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Knock because of crank pulley or fuel pump

comongoose

comongoose

New member
Ok so I just got over my last issue of the car not starting due to a malfunctioning CPS. I was then having trouble with putting the crank pulley on the right way. I put it on not keyed the right way three times in a row. On the second to last time I test drove it, the idle was high, and the idle would surge real bad. Also when i floored it, the motor got up to 70 on the knock sensor. I took the crank pulkley off again to confirm that it was on wrong for the third time, as I etched a new notch right between my last notch i etched and the real one from GM. I do not understand why the crank does not have the bump go all the way down the crank shaft. its like a guessing game every time. This last time I put it on it felt real good. The idle is now a little lower and it wasn't surging at idle. Then i took it out and at the peak of rpm i was getting anywhere from 7-33 on the knock sensor, but non when driving normal or giving it some gas. Then when i parked in the driveway it was surging a little. I could also hear the fuel pump whining with the rhythm of the surge. Mind you when i first put my motor together it had no knock and ran like a champ. However I am not sure if I had the back knock sensor connected or not when i ran those tests originally after the put together. I think i only had the front one connected. Do you guys think that I still have the crank off a little bit or does it sound like the fuel pump is failing on me now too? If you guys think it is the crank being off does anyone have any tips on how to get it on right? I pushed it down and its always hard to spin it so i never know when the pulley is keyed in right. Below is the link to the thread that explains how all the problems started with my ignition problem, if it might provide clues for you. Thanks a lot in advance for any input. BTW i am still running the stock pulley, but have all of the other mods in my sig.

http://www.grandprixforums.net/f18/ignition-problem-icm-or-fuse-14267.html
 


I have never had any troubles putting the ballancer on. Just put the key in and slide it on. Maybe turn it a little untill you feel it catch the key. Then torque it down.
 
well the key is half way down the crank so by the time i get it down there it is to tight to twist the pulley. Does the key start at the beginning of the crank for you? some on clubgp suggested i knocked the key back into the cover.
 
Oh ok I see wat you mean now.



I just lined everything up and torqued it down.



I can tell you the surge in idle is not from this. IF the ballancer is not on correctly you may notice increased vibration if anything. But that's about it.

The fuel pump fluctuating is more than likley from the idle fluctuating. Because the voltage in the electrical system are also fluctuating. And that's what is causing the fuel pump to do that.
 
yes, the sensor is on the crank pulley but i cannot see how you would be able to get it all the way on and not in the key. The belts would be misaligned and the bolt probably not long enough.
 


minichopper6hp said:
yes, the sensor is on the crank pulley but i cannot see how you would be able to get it all the way on and not in the key. The belts would be misaligned and the bolt probably not long enough.
Click to expand...

no i get the pulley all the way down. Like i was saying earlier the key just engraves a new notch into the pulley. So the belts align and the bolt goes all the way down. Therefore i figure the pulley can be off a degree or two and mess up the timing of the ignition.
 
not that hard, i think that metal is not that hard as well, but it feels like it takes some pressure all the way down.
 
Also I remember reading somewhere that the scangauge is off a decimal on the kr reading. So 73 would be 7.3*. Can some one confirm this? If this is true then my problem is no where near as bad. Also I read that if the knock spikes and doesn't gradually increase to the number at wot it is fake knock. I noticed it spike and doesn't gradually reach the high kr, so could someone confirm this to be fake knock? I have heard some weird vibrations from the exhaust. could this cause it?
 


comongoose said:
Also I remember reading somewhere that the Scanguage is off a decimal on the kr reading. So 73 would be 7.3*. Can some one confirm this? If this is true then my problem is no where near as bad. Also I read that if the knock spikes and doesn't gradually increase to the number at wot it is fake knock. I noticed it spike and doesn't gradually reach the high kr, so could someone confirm this to be fake knock? I have heard some weird vibrations from the exhaust. could this cause it?
Click to expand...

I asked Scanguage about that cause there is no decimal point in the KR readings.
They told me that they did not forget the decimal point and the readings are accurate.
But other owners have said that there in fact should be a decimal point because the readings they get when other scanners are used say otherwise.
I do think that a reading of say 38* KR with a Scanguage should be 3.8*.
I have read about the same thing.
 
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