Engine "dieseling" nosie

[jranger35]

Hello all. I would appreciate any input you all have on this one.

My 98 Limited started making a "dieseling" pulsating sound from the front of the block. I immediately thought fan clutch, but that wasn't it. I then checked the valves (screwdriver method), they sounded good. Next I checked the top timing belt idler pulley with the engine running--it was good too. Since the noise was lower on the block, near the crank pully, I thought it must be the lower timing belt pulley. My mechanic friend agreed. Well, I stripped her down, replaced the timing belt and the pulley, put her all back together, and it's still making the same sound. I'm out of ideas. The noise is getting louder and worse now, and I'm afraid something is going to break on me. The water pump is not leaking, so I don't think it's that bearing that is going. Anybody had this problem before?

Thanks!!

 

[riceandpho]

could be a spark plug not sparkin

 

[RunnerUp]

ok... i might have the same noise, could it also be described as a ticking noise? whenever i slow down at a stop light a tick starts to happen and i havent been able to locate it yet...

 

[jranger35]

There's a little bit of "tick" in there, but mostly it's a pulsating dieseling noise. I'm going to take the drive belts off and run it for a little bit to see if that will help locate the problem.

 

[RunnerUp]

i wish i could figure out how to host a video so i could show you/allow you to listen where my noise is coming from so we can combine attempted fixes and work from there if we have the same issue, do you have the 3.4L?

 

[jranger35]

Sure do. It's right at 100,000 miles.

 

[RunnerUp]

thats funny, because im at 97700 right now, so perhaps it is the same noise...

 

[marko3xl3]

http://www.marko3xl3.com/sounds/engine_tick_1.wav
http://www.marko3xl3.com/sounds/engine_tick_2.wav

Is it the same noise as above?

Yes, I have the 3.4L.

 

[jranger35]

No, but that's pretty cool.

My noise is not at regular intervals. It's not click-click-click in time with the engine. I hear those noises and I think valves or rocker arms. It's more like whiRRRrrr-whirrrRRRRRRRRrrrr-whirrrRRrr-whirRRRRrrr.

 

[RunnerUp]

marko... that sounds like mine, im going to start a new thread for that noise, and will label it Toyota Engine Tick as to not hijack jranger35's thread...

as for that noise... have you checked your airbox and elbow? its just a thought, perhaps the throttle body is malfunctioning?

 

[trd_style]

i think the "whiRRRrrr-whirrrRRRRRRRRrrrr-whirrrRRrr-whirRRRRrrr" is normal usually when i start the car, it makes that mid-loud noise for awhile. after i'm driving for few minutes. it was gone. probably just starting the car.

and i don't think it has to do with the intake. because there's nothing cranking from the intake to make that type of clicking sound. it has to do with the fan though. even though as stated, it wasn't. maybe the cams has to do with it? you can look into that.

 

[whomhead]

Use your screwdriver method on your fuel rail. I may be misunderstanding what you're describing, but I have a "diesel" sound to my engine as well after reassembly. A stethoscope revealed that it was the #1 fuel injector. Sounds an AWFUL lot like valve train noise, but it isnt.

 

[marko3xl3]

If it's not a noise that's synchronized with the engine, it could be the cabin fan, have you checked that?

 

[jranger35]

Yeah, I've got an old honda civic that makes that noise inside the cabin when the fans are on high. The 4runner isn't doing that. I wish it was though.