detonation issues
03-23-2015, 01:25 PM
#1
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detonation issues Was out and about the other day, everything was good. Went to down shift amd the engine started to pull then backfired and has been detonation under any load at all. I mean you barly hit the pedal and its starts detonating. I had to baby it home, almost idling to not detonate. If i very very lightly pressed throttle it would be somewhat ok yet it still missed and detonation would occur.
So i figured my fuel pump must have started to go out, but pressure is 41psi w vac 48 wo Vac.
Swapped the maf for another one, no change.
Brand new opti,taylor pro wires,and plugs
New knock sensor.
My data log shows im going super lean under load and the knock counts go crazy high. Not sure where to look next, i figured it was a fuel issue but with the gauge on windsheild underload it does not drop at all. What am i missing or overlooking?
So i figured my fuel pump must have started to go out, but pressure is 41psi w vac 48 wo Vac.
Swapped the maf for another one, no change.
Brand new opti,taylor pro wires,and plugs
New knock sensor.
My data log shows im going super lean under load and the knock counts go crazy high. Not sure where to look next, i figured it was a fuel issue but with the gauge on windsheild underload it does not drop at all. What am i missing or overlooking?
03-23-2015, 02:25 PM
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Zero dtc recorded or active
No boost on gauge at all
I did fill up a few days before at the same place i always do.
I had thought the opti rotor came loose its so bad, but it looked perfect when removed
No boost on gauge at all
I did fill up a few days before at the same place i always do.
I had thought the opti rotor came loose its so bad, but it looked perfect when removed
03-23-2015, 05:34 PM
#4
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Hmmm, Mine did this when the Opti got oil on it. I cleaned it with some 99% IPA and all was good.
Injectors could be plugged. What's the IDC reading or the pulse widths when the issue happens?
Other than that, maybe a break in the intake tube after the MAF? That happened on my Suburban once and cause these same issues. It'll get a false afgs reading and run really lean.
Injectors could be plugged. What's the IDC reading or the pulse widths when the issue happens?
Other than that, maybe a break in the intake tube after the MAF? That happened on my Suburban once and cause these same issues. It'll get a false afgs reading and run really lean.
03-23-2015, 06:44 PM
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I was leaning towards my btm possibly going out and too much timing being the issue, but not being n bost at all makes me feel like thats not it. And since i dont know of a program that actually shows the btm removing timing and what the actual timing is thats just a guess. Its not a after intake leak i have checked it alk mumultiple times. The issue im having is the car was driving perfect for about 20 minutes before amd i was pushing it good before i hit it and it started pinging and detonating like crazy. Makes me feel like its not fuel related since i had not just got gas, and somethng failed. Possible injectors issue i have had 3 other injectors clog or get stuck open. And if thats the case i have a tank issue or something. New filter not to long ago