Hi all so I have a slight issue that I cannot pin point.

So the other day I re tensioned my timing belt on my b20 because it was kinda tight.
So I did it according to manual.
Now I have this weird flapping or a knock noise from about 3 - 4.5k rpm and cannot figure what the noise is. I thought maybe it was something rattling in the engine bay but I’ve tried everything.
heres a lil more info;

it doesn’t make the noise if reved in neutral
the motor still pulls great. No loss of power.
When sitting in the driver seat and the noise is happening it sounds like it’s coming from the driver fender/t belt area.
Valves were adjusted not too long ago. Like 1.5 weeks ago.

I’m stumped at this point. The only thing I can’t think of the belt needs to be a little more tighter than 3 cam gear teeth .. but wouldn’t it still make the sound in neutral then

 

flapping noise? loose belt or something in the wind....


Why would you not want to check the timing belt again?

 

That’s the thing I did check it. I even re tensioned it twice.
So im kinda at a loss of things to check lol

 

It only happens under load.
Only thing I can think of is tightening the tension a little bit more

 

When was the last time you replaced the tensioner and spring?

 

I haven’t replaced it. Has anywhere from 40 - 65k on it.
What made me mess with the belt was it was whining a bit so I knew it was too tight.

 

It was probably whining from the get go, you're now gettin around to it after 45k miles and by this time the belt has probably stretched

 

From 3k-4.5k? That’s alot of fapping.

 

Check the slack on the timing belt after aligning the cam and crank gears to their specific marks.

 

The belt has no more than 10k miles on it. It’s a new gates belt.
I cannot turn the belt no more than 90 degrees.. like I said the only thing I can think of is to tighten the slack a little bit more. Maybe 3.5 or 4 can gear teeth ..?
Im going to give that a shot today once I get home from running my errands

 

So you didn't really follow what the FSM stated to tension the belt?

 

unless I had used the wrong manual.
Line everything up TDC soon the pulley CCW 3 cam teeth. Tighten tensioner.
Which is what I’ve done.
and from what I’ve read is the timing belt should not be able to turn more than 90 degrees. Which mike doesn’t.

 

something wrong with your google translater?

 

No my hands were dirty.
I just got done re doing the whole timing AGAIN as well as “helping the tensioner spring” and the noise is still there. So I don’t believe it’s the timing belt.

 

I’m beginning to think it’s transmission related since it does not happen in neutral. If I push the clutch in while the noise is happening it’ll go away / I cannot replicate the Noise unless in gear under load. Engine is healthy no power loss. It’s my beater so if it breaks it breaks. I’ll pick up a spare LS tranny or something and get this gsr fixed if possible when it goes.
And it’s more like 2.5k - 3.5k Rpm that it happens.

 

K

 

Thanks for the replies

 

NP