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Author Topic: FiTech install, now engine is knocking, it never ends......  (Read 805 times)

Online Katfish

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FiTech install, now engine is knocking, it never ends......
« on: June 04, 2017 - 08:02:00 pm »
 Is this "rod knock"? I'm just finishing up my FiTech install, and this is what I hear at idle.

I disconnected 1 plug wire at a time to see if I could isolate it, no change at all. Sounded just the same or worse.

The "noise" does go away when the throttle is opened up even a little. Noise only seems to occur at idle.

What are the odds that this happens with the fuel injection conversion?

https://youtu.be/cxK9yT6MpPE

I pulled the inspection cover on the tranny to make sure it wasn't a loose bolt hitting the block.
All 4 TC bolt heads are clean.

Any ideas?




Offline jhaag

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Re: FiTech install, now engine is knocking, it never ends......
« Reply #1 on: June 04, 2017 - 09:28:05 pm »
could that be a low speed misfire you are hearing out of the exhaust? maybe lean? rod knock would not go away when raising rpm.  :dunno:
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Offline 734406pk

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Re: FiTech install, now engine is knocking, it never ends......
« Reply #2 on: June 04, 2017 - 09:37:47 pm »
Noises like this can be tough to find! My first thought is torque converter to flex plate bolts. I would suggest taking the vee belts off and try to localize where this noise is coming from. It doesn't sound like a rod knock though. What is your hot idle oil pressure?
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive


Offline gyman98

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Re: FiTech install, now engine is knocking, it never ends......
« Reply #3 on: June 05, 2017 - 10:24:17 am »
Are you using the timing control?  If not do you have it set to tach? What is your A/F ratio when the knock can be heard? Also phone fitech tech support they are very helpful
1970 hemicuda convertible clone 426/727 3.23 8 3/4 suregrip

Online 1 Wild R/T

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Re: FiTech install, now engine is knocking, it never ends......
« Reply #4 on: June 05, 2017 - 11:08:04 am »
Are you using the timing control?  If not do you have it set to tach? What is your A/F ratio when the knock can be heard? Also phone fitech tech support they are very helpful

Has nothing to do with FiTech, have you seen the photos?  Put a flex plate on it period....
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Offline cudabob496

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Re: FiTech install, now engine is knocking, it never ends......
« Reply #5 on: June 05, 2017 - 01:18:25 pm »
something under distributor cap?
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.
Up to 4000 RPM, Warp Speed, Up to 5000, Rediculous Speed, Up to 6000 RPM, Ludicrous Speed!

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

Offline Chryco Psycho

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Re: FiTech install, now engine is knocking, it never ends......
« Reply #6 on: June 05, 2017 - 06:46:40 pm »
What about the fuel pump pushrod , did you remove that

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Offline 734406pk

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Re: FiTech install, now engine is knocking, it never ends......
« Reply #7 on: June 06, 2017 - 08:33:37 pm »
The more I listen to the Youtube video, the more it sounds like the torque converter is loose/rattling on the flex plate.  :dunno:
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline Deadeye74X2

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Re: FiTech install, now engine is knocking, it never ends......
« Reply #8 on: June 06, 2017 - 08:40:28 pm »
Blown exhaust manifold gasket?? Do you hear it on the other side as well??

Online brads70

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Re: FiTech install, now engine is knocking, it never ends......
« Reply #9 on: June 06, 2017 - 10:27:33 pm »
 :clueless:  Doesn't sound like rod knock to me? First thoughts were exhaust pipe rattling on something, broken or loose motor mount?
Brad
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Offline 7212Mopar

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Re: FiTech install, now engine is knocking, it never ends......
« Reply #10 on: June 07, 2017 - 01:05:54 am »
 I vote for broken motor mount.
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Offline cudabob496

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Re: FiTech install, now engine is knocking, it never ends......
« Reply #11 on: June 07, 2017 - 02:41:55 am »
something loose under a valve cover?
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.
Up to 4000 RPM, Warp Speed, Up to 5000, Rediculous Speed, Up to 6000 RPM, Ludicrous Speed!

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

Online Katfish

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Re: FiTech install, now engine is knocking, it never ends......
« Reply #12 on: June 13, 2017 - 09:37:48 pm »
Those who said torque converter bolts were right, they had come loose and where letting the TC slap around on the flex plate.
Seems weird that all 4 would come loose.

Offline 734406pk

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Re: FiTech install, now engine is knocking, it never ends......
« Reply #13 on: June 13, 2017 - 10:10:09 pm »
Glad it was something simple! Maybe put some 242 Loctite on them and re-torque.
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline jhaag

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Re: FiTech install, now engine is knocking, it never ends......
« Reply #14 on: June 13, 2017 - 10:39:30 pm »
Hmmm...original post said those bolts were checked and ok? Oh well glad you figured it out!  :thumbsup:
love 70 Challengers