I drive a 94 del sol vtec. I have a B16a3 in it as you probably know. My engine made a really loud snapping sound as soon as I hit the vtec in second gear. It wasn't like the normal bark the intake makes but something harsher and louder than the normal intake sound (i have a short ram intake by the way). It went in sequence with the bark of the intake though. The engine seemed fine otherwise no extra noises or smells and had the same amount of power. It only made the sound when i was in the vtec range. I could give it gas below the vtec and it would sound fine. I was just wondering if anybody had any idea what was going on. My car has 200 000km on it, something like 120 000 miles and it was below
0°c but the car was completly warmed up. Thanks for any help.


Modified by superfrk at 9:29 PM 1/11/2007

 

I thought about it today and i'm thinking it could very possibly be a valve contacting my piston. It only happens when the vtec is engaged. The vtec lobe had higher lift and, correct me if i'm wrong, more advanced timing. This could explain why the valve would touch when the vtec is engaged but not when it's not engaged. If this is the case, could i have gotten away with it, or do I have big problems in store for me.

 

Is this motor stock? It might just be how it sounds in vtec thru the short ram. Does it sound like that in any other gear? There should be no piston to valve contact with stock everything.

 

As far as I know the motor is stock. I only bought the car a couple months ago, so i don't know if the timing belt has ever been changed before. I've got one coming in the mail that i'm going to put on as soon as i can now, just to be sure. I don't think it's just a vtec sound, because i've ripped it through the gears many a time and i've never heard it make a sound like this. I did notice however that it only seemed to do it in second gear, not so much in third. I don't really know what it did in other gears, because as soon as it started i let out of it completly. I tried it twice to make sure something was happening but I haven't engaged my vtec since. I don't want to lose my engine. Is it possible my belt could have jumped a tooth on my gears? I'm going to check the timing as soon as i can no matter what.

 

It was also below freezing last night and it was probably one of the first times i've driven it in weather that cold. I don't know if the denser air was just giving me a more powerful sound or not. It was a lot louder than the normal sound my engine makes when in the vtec

 

You would know if it jumped timing..It wouldnt be running good at all.

 

Now i hope i don't sound like a complete dumbass, but i could swear make engine makes a different Vtec sound when i let the car warm up idling, rather than warming it up driving. I had a friend with a Toyota Cressida who said that his distributer automatically adjusted itself to the way the car is running. That could could just be BS, but if not, could it be the same thing? I know it's just egnition timing and has nothing to do with my valves, but if it's advanced could it be giving me a louder intake sound?

 

I'm just throwing stuff out there, because it was like nothing i had heard before.

 

Well when you cross into vtec, the computer switches to different fuel and ignition maps, but the distributor doesnt "adjust" itself.I say its just the sound of vtec.It could have changed pitches from the temperature.