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View Full Version : Is my engine detonating?


warauto
07-23-2009, 07:59 PM
I have a stock redtop in an s14, when i get up high in rpms...like 6000 -7000 in any gear my car stutters, kinda like the stumbles a little bit. I dont know if i am experiencing detonation....?

moses
07-25-2009, 02:48 AM
It does sound like it. You can tell if you pull out your spark plugs and they are white. Or even better since your going to need it sooner or later you can get a wideband o2 sensor. Do you have a stock fuel pump?

fliprayzin240sx
07-25-2009, 11:16 AM
Either that or your car is advanced. Like stated, pull the plugs and check em. You see white spots around the ring, definitely detonation.

Whats the spec on your setup? Boost, fmic, fuel pump, fuel management, spark plug are you running.

SilviaSR20DET
07-28-2009, 08:15 AM
or it could be your spark plug gap that may be incorrect? Need to get colder spark plugs? might give that a try. If you were detonating youd hear it, its pretty noticeable.

steve shadows
07-28-2009, 11:55 AM
I have a stock redtop in an s14, when i get up high in rpms...like 6000 -7000 in any gear my car stutters, kinda like the stumbles a little bit. I dont know if i am experiencing detonation....?

No...

But it is misfiring.

knock sounds like sand in a tin can rattling around it's a pretty soft sound, you will notice a loss of power but it wont feel like you are hitting a wall.

If it's that bad your motor should already be totally gone...

It sounds like ignition grounds, check your Coil Pack harness grounds to back of head and firewall as well as all ignition conntections. Also check your Fuel Pressure under high load and see if it is dropping off, old walbros will do this.