I have a '95 4runner that has clearly malfunctioned. I hear a loud banging sound eminating from the engine compartment, near the firewall on the driver's side.....any thoughts?

 

Threw a rod, perhaps.

 

shut it off, check your oil, dont drive it till you figure it out. Spun a bearing, threw a rod, possibly dropped a valve seat

 

Unless you pull the motor apart, at this point, it's going to be impossible to determine what's wrong unless you can run the motor to do so. You need to be able to pinpoint where the noise is coming from. Go to autozone or someplace similar and get an inexpensive stethoscope and use that to diagnose the noise location. A screwdriver could be used, but the stethoscope is much nicer....you'll see. (My wife just bought me one....tehe) A loud banging is a mechanical failure and possibly what the other members have suggested. There's a possibility something has just come loose externally and it sounds SO major. It happens. So, you'll just have to look at it. Can't tell you anymore without feedback, though.

 

I think this calls for an EMERGENCY 3.4 SWAP!!!

 

You might be right....

 

That sound you hear is your 3.slow telling you it's time to swap in a 3.4


{probably a rod knock = rebuild = $2k+ (for DIY) $5k+ (for a repair shop) }

 

Yeah, but he was being sarcastic. He doesn't mean it. He's one of the "3.0 Is Good Enough For Me Club" members.

 

just show it who it's master is and bang on it back with a hammer... do it long enough and hard enough, and I guarantee the banging will go away

 

I'm actually more of a "3.4 ain't that much better, and not better enough to warrant the headache or costs of a swap" club members.

 

Chances are somthing really bad has happend, as mentioned it could be many things. I doubt you will really know anything unless you start taking it apart, unless you threw a rod out of the block

 

I'm aware of Coed's feelings on the idea.....

And, I said what I said because.....actually....banging is not a good sound. Atleast, not from a motor.

 

dont know if this is your problem or not..but a few years ago i had a driveshaft incident on the highway @90mph...long story short... this incident bent the output shaft on my t-case, not realizing this..and trying to work the bugs out(while driving daily...never a good idea) the torque converter actually slammed through the bell housing...never seen anything like it before, but it sounded exactly as you described it... use a screw driver to "listen" to the bell housing...if you think this could be your problem...doubt it though...as i said ive never seen that before, or since.