Hi all,
I have a detonation issue in the #3 cylinder on my 1998 4.0L.
Usually occurs when under load and low RPM (like when the TC locks in OD), but can also occur under high RPM and load (like going up a steep hill at 2500 RPM).
So I ran some 93 to confirm...and it stopped. Now being that I fill my tank 4 times a week, I cannot afford to run 93 all the time.
So I seafoamed it 4 times (twice through TB and twice through booster vaccuum line).
Smoked up a storm, ran better, but no change in pinging on 87.
I then did a full tune up (plugs/wires/cap/rotor) with high quality parts.
This was when I saw that the number 3 plug was toasted -- obviously the pre-ignition issues are mainly in that cylinder. The other plugs looked perfect.
And the result? The damn thing still pings under load. 89 helps but does not resolve the issue 100%. What should I try next?
I have a detonation issue in the #3 cylinder on my 1998 4.0L.
Usually occurs when under load and low RPM (like when the TC locks in OD), but can also occur under high RPM and load (like going up a steep hill at 2500 RPM).
So I ran some 93 to confirm...and it stopped. Now being that I fill my tank 4 times a week, I cannot afford to run 93 all the time.
So I seafoamed it 4 times (twice through TB and twice through booster vaccuum line).
Smoked up a storm, ran better, but no change in pinging on 87.
I then did a full tune up (plugs/wires/cap/rotor) with high quality parts.
This was when I saw that the number 3 plug was toasted -- obviously the pre-ignition issues are mainly in that cylinder. The other plugs looked perfect.
And the result? The damn thing still pings under load. 89 helps but does not resolve the issue 100%. What should I try next?
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