a drop of oil and the car has been perfect during my ownership... I'm worried that I may have done some long term damage to the motor if I've been driving it like this though.

My question is, what do you think of the way the plugs look and how should I go about troubleshooting this? Is this all in the tune or could it be a fuel pump thats on its way out?

The car is tuned on Hondata Kpro and has the following:

RC 550 Injectors
Walbro 255
No wideband gauge at the moment

Thanks for the help!

 

what type of plug do you have? was this a problem that just started? meaning that the car had been running up to redlined as tuned without issues before?

 

The plugs are NGK BKR8EIX. It's weird because the problem started a little while ago, but the car runs perfectly, its just that I can hear it detonate/ping. It only happens in gear 2 or higher and above 6000 rpm... but the plugs look terrible, no?

 

you say the problem started a little while ago, so just to be clear, the reason im asking is because it makes a difference in where you look for your problem...how long was the car running all the way to redline without breaking up above 6k?

 

No problem at all, i'll provide as much information as I can.

The car started this last season, but I drive barely 2k kms per season so this has been happening for maybe 2k kms or so.

It doesn't break up though thats the weird part, it makes power all through the RPM band and it runs great, but the plugs are telling me its running lean and detonating, no?

 

ok, so the problem started last season, was that when the vehicle was tuned? and the noise you described as a loud cracking, yes, that is detonation, and no, thats not normal. that means it is not running correctly but the problem is, i have no way of knowing whether the vehicle ever ran correctly under boost by the way youre describing it on here..

 

No the vehicle was tuned well before that. I'm not 100% sure if its been detonating this entire time or not, but I highly doubt it. The last time I changed the plugs they looked fine. I only started noticing the noise for the last 2k kms or so and only under the conditions I initially described. I have no problem getting the car re-tuned though.

Also, my fuel pump whines when its very hot out and when the gas tank has less than 1/2 a tank of fuel in it (I try to avoid this as much as possible), but it has always done this and the noise hasn't gotten any louder or worse since it was installed - I've been told Walbro fuel pumps usually whine like this.

Thanks for your help btw!

 

the joke about walbros is that they are whiny bitches..lol...and you would hear it more on a hot day because it would require more fuel on a day like that, so you are going to hear the noise more at that point..


ok, so it sounds like the car was tuned and running all the way to redline at wot with no issue, i see carbon buildup on the plug, was there any oil on it?

 

There was a very small amount of oil on the bottom of the threads of the plug, no oil in the spark plug wells either.

 

i was just checking, because if you have a valve cover gasket with tube seals that are leaking into the cylinder like that, that will cause a misfire too...it wouldnt help to replace the plugs if you havent addressed the oil leak..


at this point, if thats what the plugs look like id say they might need to be replaced, although you say that youve only got maybe what....3-4000 miles on those plugs...its also a little difficult to figure out because we dont know what afr you are running, what turbo size, what all the specific details of the tune are...there can be a LOT of different things that can cause an ignition system to detonate..

 

Okay, I am going to change the plugs regardless, I just don't want to be doing damage to the motor, but i'll definitely lay off it until I figure out the problem.

My next step is to put some fresh plugs in and get a wideband gauge. Also, as far as the plugs are concerned, what about the way the plugs look right now is concerning or how should they look differently in the future?

I just want to be able to monitor them myself as much as possible.

 

Get a wideband installed unless u want to rebuild the motor. Plugs look warm... Fuel pump could be dying leaning u out. Wb02 asap

 

This should help you:

http://www.4secondsflat.com/Spark_plug_reading.html

It's basic plug reading. I'm not good at it myself, so I thought I'd just let you read it and determine it yourself.

 

Yeah I will get one right away, what do you mean by plugs "look warm", and yeah I think I may change the fuel pump as well.

Thanks guys!

 

Thanks, I read a few spark plug reading guides but I'm still kind of new to it so I'm not sure if I'm correct in my assessments.

 

id never dealt with the bkr8's myself, the bkr7's when i had over 5000 miles on a set of plugs on a t3/04e i would see them starting to break up...those were on rc440s with 9.5:1 compression ratio up in virginia about a decade ago however...the noise you were describing does sound more like that, the reason i was questioning an oil leak was because you were saying it didnt seem to be losing power, which when it starts detonating, depending on how bad, you may or may not feel..