Passenger side ticking/rattle noise

'99 Blazer 4wd 4.3L auto trans, 157k.

I recently replaced (4 mo) head and lower intake gaskets and R side head due to coolant leak into #6 cyl causing cracked head. I recently noticed a "ticking" sound coming from that side during acceleration but not audible at idle. I am thinking a bad valve or lifter, but would appreciate any wisdom. Oil level is normal, recently changed it with Valvoline High mileage, have not checked the plug magnet yet but will do so this weekend when I have time.

Please give me some good news, this thing is killin' me right now!

'99 Blazer 4wd 4.3L auto trans, 157k.

I recently replaced (4 mo) head and lower intake gaskets and R side head due to coolant leak into #6 cyl causing cracked head. I recently noticed a "ticking" sound coming from that side during acceleration but not audible at idle. I am thinking a bad valve or lifter, but would appreciate any wisdom. Oil level is normal, recently changed it with Valvoline High mileage, have not checked the plug magnet yet but will do so this weekend when I have time.

Please give me some good news, this thing is killin' me right now!

Could it be a exhaust leak?

I was thinking that could be an option because of the sound, but what is an easy way to diagnose? I replaced the exhaust gaskets during the previously mentioned repairwork and resurfaced the mating surface on the manifold. Thanks for your help...

I was thinking that could be an option because of the sound, but what is an easy way to diagnose? I replaced the exhaust gaskets during the previously mentioned repairwork and resurfaced the mating surface on the manifold. Thanks for your help...

Good ear helps.

Exhaust leak makes more noise cold and some times black around leak.

Sounds like what I call NORMAL for the 4.3L Blazer. Mine does it also along with the piston slaps. It has been doing it for over 30,000 miles. So I wouldn't worry about it until it blows up. That is what I'm doing.

Sounds like the noise is coming from y pipe/manifold area. I took both y pipe apart to be able to move exhaust and still could not get at the donut gasket to replace it. I could inspect it and it looks worn but not bad. Am I missing something here to make this easier to remove? I just couldn't get enough clearance to remove it. I hope I dont need to remove the manifold to do this seamingly easy repair. All manifold bolts were tight and gaskets looked ok from what I could see. Thanks for your help.

Mine was doing the same thing. Catalytic convertor had come apart inside.

Mine was doing the same thing. Catalytic convertor had come apart inside.

I just replaced my converter because of this, but the noise was a definite rattle, there was no way it would sound like a tick.

Lay under your truck and bang on your converter. If you hear the noise then you need a new converter.

Just a thought on not wanting to remove the manifolds - pull the bolts for the motor mounts and lift the engine a little bit...

Replaced right donut gasket today and it was not cause of noise. Continued to look further and noticed black residue around #2 ex manifold on head. It seems the gasket slipped and rotated forward causing the backside to leak. Bolts were tight and it looked like the gasket had migrated somehow to cause leak. Maybe when I put them in during previous work? Anyways, problem fixed for now. I read on Autozone repair guide 2 middle bolts torque to 11 ft and others to 22 ft. Is that correct? Thanks for the assistance fellas! Now onto the radiator leak, again!