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Need some help with logs/knock please.


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Car is running a OTS map from Matt Miner.

Has a SPT cold air, GMS cat back, CNT high flow catted downpipe. That's it for tune mods.

Hey all, have not posted on here in a while. Around a year and a half ago I bought a 09 LGT MT. Come to find out a month or two later the motor was no good, I was also getting consistent knock when going up hills? bad compression around most cyl with 4 being the worst (60 psi). Luckily I found a motor at my job where I went in blind with a leak down tester (didnt know what i was doing. ) But according to the directions the motor passed the leak down test. Fast forward today, I've put the "new" motor in. I did a cold compression test after driving it for about a week. All plugs out, with throttle down and the lowest cylinder being 113, the highest being 118. 

I still have been having this consistent issue that I was having with the last motor. My feedback knock will jump around when I am going up hills.. It happens A LOT in 3rd gear as well, at full throttle going uphill. Rarely does it happen when I am on a straight or down hill (sometimes it happens in higher RPMs third gear?).  I do not see knock in 1st or 2nd gear at full throttle ever.

Today my dam dropped to .75 and back up to .875 a few seconds later. 

The car has pulled great, it idles relatively well. Sounds like an average boxer. Haven't heard any audible knocks. I put group n motor mounts in, did almost all the gaskets on the motor. 

I genuinely do not know if the motor is junk and my warranty is going to end soon.  (id assume my work would help me out but better safe than sorry.) I have been consistently trying to find the problem, with motor mounts. loose things under the hood, vacuum leaks, pcv. I have zip tied everything. I also feel like most of the 3rd gear knock happens around 80 mph. The car has an AWFUL power steering rack, and a god awful alignment. At above 75 the wheel will be shaking pretty rough. The rack I have not replaced as I don't want to invest much more till I know it is worth it.

I'm going to leave some logs, but bare with me I have never put logs up before and don't know if I was supposed to shorten anything. Sorry for this being all over the place.

 

-2.8 knock (the most consistent one ive seen, usually stays while im on the throttle going up hill.)

https://docs.google.com/spreadsheets/d/16bs1JwTqoGBow7gGi0PNE0p_rv37CO_Fj1t0CR0YGl0/edit?usp=sharing

1-3 pull with slight knock in 3rd gear.

https://docs.google.com/spreadsheets/d/1Ozy2kIIK8I8E-_zdG5xLI3-MTyDWyOiUBVEMrksqQz4/edit?usp=sharing

-4.2 knock

https://docs.google.com/spreadsheets/d/1y2_wA-eX3Y6vOvX6XkS5l3fD59BRnw44jwmsYd3DQY4/edit?usp=sharing

-3.15 knock

https://docs.google.com/spreadsheets/d/1TwQpneo1NiWdtqu5fl6eX8b6Tqzaeo5Krf16gfVpnKI/edit?usp=sharing

no knock 3rd gear. likely on a straight

https://docs.google.com/spreadsheets/d/17NPLghW9-dUFNZaCPtHcMnwVXzIDyyHZDP_BoVxyF_4/edit?usp=sharing

log i noticed my dam was done(if i noticed i would not have gone into boost ;( )

https://docs.google.com/spreadsheets/d/1XdHWXwtEWi5wbowMsEa9UyLbRNYuBpFEjoSLjfkh_uY/edit?usp=sharing

 

Edited by prezton
link, correcting number
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Have you done a smoke test to see any vacuum leaks ?

Is the MAF sensor clean ? spray it with MAF Cleaner.

I'm not good with Log's, hopefully one of the experts will chime in soon.

 

 

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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