my wife says it's knocking

[lovetoski]

OK, I didn't pay enough attention to my wife a few months ago when she said the starter was "acting funny" and w/in two days it shorted out, caused a fire, and, well, it was ugly. (Insurance paid for most of it - lucky me.)

She puts 30,000 miles per year on our fzj80, so I need to stay on top of "issues." Heavy empasis on the "preventative" part of maintance. Today she mentioned that it's been knocking. Other than an oil change a week ago, I've done nothing recently. It's never knocked before. Plugs/ignition wires/dist cap/rotor/air filter/pvc were replaced about 8000 miles ago, but no knocking until just a few days ago.

Fuel is Shell or 76, mostly Shell, maybe 76 the last few times (as far as she can remember). The only other variable I can think of is that it's hotter the past few days, here in Seattle - high 80's/low 90's.

She's leaving for a soccer tourny out of town Friday am. Should I ignore this - or are there any recomendations as to a fix to do?

Any suggestions welcome...

 

[Scamper]

Check the timing. Clean the TB and run some injector cleaner thru the system (like BK or Lucas). Try higher octane gas to see if it goes away. Less likely but possible...the knock sensor could be bad.

Edit: PS: always believe your wife on these things...if she's right, you've saved yourself a lot of grief. If she's wrong, then at least you're not toast for not having listened to her

 

[Beowulf]

Doug,

Are you sure she's hearing detonation "knocking" and not some other type of noise. What are you hearing?

-B-

 

[Andrewsreef]

I am still battling some pinging even with 93 Octane gas and new EGR, Modulator and VSV. It is much better but I still get just a little I hear while acclerating moderatly. Usually sounds like one tick or two and I guess the knock sensor is doing its job. I read another post about someone cleaning the throttle body, intake, EGR like mine and a half dozen other things and he still had some pinging also.

I have my timing at factory specs, have done a complete tune up with throttle body cleaning, new plugs and the like.

Good luck.

Andrew

 

[Terrax]

I read another post about someone cleaning the throttle body, intake, EGR like mine and a half dozen other things and he still had some pinging also.

That would of been me, but I'm also running a S/C. I finally resolved my problem this week by installing a Unichip.

 

[lovetoski]

Throttle body is recently cleaned. (Ran stronger afterwords!) She's been driving from one soccer tourny to another, so I've not had a chance to drive it myself. Told her to fill w/89 octane instead of 87 for the time being...

One note - she said the knocking only happened when the A/C was running. And, interestingly, the A/C belt just started squealing at around the same time the knock appeared. The belt had become loose, so I tightened it - squealing gone. Wierd coincidence....not sure if it's related or not.

Will check more when she returns in a few days.

Best Regards,

 

[robbie]

predetonation vs a knock (like piston slap or bearing sounds) are different. I posted some thing a couple of days ago but see it did not get here. But reading the last post I would check the A/C belt to see if it is cracked and some bits are missing. It may be all that is wrong. If not I would take time to listen to the engine and see what is . Both can be devestating to the enigine. The sooner you find the problem the sooner you can correct the problem avoiding more damage if left uncorrected. later robbie

 

[lovetoski]

thanks robbie!

 

[Scamper]

Doug-

Are you sure what you're hearing is knocking? If it only happens when the A/C is on, is it possible that it's related to some square bearing in the AC compressor? Can you hear it at idle with the AC on, and if so, does it come from the engine proper or from the area near the compressor?

 

[acf]

Throttle body is recently cleaned. (Ran stronger afterwords!) She's been driving from one soccer tourny to another, so I've not had a chance to drive it myself. Told her to fill w/89 octane instead of 87 for the time being...

One note - she said the knocking only happened when the A/C was running. And, interestingly, the A/C belt just started squealing at around the same time the knock appeared. The belt had become loose, so I tightened it - squealing gone. Wierd coincidence....not sure if it's related or not.

Will check more when she returns in a few days.

Best Regards,

Is the "squealing" you are hearing more like a fast paced whistling that increases when the compressor kicks in? I have that kind of noise and am trying to pinpoint it. Which belt is the "A/C belt"?