Spark Knock (1 Viewer)

[Bear80]

As I have been driving the 80 while installing my new lift for the mini, I have noticed a very annoying spark knock. It never spark knocks pulling up a hill or on sudden applications of throttle. The spark knock only occurs when you barely apply throttle to keep up a moderate speed, for example 30 mph or so.

As a side note, I also noticed that my rpms drop right back to idle when I lift off the throttle regaurdless of low or high rpm and when I go back to lightly apply throttle it knocks. It seems the computer is not or cannot do anything about it. If I apply more throttle it stops. I'm thinking my issue with the rmp's dropping down is part of the problem. As I know my 22r and 3vz use a "dash pot" (?term?) to keep the rpm's from falling to fast when you lift off the throttle. I'm sure this is the same on the 1fz but anything else I should maybe look for?

 

[powderpig]

Hook up a OBDII reader/computer program(they have been discussed in other threads) and take it for a drive see what is happeneing that may still be in the paramiters but not triping a code. Yes there is a dash pot on one side below the cables. May be looking for light throttle lean condition. May jsut want to check and adjust the throttle position sensor. good luck robbie

 

[whodat]

spark knock=pinging?

 

[Bear80]

so I can try this with a hand held OBII reader?

 

[powderpig]

No hand held code reader, you need some real time data logging, like a computer based or OTC, snap on, screen based data reader. late robbie

 

[Bear80]

No hand held code reader, you need some real time data logging, like a computer based or OTC, snap on, screen based data reader. late robbie

Well that pretty much puts it out of the question.

 

[tarbe]

I have the exact same deal. Only goes away with 91 or better octane. I'm finishing up a tank of Chevron Supreme 93 right now and it has been nice not hearing that dang noise the past 10 days.

I've run BG-44K, Schaeffer's Soy Ultra, Marvel Mystery oil, Seafoam (in the tank, not up the PCV) trying to clean out the carbon I suspected was the culprit. I am chicken to do the water treatment...plus I wonder now if it is carbon or something in the management systems.