3rd Gear Knock what gives!?!?

[Davepurp]

Weirdest thing hoping you guys might be able to give me a couple ideas that maybe I havent thought of.

Long story short

First installed procharger stage 2 kit and was haunted by false knock, took care of that and everything was peachy.

Fast forward to recent. Installed a boss 302 intake and new FIC1000 injectors DiabloMatt Dialed it in like a champ and fuel trims were great. timing was great. MAF all looked where it should be no complaints other than the recent investment in new boxer shorts cause this thing pulls like its going into orbit in the upper rev range.

I pull logs on occasion on my Diablo Itune 2 and monitor on my ngauge just to make sure everything is ok and it adds timing in 2nd and 4th around town or at WOT but pulls timing in 3rd gear only. Not all the time, but it has been enough now to get me nervous.

Any one have an idea what it could be other than a weird coincidence? My only fear is other than the speed sensors the transmisson is the really the only part of the car that can changes when in different gears so I am really hoping my 3rd gear isnt a ticking time bomb

I attached a few logs to hopefully illustrate what im talking about.

Thanks for the help


Pulls W/ Mak Pipe:
4th gear pull
http://datazap.me/u/davepurp/mak-pipe-boss-302-pulls?log=1&data=11-12-20&mark=507

3rd and 4th gear pull
http://datazap.me/u/davepurp/mak-pipe-boss-302-pulls?log=0&data=12-20


3rd gear Pulls W/ Stock Pipe:

Healthy Pull:
http://datazap.me/u/davepurp/strong-boss-c-tune-pull?log=0&data=12-20

Knock Pulls:
http://datazap.me/u/davepurp/boss-intake-c-tune-pulls-3?log=1&data=12-20

http://datazap.me/u/davepurp/boss-intake-c-tune-pulls-3?log=2&data=12-19-20

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[venumous]

Welcome to my similar nightmare. I had no knock ever and changed to Sai Li with new tune and all the sudden tip in and WOT knock intermittently (while on E85). I too pulled the MAK inlet which seemed like it was working as a fix for a 15 min drive then it returned after a WOT pull went just fine. Ready to pull my hair out. I'm pulling the bumper tomorrow and checking all pulleys, clamps, exhaust etc. What fixed your first issue?

Looks very similar to mine! Stock clutch?

http://datazap.me/u/venumous/sai-li-e85-r3-v2-knock?log=0&data=7-16&trim=0&tmin=24.30&tmax=38.80

 

[Davepurp]

Yup running stock clutch, the first fix was a mix of tightening exhaust claps. Cranking down belt tensioner, and the securing the UPR Catch Can a little more than it already was

 

[diablomatt]

i forgot to ask you is the knock in the middle of the gear or as you are releasing/engaging the clutch?

 

[venumous]

Matt,

Can you compare the two logs and see if you think it could be clutch slip?

 

[Davepurp]

From what I can tell is middle of the gear each time is where Knock is the highest, but it does seem to start at the transition into WOT. is it possible damage prevention or something like that?


Not sure if it helps but I did notice that easing into the throttle with Clutch fully engaged doesnt seem to cause knock

 

[Crackerjack17]

I'm in the same boat, car runs great, but if I change gears too fast it will sometimes pull over 9 degrees! If I immediately let off and back on gas, no knock. I am assuming my long tubes are hitting either steering shaft or frame rail, but does the engine move that much? I cannot find anything loose. I removed the a/c line bolt. I lined all metal surfaces with high temp padding. Next step is to mount crap camera up under there and see if I can catch something moving. Maybe it is the clutch?

 

[venumous]

I'm in the same boat, car runs great, but if I change gears too fast it will sometimes pull over 9 degrees! If I immediately let off and back on gas, no knock. I am assuming my long tubes are hitting either steering shaft or frame rail, but does the engine move that much? I cannot find anything loose. I removed the a/c line bolt. I lined all metal surfaces with high temp padding. Next step is to mount crap camera up under there and see if I can catch something moving. Maybe it is the clutch?

Who is getting a clutch first? I think we have a prime candidate here.

 

[Crackerjack17]

Who is getting a clutch first? I think we have a prime candidate here.

13k on car, 9k with procharger. But a lot of that is straight highway cruising. Clutch "seems" fine, but I did notice a couple weeks ago, I was shifting fast on a highway pull and all of a sudden between gears it felt like I got clutch slip, just for a second. I let off and back on. When it slipped it sounded just for a second like a loud exhaust leak. Maybe it was overheated, but I'm not hard on my clutch except between shifts. Maybe one of the springs are weak or broken? Works great though.

 

[venumous]

13k on car, 9k with procharger. But a lot of that is straight highway cruising. Clutch "seems" fine, but I did notice a couple weeks ago, I was shifting fast on a highway pull and all of a sudden between gears it felt like I got clutch slip, just for a second. I let off and back on. When it slipped it sounded just for a second like a loud exhaust leak. Maybe it was overheated, but I'm not hard on my clutch except between shifts. Maybe one of the springs are weak or broken? Works great though.

Mine seems fine but the car is worthless with this knock.

 

[diablomatt]

Matt,

Can you compare the two logs and see if you think it could be clutch slip?

slip is hard to see unless its doing it a lot. it could be just the slack in thr driveline "clunking"

i will say this, i know for a fact that at 600 wheel if you are to hard on the clutch it will slip. had it happen to me.

dave im gonna send you another tune with more tip in retard to see if that might be triggering it. :cheers:

 

[diablomatt]

Mine seems fine but the car is worthless with this knock.

have you tried cranking down the tensioner? been seeing that A LOT

 

[Davepurp]

have you tried cranking down the tensioner? been seeing that A LOT

This was most likely my first knock issue

 

[Tommy V]

have you tried cranking down the tensioner? been seeing that A LOT

Do u mean the belt tensioner needing tightened up??

 

[Davepurp]

slip is hard to see unless its doing it a lot. it could be just the slack in thr driveline "clunking"

i will say this, i know for a fact that at 600 wheel if you are to hard on the clutch it will slip. had it happen to me.

dave im gonna send you another tune with more tip in retard to see if that might be triggering it. :cheers:

Sounds good to me Ill get it loaded and report back.

To be honest as long as its not my 3rd gear shitting the bed this soon im pretty happy. Clutch I can deal with

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