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bigcity25
01-17-2012, 12:39 PM
So since I have had this 40 it's had this weird chirping noise that comes from somewhere around the intake exhaust manifold. I can't make it happen it just does when it wants to. Sometimes after driving on the highway or just around town. I want to think it's my heat riser valve but I am not totally sure. BTW I have a 7/70 fj40 with a mostly desmogged 2f. Here's a link to a video I took, the noise will happen when I press the gas pedal.
http://www.youtube.com/watch?v=HofrZCGN0wE&context=C32fa300ADOEgsToPDskLdNNyUc6AV6TyPG49LZRld[/URL][/URL]

Tell me what you think, I have searched high and low for something that looks like it's loose and haven't found squat.

corsair23
01-17-2012, 12:48 PM
Exhaust leak?

HofrZCGN0wE

PhatFJ
01-17-2012, 01:19 PM
[QUOTE=corsair23;200970]Exhaust leak?

That would be my guess also..

bigcity25
01-17-2012, 01:20 PM
Maybe, exhaust is new from the manifold back. I bet it's the oem gasket. But there's a distinct metal rattle. I wonder if that heat riser flap is busted. And if it is, I wonder if that affects my mileage also. Btw thanks for posting that video. I am not real computer savy.

TIMZTOY
01-17-2012, 06:44 PM
exhaust for sure.. possible cat

bigcity25
01-17-2012, 06:56 PM
"cat" you lost me there

bigcity25
01-17-2012, 07:09 PM
http://www.youtube.com/watch?v=xEcpEKEsh4Q[/URL]

http://www.youtube.com/watch?v=pKAWV-m0axw[/URL]

You can kind of hear the rattle at the beginning of the first video and at the beginning and end of the second.

I agree there's something with the exhaust. Just can't make it happen and pinpoint when it does and doesn't happen.

RockRunner
01-17-2012, 11:37 PM
"cat" you lost me there

I think he means you ran over a cat :rolleyes:

corsair23
01-17-2012, 11:40 PM
http://www.youtube.com/watch?v=xEcpEKEsh4Q

http://www.youtube.com/watch?v=pKAWV-m0axw

You can kind of hear the rattle at the beginning of the first video and at the beginning and end of the second.

I agree there's something with the exhaust. Just can't make it happen and pinpoint when it does and doesn't happen.

:thumb:

Maybe a shield or something rattling?

To imbed your YouTube links, put the part in bold above in the YouTube wrap - you won't see the icon for YouTube in a quick reply section but you do see it if you click on "Post Reply"...or just wrap "{YOUTUBE} {/YOUTUBE}" this around the bolded parts...except use the brackets [ and ] vs. { and }

xEcpEKEsh4Q

pKAWV-m0axw

subzali
01-18-2012, 08:20 AM
Your FJ40 doesn't have a "cat" - catalytic converter - that's a '79 and later thing.

It sounds like it could be precombustion (also called "pinging") to me - what's your timing set at? If it is an exhaust leak, with it being that big and noticeable you should be able to feel puffs of exhaust while it's running if you move your hand around the exhaust manifold area. Or you will be able to see a black sooty area where it's leaking. You could also take a squirt bottle with soapy water in it and see if you can make bubbles appear somewhere...

In your hood-up videos, it looks like you have a Weber on there? It is making significant noise as you're blipping the throttle - maybe there's something loose inside it?

TIMZTOY
01-18-2012, 06:53 PM
didnt know it didnt have a cat.. i just listened to the first 10 seconds of the video. and the noise is typically what a bad cat sound like

baja1d
01-18-2012, 10:01 PM
I've got a timing light, your tranny bolts, and I just put in a garage heater.

bigcity25
01-18-2012, 10:13 PM
1. Yeah it's a weber and had the noise before when I had a stock carb.
2. I have looked for soot and also exhaust puffs and haven't felt anything.
3. Not sure what my timing is but my mileage is bad
4. Ill take up anybodies help on my timing and carb adjustment. Been meaning to meet with Jeff Zepp up in the hills. But haven't had the time to get up there yet.


Just drives me nuts because it's so random and can't make it happen.

subzali
01-19-2012, 08:07 AM
What kind of Weber is it? Webers aren't known for giving you good gas mileage...

bigcity25
01-19-2012, 04:13 PM
I believe its a 38mm, thinking that sounds right.