[Godzilx]

Car has been lightly making a knocking noise for awhile. Others told me it was most likely lifter tick and nothing to worry about.

Last week I installed a secondary oil cooler and upon driving the car and getting up to temperature, the car developed a droning noise from the engine above 1700rpm. The knocking also got louder. Took a stethoscope to the oil pan and couldn't necessarily make out a definite knock, but without the stethoscope the knocking sounded like it was coming from the oil pan.

https://youtube.com/shorts/J5arK_75Rw4?feature=share

This video starts with the car holding around 1100rpm, then at idle.

https://youtube.com/shorts/I6vpbNGp_oc?feature=share

Video of the droning, kicks in above ~1700rpm

Assumed the noise was rod knock and a bearing had gone bad. Upon draining my oil, it was perfectly clear with no shavings. Intake check valves are also clean. Got a oil analysis kit I am going to send in.

The rods seemed to have to no excessive play upon removing the oil pan as well. Oil pan was also clear of any debris.

Started the car without the accessory belt and the noise is still there.

Do I pull the trigger and replace rod bearings? What else could the noise be? I have an 07 and thought it could be cam bearings but the noise was coming from underneath.

Any thoughts or advice appreciated.

[feuer]

Is secondary oil cooler still installed? If yes removed it. Also, to replicate rod knock best is to rev on and off to about 3000k. I have done many and from your videos can’t tell if there is an issue or not. Anyhow, since you have opened the bottom go ahead and install new bearing.

[Godzilx]

Originally Posted by feuer

Is secondary oil cooler still installed? If yes removed it. Also, to replicate rod knock best is to rev on and off to about 3000k. I have done many and from your videos can't tell if there is an issue or not. Anyhow, since you have opened the bottom go ahead and install new bearing.

Installed the secondary oil cooler for track use. Are you recommending not using it?

When I go to start back up the motor I'm planning on flipping the oil thermostat before cranking the motor so oil can circulate.

[feuer]

Originally Posted by Godzilx

Installed the secondary oil cooler for track use. Are you recommending not using it?

When I go to start back up the motor I'm planning on flipping the oil thermostat before cranking the motor so oil can circulate.

Yes, I have seen this before, engine tapping to be louder after adding aftermarket additional oil cooler. I have been tracking mine for a long time with out .

[whyzee125]

If you've already taken the pan off, then you've got little to lose. You've done the majority of the work so I would go ahead and pull the bearings and replace them. That's a good sign that your oil looks clean.

[Godzilx]

Originally Posted by feuer

Yes, I have seen this before, engine tapping to be louder after adding aftermarket additional oil cooler. I have been tracking mine for a long time with out .

Have you come to any conclusions on what the tapping is or why it's caused?

[feuer]

Originally Posted by Godzilx

Have you come to any conclusions on what the tapping is or why it's caused?

I’m suspecting poor oil flow.

[feuer]

V8TT in trouble. Quality oil and good flow/pressure is a must on these.

[Godzilx]

Originally Posted by feuer

V8TT in trouble. Quality oil and good flow/pressure is a must on these.

Update, took my motor to an N54 specialist to get the rod bearings done. He said the rod bearings didn't look bad enough to cause knock but we replaced them.

Looked at my flywheel and it is somewhat bent. Wondering if this would've caused the knocking noise

The dowel on the crank is quite bent, assuming the flywheel was installed incorrectly when doing the rear main seal which lead the the flywheel bending.

[lonestar22]

Rod knock doesn't usually follow the RPMs that much. It was more than likely coming from the tranny

[feuer]

Originally Posted by Godzilx

Update, took my motor to an N54 specialist to get the rod bearings done. He said the rod bearings didn't look bad enough to cause knock but we replaced them.

Looked at my flywheel and it is somewhat bent. Wondering if this would've caused the knocking noise

The dowel on the crank is quite bent, assuming the flywheel was installed incorrectly when doing the rear main seal which lead the the flywheel bending.

N54 specialist? It didn’t came to me so.....

[luckyblack]

Originally Posted by feuer

N54 specialist? It didn’t came to me so.....

Not to hijack the thread but I have a knocking sound as well coming from the engine bay. I can't replicate it while revving in neutral. My car also feels like its misfiring or skipping at mid to high rpm. I don't have SES or CEL, but the car can't be driven over around 3500rpm without something happening. I've changed coils and plugs. Fuel injectors were supposedly changed a year ago ( i haven't pulled them to verify). Is it possible a fuel injector popped loose? Maybe a bad fuel pump? The car idles great. I realize that I'm not giving you a whole lot of info to go on but any help is appreciated.

[feuer]

Originally Posted by luckyblack

Not to hijack the thread but I have a knocking sound as well coming from the engine bay. I can't replicate it while revving in neutral. My car also feels like its misfiring or skipping at mid to high rpm. I don't have SES or CEL, but the car can't be driven over around 3500rpm without something happening. I've changed coils and plugs. Fuel injectors were supposedly changed a year ago ( i haven't pulled them to verify). Is it possible a fuel injector popped loose? Maybe a bad fuel pump? The car idles great. I realize that I'm not giving you a whole lot of info to go on but any help is appreciated.

Could be a lot of things. It might help if you post a video.

[luckyblack]

Originally Posted by feuer

Could be a lot of things. It might help if you post a video.

https://youtu.be/i-INPqa5Ae4

[luckyblack]

Can anyone else weigh in on this please? I'm not ready to give my car up yet. My local BMW dealer says i have rod knock but I don't believe it. No metal in oil or filter. If I raise rpm up to around 5k ( while driving and let the rpms drop) I don't have any noise at all. I'm getting a bunch of engine skipping around 3k rpm at full throttle. If I bring the rpms up slowly then I don't have the engine skipping issue. I'm starting to think HPFP but no SES or CEL. I have occasional hiccups at idle as well.

[feuer]

Originally Posted by luckyblack

https://youtu.be/i-INPqa5Ae4

Video is too short. Send oil sample for analysis. Also can check for rod knock by pushing piston down. Remove spark plug. Also, you said knock doesn’t start until you drive for a bit. Meaning, need oil to get thinner. So probably is rod knock.

[luckyblack]

Wouldn't knock be heard at idle, neutral revving or high rpm? I only hear it under low rpm load. The car threw SES light today. Cylinder 6 misfire. I put new plug and coil in with no luck. Could a bad injector cause ignition knock by not delivering fuel? Could the knock sensor compensate for a lost Cylinder?

[luckyblack]

I swapped the cylinder 6 injector to 1 and the misfire followed. The knocking noise also sounded different. I'll change the injector and report back but for anyone reading this - i wouldn't rule out a bad injector causing light knock under load while driving. It is an index 12 injector

[Jacob97K]

Originally Posted by Godzilx

Car has been lightly making a knocking noise for awhile. Others told me it was most likely lifter tick and nothing to worry about.

Last week I installed a secondary oil cooler and upon driving the car and getting up to temperature, the car developed a droning noise from the engine above 1700rpm. The knocking also got louder. Took a stethoscope to the oil pan and couldn't necessarily make out a definite knock, but without the stethoscope the knocking sounded like it was coming from the oil pan.

https://youtube.com/shorts/J5arK_75Rw4?feature=share

This video starts with the car holding around 1100rpm, then at idle.

https://youtube.com/shorts/I6vpbNGp_oc?feature=share

Video of the droning, kicks in above ~1700rpm

Assumed the noise was rod knock and a bearing had gone bad. Upon draining my oil, it was perfectly clear with no shavings. Intake check valves are also clean. Got a oil analysis kit I am going to send in.

The rods seemed to have to no excessive play upon removing the oil pan as well. Oil pan was also clear of any debris.

Started the car without the accessory belt and the noise is still there.

Do I pull the trigger and replace rod bearings? What else could the noise be? I have an 07 and thought it could be cam bearings but the noise was coming from underneath.

Any thoughts or advice appreciated.

Crazy, I have the same issue with the whine sound, did you get it sorted out? I have aftermarket cooler aswell.

[Hannesbrodin]

Originally Posted by feuer

Video is too short. Send oil sample for analysis. Also can check for rod knock by pushing piston down. Remove spark plug. Also, you said knock doesn’t start until you drive for a bit. Meaning, need oil to get thinner. So probably is rod knock.

So What can u tell of this video? https://youtu.be/urld1enSH-4 is this rods? Sound more under the car then in front on top of the engine. Also No problems drivning etc. Only some lag while using cruise control

[Kirky87]

I have a n54 2007 stage 2 + (MHD)

Story:

Had the car 8 days.........WOT 100mph+ car misfired and then started what sounded like.rod knock.

Took car to local Indy Shop who deal with this type of thing daily.

ROD bearings where ok but replaced anyway.

Crank been checked ok.

New full set of lifters.

New set of cams.

New Torque Converter.

Refurbished Injectors.

Smoke test clear.

Compression test all good.

Leak down test perfect.

Still have this mysterious noise.

It start upon start up, doesnt go away hot or cold.

Hasn't got worse, bit follows RPM (roughly half engine speed we think)

No metalic bits in oil or filter.

Can anyone help.

With all tye above work done. Car has dome 2500 miles since and has had WOT a few times and no sign of getting worse.

Oil used 5w30

[Tambohamilton]

DMF?