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why am I getting knock???

jarredsoon

jarredsoon

Gold Member
Hey.

I have my car running 94 octane gas, I have methanol injection, about 17lbs of boost and getting 6.6 dergrees of retard and knock that I can hear. The fuel pressure is measured at 46 with the vac on and 53 with the vac off....

How come I am knocking when I am not even running that much boost??

Also when I went to the track I put c16 fuel into the car and still got some knock, still had methanol injection and still only 17 boost??? When on the track I did not hear any knock but after the run I pushed the recall button on the scan master and it showed me some up to 7 degrees retard???

I had the car dynoed and the tuner said he got no knock with 21 boost and 94 pump gas/methanol. I can't seem to recreate those figures, I can't even get my boost up that high and I never changed anything since the tuning. They told me at the track to use c16 when WOT and I would not have to worry about anything, but the scan master tells me different..... I am gonna call the tuner tomorrow but I wanna know what you guys think?

I don't know why my car is knocking, I want to get the car to run with 22-24 boost with no knock but I can't even get rid of knock at 17 boost with c16 gas. WTF.

Jarred.
 
Last edited:
Sounds false. Have you checked you DP? motor mounts? tranny mount? intercooler? crossover? exhaust? flywheel?

It's either false or a rod knock...
 
well I thought some may be false. but I know I did hear some pinging sound when the scanmaster said 6.6 retard. If I check the motor mounts and the DP what shoudl I check for?? Just make sure that the DP doesn't touch anything?? I would have to unbolt the motor form the mounts to move the DP right??

also on occasion the scanmaster reads 19.9 retard and I think that number is huge but I don't hear any pinging from the motor so I always assume that it is false, cause if that was real I would for sure hear it right??

ok thanks, Jarred.
 
If you had 19.9 you would be talking about replacing HG's not a knock lol.

Here is how you test the DP. Put your hand on it and see if you can move it.
 
thanks for the clue Jason, and I mean that. I will check tonight. I called the tuner just now and he said that the 19.9 must be false as the sensor will pick up any motor or road noise. I told him that i was getting about 6-7 knock and could hear some ping ping ping while on the road with alky and 94 pump. He said that that should not be and I am gonna get him to test drive the car next week only he is on holidays AGAIN!! and it may have to wait a few more weeks. I don't know how long I can go not driving this car, not enough nice weather in edmonton to wait.....
Jarred.
 
jarredsoon said:
oh hey Jason, what is a rod knock, just niosey pitson rod??
Click to expand...

I'll answer this one....it's the sound of money about to come flying out of your wallet!!! Hold on brutha! :eeks:

But, seriously, it's an increased bearing clearances from the connecting rod bearing failure...or if it's a double knock its a wrist pin failing.

Do you have any lifters ticking? loose motor mounts?

From your history on it I'd say your struggling with a bunch of false knock or transitional knock,at least.
 
Yeah I would not worry about rod knock.

Yours sounds false. Climb under the car and start touching everything. Something will move.

My flywheel was lose on my car causing insane false knock. I had just bought the car and it had this problem. Wanna know how long it took me to track it down?? Lets not talk about it.
 
Converter. There are 4(?) bolts. Just climb under there and tighten them until the flywheels starts to turn. As in, you are physically moving the flywheel while tightening.
 
The flywheel bolts are known for backing out. I used some Loctite on mine to prevent it from happening again. Sounds really bad when it happens too. Will be fine at speed due to the rpm but lift off the throttle or let it idle and sounds like the downpipe or exhaust is rattling.
 
Turbota6 said:
The flywheel bolts are known for backing out. I used some Loctite on mine to prevent it from happening again. Sounds really bad when it happens too. Will be fine at speed due to the rpm but lift off the throttle or let it idle and sounds like the downpipe or exhaust is rattling.
Click to expand...

Yea...I didn't use loctite but just because when you replace the tranny you will be bitching about the bolts. I'd rather check them every oil change.

But mine havent come loose in 500 miles and 41 1/4 mile passes sooooooo
 
For me I don't think it was the acceleration that got them loose, it was the acceleration followed by the deceleration that did it. I used to manually downshift to use engine braking and have better control on a few road courses I did.
 
Turbota6 said:
For me I don't think it was the acceleration that got them loose, it was the acceleration followed by the deceleration that did it. I used to manually downshift to use engine braking and have better control on a few road courses I did.
Click to expand...

Yeah. My dads GN has over 12k miles on his without needing a retighten. He actually drives it.
 
well I did a few things tonight and the car seems to be better. I put in fresh methyl hydrate because I could not get any methanol. The fuel pressure is still at 44 with the vac on. Drove around for about an hour and brought the boost up to about 17-18 and listened for knock but did not hear any. Although the scanmaster did say 19.9 alot. I have now lost the fear of seeing 19.9 retard but I find that could be problematic b/c what if I am boosting and I really do get knock?? Then I screwed, I didn't hear any ping ping ping all night though. Could it have been that the methanol in my tank was too old, perhaps evaporated a bit?? and was not working well??? and that is why I got knock??
Also I tried to find a moving part from under the hood but not under the car. All seems pretty tight, the DP, intercooler turbo, all that I could try to move.... my car is rather noisey though and I think I'll have to get under it.
 
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