Ls1 cracked flex plate knock

We used the box end side of a wrench to spread the. Oct 02, 2009 and just to let you know if the flex plate is cracked it will make a knocking sound as well i had a 01 dakota rt and thought that i had blow the motor in it and found one and went and bout it. Loose torque converter bolts and cracked flex plates. It has to be in the tranny area just by the process of elimination. Turns out the flexplate bolts were right up against the starter plate. When a flexplate cracks, it often produces a loud knocking noise as it rotates. Right off the bat, they said it didnt sound like piston slap. Loud knocking sound from torque converter or flywheel posted by kidwiththelaser, oct 17, 2009. Hello all, is the lq4 flex plate and a ls1 flex plate the same. If you have a knocking noise from your engine it might not be the engine itself.

Arp pro series flexplate bolt kits 2442901 free shipping. The flex plate makes a loud knocking noise as it rotates very similar to a bent engine rod. Arp 12 point flexplate bolt kit chev holden commodore ls1 ls2 ls6 2442901. Your system is composed of the highest quality components available. After they checked it out, they said it was a cracked flex plate between the tranny and engine. Almost sounds like rod knock, but i just put the engine in and its been doing it since i first started it up. The ls2 sensors on the other hand, are what is known as a two wire flat response sensor. We used the box end side of a wrench to spread the bushings apart to get them on the sway bar. The sound is very similar to a bad engine rod and is often misdiagnosed. Weve got tough yet affordable flexplates for stock and mildly modified street vehicles. Sep 26, 2016 the big advantage of adding 50 horsepower to the 5. Chevy 168tooth plates have dual bolt patterns to accommodate both powerglide and turbohydramatic th torque converters. It isnt a 512kb ls1 ecm like they went to in 01 for the old school.

The problem turned out to be a cracked flex plate which. Almost sounds like a bentcracked flexplate that you are describing. Proposed the issue was the flex plate rather then the engine. This harness allows the singlewire ls1 knock sensors located on top of the ls1 manifold to be relocated on both sides of the ls2 block and plugged into the factory ls1 pcm harness. The l76 engine had cylinder deactivation technology gms active fuel management, or afm, though the afm system was not enabled when the l76 was first introduced in the holden vz and wl model ranges. Nov 04, 20 this is a loud knock coming from the bell housing of my 2003 trailblazer 4. And brute it home and then pulled the motor and found that the flex plate was cracked in 2 places and that was what was making all the racket. The second problem sounds like something other than knock sensors. Replacing the knock sensors can prevent detonation related engine damage and restore engine performance. A flex plate is used in automatic transmission applications and is used to connect power form the engine to the torque converter of the transmission. Why does my ls1 v8 knock like a diesle engine so much. I was browsing this forum a while ago and stumbled upon a tread or link to a bunch of torque. So finally one guy says check the flexplate and sure enough, 1 bolt was gone and 2 were loose. In fishing around for the source it appears to be loudest coming from from the right wheelhouse.

Ls1 flexplate question hello all, is the lq4 flex plate and a ls1 flex plate the same. Spacer can be removed so the flexplate can used with the early 6. Im swapping in a 411 pcm into a 2000 s10 2wd auto originally had a black box 494 vcm i got the wiring diag from lextech. The ls1 and ls6 use the same powderedmetal, crackedcap rod, which uses a pressedin piston pin. Almost sounds like a bent cracked flexplate that you are describing. These premiumgrade arp pro series flexplate bolts are far superior to oem hardware. The turn key 510 ls2 uses a combination of stock and custom internal parts. After they checked it out, they said it was a cracked flex plate between the tranny and engine, and that this is a known issue with gm. Loud knocking sound from torque converter or flywheel. Racetronix ls1 to ls2 knock sensor retrofit harness.

The classic and most obvious symptom of a cracked flexplate involves the sound it makes while the engine is running. Those factors ensure that when the engine starts and the driver puts it in. I grabbed 2002 gmc sonoma 4x2 truck automatic l35 4. As maskin said, all cams flex a little and its no big deal, but in the ls the cam and crank are like noodles in there, and it wipes out bearings and lifters.

Demonstration of broken flexplate causing no start condition. Exhaust rattle check the down pipe, tail pipes, and have engine tie down strap 4. Track day in the e55 and bonus race on the way home. It fits fine but the snout is all the way in and the flex plate is about 14 to 516s away from the plate i have and. Any damage to the vehicle or injury resulting from usage of these materials is 100% the. All specs are taken from helmsgm documentation for a 2000 model fbody. When a flex plate fails it usually cracks at the crankshaft mounting bolts. In this video i talk about a noise coming between the engine and transmission. I am now leaning towards a flex plate, it does have an aftermarket converter so those nuts have been removed before. Stock power is 390400 hp, but turn key replace the cam, pistons, rod bolts and valve springs, add a custom 90mm throttlebody and billet aluminum fuel rails, and work a little custom tuning calibration magic to produce a package that is conservatively rated at 510hp. Either loose bolts on the flex plate or a cracked flex plate or bad torque converter. If it did not started till after the tranny replace it has to be in that area. Other than using a stethoscope or a long extension placed on the block at various cylinder locations and listening for the small differences in noise i cant help you much on the lifter noise.

How to know if a flexplate is warped it still runs. Side mount knock sensor adapter harness ls1 gen iii to ls2. Racetronix ls1 ls2 knock sensor relocation harness. Mrc magnum holden commodore vp vr v6 flex plate flexplate. Compatible with the pcm harness in ls1 corvette and fbody. Ive read about an oil filter solution and i heard of a cracked flex plate. Michigan motorsports ls1 flexplate adapter spacer fits gm th350 th400. This flexplate will allow your ls1 series engine bolt up to a 4l80e or th400 with the standard 11. Compatible with the pcm harness in ls1 corvette and fbody cars.

Discussion in engine topic started by purple81, may 10, 2006. A loose bolt on a flexplate or a crack between the bolt holes can result in the same knocking or. The reason for the sound involves the flexplates location and its function. A rattling noise the behind engine loose flywheel bolts. Im thinking about unbolting the torque converter and seeing what that does. Sep 26, 2017 use a flex plate holding tool once you have the bolts initially snug so you can bring the bolts to final torque of 85 lbft. Code would be helpful otherwise were just stabbing in the dark. Kit instructions opens in a new window the prices listed on this website are for estimating purposes only. Use a flex plate holding tool once you have the bolts initially snug so you can bring the bolts to final torque of 85 lbft. When you hit the right cylinder with the bad rod bearing the sound will quit or get much.

If its a rod knock, you can make the sound change or go away by pulling off each plug wire one at a time. May 27, 20 you can isolate a broken flex plate by bringing the rpms up to about 1800 and keep it steady. Side mount knock sensor adapter harness ls1 gen iii to. I had my precision stall converter re stalled and they made the motor side snout a little longer so it would bolt up the a ls motor. Did a winter start of my 3800 a week ago and was greeted with a whirringfast tapping sound. I have seen incorrect flex plates installed for the. All content provided on this site is to be used as a suggestion only. Vehicles with the engine knock problem include 1999 2002 gmc and chevy pickups and sportsutility models with 3. A lifter can sound like knock as can a bad exhaust leak in the right spot. A cracked flex plate is usually a sign of other problems.

This adapter harness will allow you to use an gen iii style ls1 or truck harness while relocating the knock sensors from underneath the intake manifold to the sides of the block. And we also have heavyduty and sfiapproved flexplates for highhorsepower, highrpm race applications. This harness only works with single wire gen iii knock sensors, not the gen iv style. This item prw 1834610 xtreme duty sfirated internal balance 168 teeth steel flexplate for gm ls1, ls2, and ls6 1997present prw 1835001 sfirated internal balance 168 teeth chromoly steel flexplate for chevy 195785, 90 early, v6, gold irridate. There are tough flexplatesand there are chuck norriscaliber flexplates. If it is the flex plate could be cracked and that too can sound like a rod knock. This is a loud knock coming from the bell housing of my 2003 trailblazer 4. False knock, or so it seems page 2 turbo buick forum. If the flex plate is cracked, there will be one solid knock sound when you turn the key back on. Other than using a stethoscope or a long extension placed on the block at various cylinder locations and listening for the small differences in noise i. It has the perfect added length and thermal protection required to be routed near hot exhaust manifolds. A cracked flex plate will often make a popping noise or a tinny sound when running. The ls1 kss are a single wire broadband sensor that the pcm sends a certain amount of voltage to, as the sensor detects knock, it changes the voltage reading and the pcm then knows how much knock is present by the amount of feedback voltage change.

Descriptions of the sound include clanking, chirping and a light knocking. I bought a mechanics stethascope and listened for a knocking sound. If you replace the flex plate and dont fix the real problem your flex plate will most likely. To install the cam, youll just need to pull the valve covers, loosen the rockers, and disassemble the front of the engine as previously shown on the 6. Its bad enough that i am deaf, but a deaf guy trying to find an obvious knock is like a blind guy trying to find the same chick in a crowded whorehouse on payday. Here at advance auto parts, we work with only top reliable flywheelflexplate product and part brands so you can shop with complete confidence. A loose wrist pin can cause a rod knock like sound, so can excessive piston slap or a colasped piston skirt. I double checked the wiring, before doing a fullflash. Happened in my 348 3x2 hooked up to an aluminum pg. Still trying to narrow down the problem and believe that it might be the harmonic balancer, the oil pump or in. The sound seemed to be coming from the area between the motor and. This is a discussion on torque spec sheet within the camaro ss forums, part of the vehicle specific category. I have seen incorrect flex plates installed for the engine.

Then slide the bushings onto the sway bar back to the same place where the stock ones are on the factory sway bar with the slits facing the rear. The official arp web site kits arp the official web site. When it comes to your gmc k1500, you want parts and products from only trusted brands. The problem turned out to be a cracked flex plate which is much cheaper than rebuilding or replacing the engine. Mine was cracked all the way around the center mounting holes shop the new. Normal and usually caused by the starter engaging the flex plate. Special thanks to crackeregg for making these documents available in a digital format saved me a lot of typing. This will make little to no noise at idle and make more noise depending on how much load the engine is under. Place a little grease should come with the bushings inside the d bushings. The tci 399753 flexplate fits 1998 and newer fbodies with ls1 engine as well as 99 and newer gm trucks with 4. The car and truck powderedmetal rods can handle over 500 hp. Forged from aerospace alloy and heattreated prior to thread rolling and machining, they feature an exclusive, flat 12point head design and a largerthanstock shank diameter for increased strength and. It can also cause a starter to act funny when starting the car.

Need help with finding engine knock lightning rodder. I have seen on occasion the torque converter bolts get loose and. Broken or loose bolts on the crankshaft end of the flexplate, or on the torque. And just to let you know if the flex plate is cracked it will make a knocking sound as well i had a 01 dakota rt and thought that i had blow the motor in it and found one and went and bout it. Its a fairly common prob especially if you wash the engine alot. It should provide many miles of troublefree performance when used correctly. Could it be in the bell housing from the torque converter or flexi plate cracked or nuts loose or gearbox oil pump. Faulty knock sensors will typically trigger a check engine light and prevent your engine from running at its best. Loose flywheel or flexplate bolts make a rattling or knocking sound that. Outside the united states, the prices may be higher due to transportation costs and import duties. It may be as easy as removing a small torque converter cover or it may. It was finally put in my car and started maybe 11 months later to find out i had a rod knocking.

If my car ran low on oil and now there is a knocking sound. The tci superquality flexplates are thicker than stock plates to withstand the stresses of todays high rpm engines and highstall torque converters. I think my ls1 wont get replaced after all, and i should seriously start looking into doing this repair myself. Dec 28, 2004 right off the bat, they said it didnt sound like piston slap. Congratulations on purchasing your nos nitrous oxide injection system. In our quest for horsepower, we ordered a trick flow sfiapproved harmonic dampener, which is designed to be 25 percent under driven to free up more horsepower. The big advantage of adding 50 horsepower to the 5. I really hope thats what it is, and that the noise will go away when replaced.