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High knock readings and noise?

22K views 2 replies 2 participants last post by  karellan 
#1 ·
Having Johan look at a log and he says I'm getting lot of knock readings. I'm hearing a little more exhaust rattle noise too. Power seems to get stuck around 4500 rpms.

We were checking the normal questions, good gas, yes 93 and same station as always. Then he asked about metal sounds.

I have a no weeds electric exhaust cutout system on and believed that the clamps weren't tight enough. I have got some small rattle since installed and been meaning to recheck all clamps or just have them finally welded but haven't yet. I guess the overall noise is a little more over the last week or so while I've had this 4200-5000 lack of power spot (it's like a complete lack of power, lower than stock 5.7 hemi acceleration)

I'm going to check obviously but for my knowledge I'm wondering what the range of things I should be thinking about. Can't get to car and under for a few days and am curious/anxious.

Cats going bad? I literally can't think of anything else. No cels

5.7 procharged johan tune, 3.4 pulley, 7psi around 5k, dayco tensioner, stock exhaust manifolds + no weeds, 3200-3600 stall, tranzformer
 
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#2 ·
Do the plugs show signs of detonation?
Knock sensors can be picky on what it "hears". So a exhaust rattle can cause issues.
The lack of power could be from the ecm pulling timing cause of the "knock". I would check everything out. If you cant find anything then disable or lower the sensitivity of the knock sensors.
 
#3 ·
Plugs looked ok when I pulled. I'll post up photos though as I'm not expert on plug reading

Did find one issue. One side of exhaust is completely disconnected before the x pipe in the stock system area. So after the no weeds one clamp is basically off. I'm going to try to get under today to tighten it all back up. If nothing else, that was wrong and maybe had been going wronger and causing issues
 
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