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Discussion Starter #1
So I was cruising down the highway at aprox 70 MPH in sixth. As I approached a slight incline in the road I lightly rolled on the gas. Several seconds later I experienced audible knock and an immediate boost / fuel cut. After reading all the stories on here I nearly crapped my self :eek:. Fortunately, everything quickly came back to normal, and I drove the rest of the way home.

I had been regular street driving for about 45 minutes before this happened. BAT was < 130, FP was fine, EGT was normal. I'm running 93 Oct, and have a SMOCC installed. I know about not getting into boost < 3k, and even if I did, it wasn't very far, only had it at about 1/4 - 1/3 throttle. I am prioritizing the AP purchase now to cut the boost.

I noticed during some testing the other day that I would get some KR in 5th or 6th with engine load > 30% and RMP < 3k, but only after warming up for 5-10 min. Could some of this KR be coming from hot plugs :confused: ? Would going a step or two with stock turbo @ stock PSI help anything? Will I foul 2 step colder plugs on stock boost?

Thanks all!
 

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How's your oil level?
Any mods?
 

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Discussion Starter #3
Oil's good, just changed it ~700 miles ago. Only engine-connected mod so far is a SMOCC.
 

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2 step is too much stock. if you do some regular spirited driving u will be fine on the 1steps.
 
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Plugs is a goo start. And always make sure you shop carefully for your gasoline.
 
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You just got some crap fuel. It happens even at a "good" gas station sometimes. I've had it hapen once before as well. Well, not the fuel cut and audible, but I've seen the KR with the cruise on when heading up a slight hill before. The ECU has the timing fully advanced at cruise and when the load increases, it knocks slightly and the ECU pulls the timing back into the right zone fore the load.
 

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Oil's good, just changed it ~700 miles ago. Only engine-connected mod so far is a SMOCC.
All OCC lines run smoothly, no pinched lines?

You just got some crap fuel. It happens even at a "good" gas station sometimes. I've had it hapen once before as well. Well, not the fuel cut and audible, but I've seen the KR with the cruise on when heading up a slight hill before. The ECU has the timing fully advanced at cruise and when the load increases, it knocks slightly and the ECU pulls the timing back into the right zone fore the load.
Crap fuel is def. a possibility and would be easy to check for, just go WOT and see if you get any KR.

I've never had any audible knock / cut when my DH registers knock retard during highway cruising and it has been doing this since day one.
 

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I wouldn't go WOT until you run that crap fuel out of your tank, and fill it w/ some Shell 93 or equivalent.
 

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I wouldn't go WOT until you run that crap fuel out of your tank, and fill it w/ some Shell 93 or equivalent.
pretty much, run it down till the dummy light comes on, fill with new fuel, still give it time and run that last bit down, refuel, and you should be good to go.

I hate getting bad batches of gas (when on long road trips) last time was BP fuel. damn this car hates that shit. best fuel i could find in redneck north florida and alabama :S
 

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Discussion Starter #12
+1 for the Shell. Had been running Road Ranger 93 + 10% because it was on my daily route. Been through 2 tanks of Shell 93 + 10% and haven't had any more audible or cuts, though there are definitely some KR blips in 5th and 6th (0.4 - 0.6 under mild accel, is this usual?). Will probably change the plugs in a week or two to see if I can reduce the KR bounce a little more.

BTW, for the BP gas... is salt water an octane booster or reducer? :hide: :D
 

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Good for you guys that you can get 93 octane fuel. Out here in Ca its only 91 unless you buy 100 at a racetrack or something. I remember this audible knock happening even with Chevron or Shell 91 when I only had an intake. Happens a lot less with my AP OTS stage 1 map. But it was always when I nailed the gas in 6th gear at low load, it took me a couple times to realize that you must downshift in that situation.
 
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