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sounds like a bad rod bearing. if auto trans put in drive hold brake firmly with left foot gently push on gas pedal with right foot if knocking increases with engine rpms bad rod bearing time for engine rebuild
TROUBLESHOOTING ENGINE NOISES
A KNOCKING SOUND IN THE ENGINE IS MOST LIKELY CAUSED BY ONE OF THE FOLLOWING
1. PISTON SLAP: Makes a sharp metallic noise. Idle engine and short out each cylinder plug. The noise will disappear when plug with bad piston is shorted. Noise will also disappear at acceleration. This can be caused by worn or out of round cylinder, or broken piston ring. Correct problem by re-boring cylinder and/or replacing piston.
2. VALVE NOISE: Makes clicking or rattle noise. Caused by excessive wear on valve stem or lifter, out of adjustment, or stuck valve. Correct by adjusting valve clearance, replace worn valve or lifter, regrind cam, replace valve guide and /or valve. A stuck valve can sometimes be loosened by passing oil through the carburetor while engine is running.
3. ROD BEARING KNOCK: Makes sharp metallic noise similar to a piston slap. Detection is opposite of piston slap. Rod knock is not heard at idle. Knock becomes louder as engine speed is increased. Caused by excessive rod bearing clearance. Correct by adjusting rod bearing clearance to .0015 inches by removing shims. May require re-pouring rod bearing.
4. REAR MAIN BEARING KNOCK: Makes dull knocking or thud noise. Detected at speeds between 20 and 50 MPH. Knock will normally decrease or disappear while pulling or decelerating. Noise will be detected the loudest at normal driving speed, when not pulling or decelerating. Correct by adjusting bearing clearance to .001 to .0015 inches. If knock is excessive, crank should be checked for out of roundness. May need to re-pour all main bearings to correct.
5. TIMING GEAR KNOCK: usually the most difficult to diagnose. If gear is loose or badly worn it will knock in all ranges. Run engine slightly above idle speed. Slowly open and close throttle. Knock will continue to be present, but just as engine slows down knock will become a slight rattle. Remove timing pin and reinsert into timing hole on timing gear cover. Press timing pin tightly against timing gear and accelerate slightly above idle. Knock will significantly be reduced or disappear. Correct by replacing both timing gear and crank gear as a matched set. The two gears should have a backlash clearance of .003 to .004. If more than .009 inch backlash, an oversize (.005) timing gear should be installed.
6. WRIST PIN SLAP: This can not be detected by shorting out the cylinder plugs. Rapidly accelerate and decelerate the engine speed. The engine will pass through a certain speed range when the wrist pin will rattle at about the same pitch as a valve tappet noise. This can be corrected by installing a new wrist pin bushing in the rod or new wrist pin f badly worn. Wrist pin should fit the piston and connecting rod with a tight metal to metal fit. The pin can be pushed into the piston and rod with a slight pressure of the hand. Pin to rod clearance is .0003 to .0005 inches.
A KNOCKING SOUND IN THE ENGINE IS MOST LIKELY CAUSED BY ONE OF THE FOLLOWING
1. PISTON SLAP: Makes a sharp metallic noise. Idle engine and short out each cylinder plug. The noise will disappear when plug with bad piston is shorted. Noise will also disappear at acceleration. This can be caused by worn or out of round cylinder, or broken piston ring. Correct problem by re-boring cylinder and/or replacing piston.
2. VALVE NOISE: Makes clicking or rattle noise. Caused by excessive wear on valve stem or lifter, out of adjustment, or stuck valve. Correct by adjusting valve clearance, replace worn valve or lifter, regrind cam, replace valve guide and /or valve. A stuck valve can sometimes be loosened by passing oil through the carburetor while engine is running.
3. ROD BEARING KNOCK: Makes sharp metallic noise similar to a piston slap. Detection is opposite of piston slap. Rod knock is not heard at idle. Knock becomes louder as engine speed is increased. Caused by excessive rod bearing clearance. Correct by adjusting rod bearing clearance to .0015 inches by removing shims. May require re-pouring rod bearing.
4. REAR MAIN BEARING KNOCK: Makes dull knocking or thud noise. Detected at speeds between 20 and 50 MPH. Knock will normally decrease or disappear while pulling or decelerating. Noise will be detected the loudest at normal driving speed, when not pulling or decelerating. Correct by adjusting bearing clearance to .001 to .0015 inches. If knock is excessive, crank should be checked for out of roundness. May need to re-pour all main bearings to correct.
5. TIMING GEAR KNOCK: usually the most difficult to diagnose. If gear is loose or badly worn it will knock in all ranges. Run engine slightly above idle speed. Slowly open and close throttle. Knock will continue to be present, but just as engine slows down knock will become a slight rattle. Remove timing pin and reinsert into timing hole on timing gear cover. Press timing pin tightly against timing gear and accelerate slightly above idle. Knock will significantly be reduced or disappear. Correct by replacing both timing gear and crank gear as a matched set. The two gears should have a backlash clearance of .003 to .004. If more than .009 inch backlash, an oversize (.005) timing gear should be installed.
6. WRIST PIN SLAP: This can not be detected by shorting out the cylinder plugs. Rapidly accelerate and decelerate the engine speed. The engine will pass through a certain speed range when the wrist pin will rattle at about the same pitch as a valve tappet noise. This can be corrected by installing a new wrist pin bushing in the rod or new wrist pin f badly worn. Wrist pin should fit the piston and connecting rod with a tight metal to metal fit. The pin can be pushed into the piston and rod with a slight pressure of the hand. Pin to rod clearance is .0003 to .0005 inches.
A KNOCKING SOUND IN THE ENGINE IS MOST LIKELY CAUSED BY ONE OF THE FOLLOWING
1. PISTON SLAP: Makes a sharp metallic noise. Idle engine and short out each cylinder plug. The noise will disappear when plug with bad piston is shorted. Noise will also disappear at acceleration. This can be caused by worn or out of round cylinder, or broken piston ring. Correct problem by re-boring cylinder and/or replacing piston.
2. VALVE NOISE: Makes clicking or rattle noise. Caused by excessive wear on valve stem or lifter, out of adjustment, or stuck valve. Correct by adjusting valve clearance, replace worn valve or lifter, regrind cam, replace valve guide and /or valve. A stuck valve can sometimes be loosened by passing oil through the carburetor while engine is running.
3. ROD BEARING KNOCK: Makes sharp metallic noise similar to a piston slap. Detection is opposite of piston slap. Rod knock is not heard at idle. Knock becomes louder as engine speed is increased. Caused by excessive rod bearing clearance. Correct by adjusting rod bearing clearance to .0015 inches by removing shims. May require re-pouring rod bearing.
4. REAR MAIN BEARING KNOCK: Makes dull knocking or thud noise. Detected at speeds between 20 and 50 MPH. Knock will normally decrease or disappear while pulling or decelerating. Noise will be detected the loudest at normal driving speed, when not pulling or decelerating. Correct by adjusting bearing clearance to .001 to .0015 inches. If knock is excessive, crank should be checked for out of roundness. May need to re-pour all main bearings to correct.
5. TIMING GEAR KNOCK: usually the most difficult to diagnose. If gear is loose or badly worn it will knock in all ranges. Run engine slightly above idle speed. Slowly open and close throttle. Knock will continue to be present, but just as engine slows down knock will become a slight rattle. Remove timing pin and reinsert into timing hole on timing gear cover. Press timing pin tightly against timing gear and accelerate slightly above idle. Knock will significantly be reduced or disappear. Correct by replacing both timing gear and crank gear as a matched set. The two gears should have a backlash clearance of .003 to .004. If more than .009 inch backlash, an oversize (.005) timing gear should be installed.
6. WRIST PIN SLAP: This can not be detected by shorting out the cylinder plugs. Rapidly accelerate and decelerate the engine speed. The engine will pass through a certain speed range when the wrist pin will rattle at about the same pitch as a valve tappet noise. This can be corrected by installing a new wrist pin bushing in the rod or new wrist pin f badly worn. Wrist pin should fit the piston and connecting rod with a tight metal to metal fit. The pin can be pushed into the piston and rod with a slight pressure of the hand. Pin to rod clearance is .0003 to .0005 inches.
If you have a knock, then you have a bad rod bearing. If you have a tick, then you have a bad lifter or an out of adjustment rocker arm. One way to see what clyinder it is, is to have the engine warm and running. Then one by one remove a plug wire from a cylinder. Replace the wire and go to the next one and you should be able to hear a difference in the knocking. This will tell you which rod bearing is the issue. The best way is to take off the oil pan and give each rod cap a tap with a hammer. If you have a bad rod, it will have a hollow sound and the good ones will sound solid. I hope this helps.
any codes would show if sensor bad or going bad a rod knock is internal lower engine problem(connecting rod) rod knock can b bearing -rod-pin -piston harmonic balancer is on crankshaft out side of block if bad usually breaks off or causes heavy vibration
I believe there is a knock sensor on this engine causing it not to run. If the knock is too bad it wont run....It actually probably saved your engine....find out why the knock...out of timing?...clogged fuel filter? bad gas? thrown rod?
You will have to pull the engine and remove the crank shaft and connecting rods you have a bad rod bearing. I will strongly suggest taking to a machine shop and having the crankshaft turned and the rods resized. This will be no minor undertaking and will require time to repair. You could also look into purchasing a rebuilt engine.
2 things that this SUV are known foe Rod knocks and bad tranny.. both very $$$$$ but they are great when they are working right.... Rod knocks are very VERY bad
I listed it but didn't show, 93 olds cutlass supreme mpfi 3.1L LHO engine
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