spark knock maybe, and question about timing w/ 4*advance cam

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Jan 1, 2007 | 02:53 PM
  #1  
I've had a rattle for the last couple weeks. Occurs from 1500 to 1700 rpms under light to medium loads. Won't do it while in neutral. It has a sort of pulsating frequency to it that slows the higher the rpms get until it goes away. Like something that is spinning and rattling. Kinda hard to describe.

It's a brand new 3.4. The cam is a stock size replacement from comp-cams and has a 4 degree advance grind. Would that 4 degrees cause my timing to be too far advanced when I set it at 10?

I can't get ahold of the manufacturer today, but I'm tempted to go out and retard my timing a bit to see if that makes a difference.
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Jan 1, 2007 | 03:01 PM
  #2  
go pull 2* of base timing,take it for a drive,if it still does it pull 2 more*,if it doesent go away by the time u have pulled around 6-8* more then likley its not
spark knock

btw even though the cam is advanced once u set ur timing its
set if it says 10* its at 10*.and most cams come 4* advanced
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Jan 1, 2007 | 06:34 PM
  #3  
Well I set it at about 6 1/2, took it for a drive, and still heard it. Road is wet and it was raining a little so it was hard to hear much, but it was still there. I only adjusted it once because it's a pain on my car. I get shocked if I grab the dist and plug wires while it's running.

So now I guess I get to worry about rockers or bearings probably. yay

I did find out why it doesn't start up on the first crank when it's cold though. My CSI is disconnected. Must've happened when I was fighting with the wiring trying to get my o2 connector to reach, because now I can't get the CSI plugged back in. oh well, I'll deal with it another time.
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Jan 1, 2007 | 08:04 PM
  #4  
Quote: Well I set it at about 6 1/2, took it for a drive, and still heard it. Road is wet and it was raining a little so it was hard to hear much, but it was still there. I only adjusted it once because it's a pain on my car. I get shocked if I grab the dist and plug wires while it's running.

So now I guess I get to worry about rockers or bearings probably. yay

I did find out why it doesn't start up on the first crank when it's cold though. My CSI is disconnected. Must've happened when I was fighting with the wiring trying to get my o2 connector to reach, because now I can't get the CSI plugged back in. oh well, I'll deal with it another time.
I was having a simular problem when I did my swap and had to relocate the ground from block to frame( refering to the shocking when adjusting timing). have you tried that?
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Jan 1, 2007 | 08:18 PM
  #5  
I'll have to try that I guess.

Also, that sound seems to be coming from the right side of the engine. That's what it sounds like when I shift my body so my head is centered over the console.
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Jan 2, 2007 | 07:06 AM
  #6  
if youre getting shocked you need to replace your wires or cap or whatever is shot because you sure as crap shouldnt be getting shocked.
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Jan 3, 2007 | 09:18 PM
  #7  
I think I remember getting shocked even when the cap and/or wires were new. I should try a new distributer though. I'll have to take a look at it anyway in case that's the rattle. Or maybe my flexplate bolts.

I found out my idler arm is bad today too. Hopefully when I get it replaced and the tires stay straight, I'll gain a tad more mileage.

By summertime when the gas is better, and I have enough miles to switch to synthetic, if my mileage hasn't improved ( and I have my truck) I might put my 2.8 back in until I can figure out where I went wrong.

I'm still getting about 7-8mpg less than the 2.8 right now.
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Jan 3, 2007 | 09:44 PM
  #8  
ur using 3.4 injectors right? i bet u when its cold it prolly runs pretty dam rich,and when its idling its idling as lil richer then normal.which could make up for some of ur mpg loss,not much but a lil,
what gears does the car have?
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Jan 3, 2007 | 10:14 PM
  #9  
I haven't really driven mines that much since I put the 3.4 in. I did use the 3.4 injectors though so when I get it out if the exahust shop (couldn't get the y pipe all the way tight to the manifolds) I'll run it for about a month just to check on the mileage to see what I get. I did switch to mid grade gas with 10/40 oil. Don't know what that will do just seemed like a good idea.
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Jan 4, 2007 | 10:40 PM
  #10  
Quote: ur using 3.4 injectors right? i bet u when its cold it prolly runs pretty dam rich,and when its idling its idling as lil richer then normal.which could make up for some of ur mpg loss,not much but a lil,
what gears does the car have?
Brand new 3.4 accel injectors. The acceleration seems to have smoothed out when I installed the new Bosch o2 christmas eve. I got the other one soldered, but I haven't tried it yet. Then the SES came on 3 times that day. Haven't had it since except for tonight when it came on on the way home. I didnt' have my jumper wire handy, but I'm pretty sure I'll still be getting nothing but 13.

I also haven't tested the closed loop operation since I replaced the o2. It was jumping back and forth before.

The gears are 3.42 I guess. Whatever is stock.
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