Question about 1996 Saab 900

2 Answers

I'm hearing a knocking noise from the rear bank on my 95 Saab 900SE (2.5V6). I can't tell if its a hydraulic lifter or a rod bearing. The sound stays in synch with engine rpm's and does not go away after the engine warms up, as I would expect a valve lifter to do. Any ideas on how I should troubleshoot this?

Posted by on

2 Answers

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Top Expert:

    An expert who has finished #1 on the weekly Top 10 Fixya Experts Leaderboard.

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

  • Saab Master
  • 75,797 Answers

Rod or main noise is almost for sure the problem

Posted on Jun 26, 2009

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

Did you ever get this fixed? I'm having the same symptoms

Posted on Nov 11, 2009

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Can lifters be replaced


Oh yea, lifters can be replaced , best if you replace cam an lifters together ! Loud knocking is not usually associated with lifters , they usually make a ticking noise ! Knocking noise is most usually in the bottom of the motor , main or rod bearings . most of the time rod bearings !

Jan 27, 2015 | 1996 GMC Jimmy

1 Answer

2003 deville engine knocks at idle but when u drive knocking goes way down almost cant hear it


The knocking sound that you hear may be coming from lifters, crank bearings or piston slap. How old is the oil change, is there enough oil inside the engine, and is it due? How many miles are on this engine? All of these suggestions are normal with higher mileage vehicles. The only one that doesn't involve rebuilding the motor is the lifters. A lot of times replacing the hydraulic cams will fix lifter noise. I hope this is what you were looking for please write back. If you have any questions, let me know, good luck.

Mar 17, 2014 | Cars & Trucks

1 Answer

Makes knocking noise that sound like something is loos banging only when jeep warms up and only in gear


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.

Dec 07, 2013 | Jeep Cars & Trucks

1 Answer

Making knocking sound


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.

Dec 06, 2013 | Nissan Cars & Trucks

1 Answer

Zx2 noise


It is hard to say for sure without actually hearing it.
A collapsed lifter will make a "tapping" noise closer to the surface on the top end. A rod will make a "knocking" sound that is much deeper. These are your two options. It is either valve train related or a rod, probably a collapsed lifter.
Some people will confuse the two but experience can tell the two apart. So with that said I would have a hard time telling you what exactly it is without hearing it. Hope this helps some.

Jul 07, 2013 | Cars & Trucks

1 Answer

Intermittent noise not a misfire sounds internal like a rod or valve or lifter. No check engine light, car has good power. U only hear noise after car is warm and not all the time. Could it b my belts? Any...


After it's warmed up to operating temp, if it makes the noise at idle but goes away reving the engine, I would guess that a lifter has gone bad. Rod bearings as a rule knock all the time. It's hard to diagnose these things over the internet, because there are so many variables when it comes to noises.

You need to warm the car up and then while it is running, open the hood and try to pinpoint the source. lifter noise will sound like a "tick" and come from somewhere near the top. Rod bearings will sound like a 'knock" and will come from the bottom of the engine.

Jan 25, 2011 | Ford Crown Victoria Cars & Trucks

1 Answer

I have a 1998 GMC Sierra, when I start it in the morning it makes a knocking noise but once it warms up it goes away, what could be causing this?


We really need to know more about what kind of knocking you are hearing.

Pinging, clink clink, sounds like the time you got bad gas and put a strain on the engine causing it to knock. Airflow sensor telling the injectors how rich or lean to mix the fuel. Computer sets fuel air mix. timing , ect to match operating temp and if it is going bad throws the whole thing out of balance.

Ticking... click click click sound from the top of the engine that gradually fades,,( lifters on cam and valve chatter) sticking lifters can be treated with oil additive to clean them out if they aren't stopped up to bad. If that doesn't work or the noise keeps getting louder you need to have someone look at it or you can damage your cam or bend a valve and that can lead to a cascade failure of cam. lifters, valves and possible broken pistons.

Knocking. KNOCK KNOCK knock knock,from the bottom of the engine that fades ( rod bearing worn and slapping the crank til it gets enough oil to float it on the crankshaft or crank bearings worn and bearings trying to spin in the races)
If it is a hard knock could be a worn rod bearing or a partially stopped up oil port in the crankshaft that doesn't let the oil do its thing until it is warmed up. This problem can be slowed down with cleaning additives but the damage has already been done and will do nothing but get worse over time. If it is a bottom end bearing don't let it totally fail. If you have a mechanic you trust get him to listen to it and help you figure out what needs to be done. Once you have heard these noises and have someone point out the differences you don't forget them.
Remember. Sooner you get this figured out the less damage done and the cheaper the repair bill will be.

Jun 12, 2010 | 1998 GMC Sierra

1 Answer

Engine knocking noise in 2000 saab 9-3 SE?


It's a common problem with these cars i am actually fixing mine as of now. That car is all about oil pressure and when it is low you'll start to get a tap and or what sounds like a knock due to the lifters not having enough pressure. Try taking your oil pan off and check your oil pick up line going from the oil pan to the turbo. A lot of times it gets a lot of sludge build up and makes the pressure little to none. If that looks clear check the slump inside the oil pan and see if that has sludge build up. Well hope this helped

Apr 15, 2010 | 2000 Saab 9-3 Viggen

3 Answers

ENGINE KNOCK 81 GMC 1500 (350)


Sounds like a connecting rod bearing problem. I would have a pro. listen to it.

Jan 07, 2009 | 2002 GMC Safari

Not finding what you are looking for?
1996 Saab 900 Logo

Related Topics:

351 people viewed this question

Ask a Question

Usually answered in minutes!

Top Saab Experts

Colin Stickland
Colin Stickland

Level 3 Expert

22114 Answers

yadayada
yadayada

Level 3 Expert

75797 Answers

rgbypoet

Level 2 Expert

166 Answers

Are you a Saab Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...