what is this noise??? plz help

put a couple new clamps (but still need 1 egr), but i when i started her up i got this weird humming noise coming from the front of the engine?? timing belt?? water pump?? i cant tell ive never ever heard this noise come from my truck until today.. its also bogging out and back firing really bad now too.. never has before unless i forgot to hook up a vac hose after messing with the carb...


anyone???? would not having that hose clamp on the last egr do that??? i doubt it..





p.s. sorry i have an exhaust leak at the cat cuz no one has the gasket i need and its kinda loud lol

Those hoses are not EGR, they're air injection.

As for the sound, I hear your exhaust leak, some ticking from the rockers, and a whine that may be from the alternator.

the whine is coming from the front of the engine, center, not near the alternator, the ticking is just exhaust noise its not that loud from the valve cover so i just ignored it cuz i have adjusted the valves 3 times lol and i always that that egr was exhaust gas regulation and that the exhaust gas is going into the carb.. but i also dont really know that much about engine management systems lol

Yeah, EGR is for Exhaust Gas Recirculation, but the EGR Valve is on the intake manifold.
Mazda didn't use an Air Injection Pump, their Air Injection System was supposed to be "Kick Ass" in its time.

Tough to say what the whine is... trying to diagnose in a forum can be tricky.
I wouldn't think its gonna be timing belt related, but it's entirely possible that your timing belt tensioner pulley is beginning to fail.

lol i hear ya on that, the timing belt and tensioner were both replaced along with the water pump last year with the head gasket. so i doubt its that, but it could be im just gunna replace all that agine since the head gasket is leaking. maybe its the drive belt thats whining or something stupid..

Noises are really hard to find sometimes.

I would pull the drive belts and check all the pulleys for rough operation.

Maybe a bearing has started to fail.

There are two of them inside the alternator.

There is one on the power steering idler.

I think there is one on the support that the fan pulley rotates on. Maybe two, stacked.

The AC compressor clutch carries a bearing, and the front of the PS does too.

I hope when yo find the problem you post your solution.

well fortunately for me, i have no a/c or power steering so it would come down to the fan, or the alternator. or the crank pully or like you said a bearing which would suck.. but after it warmed up it stopped, wasn't boggin down or back firing so i think its due to not enough vacuum pressure but ill check it out more tomorrow, im hoping its the fan clutch

id follow your vac lines and make sure there all connected I think there's 2 hooked to the intake box. they like to pull loose. I'd also run some sea foam through the carb. or sucking the carb rev it up at a high rpm then close the choke butterfly repeat this in short burst don't blow up the mazda lol. this creates a high vacuum and cleans out the carb really good.