Bolt found on ground, oil leak and engine noise!

Hi,

I got a 1997 toyota tacoma with a problem. About a week ago i got in to drive it and its louder than it use to be. Almost sounds like the exhaust is leaking, not bolted on right. Almost like i put on an after market pipe or something. It went from purring kitten to sounding like one of those low riding mini trucks over night. I got out and looked under the truck, and there is no missing bolts and the exhaust looks fine where it bolts together. No holes in the exhaust. The truck drives great like always. I noticed later its not coming from the exhaust, but up front from the engine itself.

Today i found a bolt laying on the ground when i pulled into my driveway. It is a big bolt, and sure as shit looks the same as many of the bolts under the truck. This bolt wasnt there a week ago, seems to be a link between the bolt appearing and this sound starting.

I climbed under the truck with a flashlight and really looked it over well, i dont see any missing bolts. I do see an oil leak though, its hard for me to see where its coming from it looks all over under there, enough to drip a quarter size drop on the ground, good size leak since its just sprayed all over under there. Checked my oil and its lost about 1/2 quart in the past month. This truck is fairly new to me though so this might have been there already. This is the first time i really crawled under there.

My question is,

What would make the engine sound like it all of a sudden developed its own after market exhaust? Would the found bolt be connected to the sound? Its really loud when i first take off, you can barely hear it when im on the freeway. Any ideas? I already checked where the exhaust bolts onto the headers, it looks okay.

 

What the hell does that mean?

 

LOL!!

 

Are u serious?

 

Take a power washer, some degreaser and clean the crap out of that thing, top and bottom. Then, add that 1/2 quart. Drive it around for a bit, and check under the truck again. Hopefully, you should see fresh splatter from your leak. You might want to get one of those little mirrors on a telescoping rod (you can get them at auto parts stores) so you can see in more tight spaces.

I think you can also rent a sound scope thing. I don't know what they're called, but they look like those things doctors wear to listen to your heart, but with a stick on the end (give me a break, I'm brain farting right now). You can use that to help isolate noises by putting the end of that stick on different parts to listen for noises.

Good luck. And yeah, low riders are lame...

 

What size is the bolt?

Check your header to downpipe connection.
It's not visible unless you know what your looking for.

 

post a pic of this so called bolt. maybe someone stole your catalytic converter.

 

^^^ x2 That's what I was thinking. Seems like it would be obvious though.

 

i looked at the cat converter this morning, i believe its still there? Its that thing with the holes in it, i believe its attached to the muffler pipe before it goes into the engine. I googled a pic of the cat converter off a toyota. Good idea though. I checked all the plugs they arent backed out, in the process i broke off one of the connectors in the boot, so i had to go buy another spark plug wire and tools to get out the old spark plug ect. What a pain in the ass that was!! ha. oh well. Heres a pic of the bolt and my truck.

 

Exhaust mani?

 

check your exhaust manifold mid section. passenger side. you should be able to see it passenger side engine bay directly below heatshield of exhaust manifold. 3 bolts I believe. 12mm

 

the bolts are all there. i followed the exhaust from the back to the front on both sides of the engine, all bolts accounted for. I must have spent 2 hrs last night under the truck looking for a missing bolt...didnt see anything. The noise seems to be coming from the engine somewhere. If its idling and you step on the gas you cant hear it, if you put it in gear and give it the gas thats when it you can hear it most. Sounds like escaping air, im sure that stupid bolt is the cause and im sure its somewhere only visable if its on a lift with my luck.

 

run seafoam in your truck and see if you can detect any exhaust leakage. It'll smoke up quite a bit.

 

I just read on another forum someone had this problem and it wound up being the oil they were using.

When i bought this truck a few months ago, the guy said he used only fully synthetic. He was an asshole and not trust worthy so i didnt believe him. so when i checked the oil level it was a quart low so i just bought some cheap oil non synthetic and put it in. That was about a week before the sound started. It was the right weight for this truck though. Could that possibly have something to do with it?

 

No, but if you have watched Tommy Boy you will find that leaving an oil can under the hood doesn't let the hood latch correctly... doublecheck your own work, make sure its not the drain plug or something absolutely ridiculous like that.

PS, never mix synthetic and non, drop whats left of the oil and replace it, along with the filter... if you mixed synth and non then you could be in for something way worse than a loud exhaust.

 

Found where the bolt went!

Catalytic converter, right where it meets the exhaust pipe. I dont know how i missed that before. Going to run the truck and see if that is the cause of the noise.

 

Yeah, that would do it. Exhaust leak will kill the power of your engine.

 

Yep, no more noise!!!!

Thanks alot guys for your help.