Please Help.. Loud noise while accelerating (1 Viewer)

[hamad974]

Need Help

I have a 1998 Land Cruiser with 250k miles , when accelerating i hear from the right side like my car has a turbo built in. Also i keep getting misfire codes intermittently. Took it to a few mechanics and they suggested the CAT is going bad. Replaced the CAT off a used 100 series and thinking the sound would go away, it didnt. Im really getting frustrated and not sure what else could it be.

Any recommendations would be helpful

Thank you

 

[hamad974]

A 'turbo like' sound makes me think you have an air leak somewhere. Have you inspected the air intake track for cracks or missing hoses? Are your vacuum lines in good shape and not cracked or swelled? When was the starter last replaced, was a new intake manifold gasket used?

I had a mechanic test for air leak and everything came out good. Haven't replaced the starter and no to intake manifold gasket. Ill be posting a video once i upload it to youtube.

 

[94SRUNNER]

Check your spark plugs and coil packs.

 

[Octous]

Did the mechanic use a smoke machine or similar to check for leaks on vac lines and exhaust?

If no they likely didn’t check well enough. It is very hard to find pinhole leaks. And pinholes sometimes sound like turbos. High pitched whistle.

If it only happens under acceleration sounds correlated with engine rocking. If it is at high rpm likely flow related

 

[hamad974]

Check your spark plugs and coil packs.

Changed all the spark plugs and coil packs also ... still getting missfire code but no check engine light

 

[hamad974]

Did the mechanic use a smoke machine or similar to check for leaks on vac lines and exhaust?

If no they likely didn’t check well enough. It is very hard to find pinhole leaks. And pinholes sometimes sound like turbos. High pitched whistle.

If it only happens under acceleration sounds correlated with engine rocking. If it is at high rpm likely flow related

Yeah he used a smoke machine and the noise only happens when im punching it over 50mph and i hear it rumble by the front passenger side under the dash . Its so weird, like really no mechanics are able to pinpoint and i dont to get stuck in replacing everything that mechanics suggest.

 

[hamad974]

 

[hamad974]

Rumble? That description does not match the previous turbo sound description. Passenger side rumble could be a worn u joint or slip joint. In my experience a worn u joint generally makes itself known around 50mph. When was the last time you greased the driveshafts?

Just posted a link to the noise

 

[JunkCrzr89]

You’re at almost 5k RPM

Despite your original claim, the noise appears completely unrelated to speed and entirely correlated with RPMs. Bang the rev limiter and see what happens boiiii

 

[jLB]

Have you looked under your vehicle, to see if someone stole your catalytic converters?

 

[aztoytec]

Is your air filter lid not on all the way???

 

[hamad974]

Have you looked under your vehicle, to see if someone stole your catalytic converters?

Just replaced the Catalytic converters a few weeks ago …

 

[Mike NXP]

Have you looked under your vehicle, to see if someone stole your catalytic converters?

Was thinking that too.

Isn't this noise just exhaust leaking ? Pop the hood and take some pics lets see what we can see.


Is your exhausted rotted out?

 

[Columbo624]

Sounds like an issue with the exhaust side. Reminds me of a bad gasket sound I had in a prior vehicle (non 100).

 

[94SRUNNER]

Sounds like an issue with the exhaust side. Reminds me of a bad gasket sound I had in a prior vehicle (non 100).

Yes. It too reminds me of when I had the flange bolts rust off and the cats separate slightly on an old 94' Toyota pickup I had. Sounded very similar.

 

[hamad974]

You’re at almost 5k RPM

View attachment 3144372

Despite your original claim, the noise appears completely unrelated to speed and entirely correlated with RPMs. Bang the rev limiter and see what happens boiiii

Where is the rev limiter located at ?

 

[Mike NXP]

Where is the rev limiter located at ?

LOL don't hit your red line. With your current exhaust sounding situation it may very well go BOOM.

Inspect your exhaust, starting at the engine and work your way down. That sucker may be rusted out. I'm not sure what else could possibly make that noise but what the heck do I know.

 

[Gnarwgn]

@hamad974 I'm experiencing a very similar issue/sound. Finally found one of the problems, which was that there was a hole in the back vertical panel of my muffler. It was hard to see so took me a few attempts to notice it. Have since replaced the muffler, and the crazy roaring sound (like in your video) is gone but now getting a high pitched whistle from somewhere around the passenger side. Based on comments above sounds like a pinhole leak. I've started working my way back from engine, so far the passenger side header is intact, will share any additional findings!

 

[hamad974]

Now I’m getting these codes even tho i replaced ignition coils and spark plugs.. this is really irritating me

 

[hamad974]

Now I’m getting these codes even tho i replaced ignition coils and spark plugs.. this is really irritating me View attachment 3150904