I had my car checked today. It is not an exhaust manifold leak. They said it is probably valvetrain. But they cant do anything for two weeks. So what can i do to try and narrow it down?? It is ticking at idle, and throughout the rpm range. I dont know how else to describe it...

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1991 WS6 Trans Am
Medium Green Metallic
Beechwood interior
305 TPI
TH 700-R4, Auto
T-Tops, PW, PL, PM
Keyless entry, alarm
Flowmaster Muffler
Monza Dual Tips
K&N Filter

 

is it dependant on RPM ?

valvetrain is More like a Chatter, and should get Quiter with the hood closed.

If your absolutely sure its not an exhuast leak, than a mal adjusted rocker is about all it could be )



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60 Ranchero - Project ( Money Hole )
85 Sport Coupe LG4 - Daily Driver

Just another Hot Rod kid, or thats what they all tell me.
Livin' the Stereotype

 

It gets faster with higher rpm's..but it is audible at idle, all the up until the loudness of the engine drowns it out..then as soon as you let off, it comes audible again...how can i find out which rocker is out of adjustment???

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1991 WS6 Trans Am
Medium Green Metallic
Beechwood interior
305 TPI
TH 700-R4, Auto
T-Tops, PW, PL, PM
Keyless entry, alarm
Flowmaster Muffler
Monza Dual Tips
K&N Filter

 

Sure its not your injectors ticking? Mine are loud and I can here them while sitting in my car at a stop light.

 

I have the same issue as Mkos. Loud injectors on my 94.

Valve tap you can diagnose by getting a mechanic's stethescope (long probe on the pickup). THen get an old valvecover, cut the top off, install it and install a set of rocker arm oil deflecting clips (available everywhere). Put the probe on each rocker arm stud with the engine running and listen for ticking. When you get to the offending valve it will go from a mild ticking noise to a loud "clacking" noise. You'll be able to tell- don't worry about that.

 

Could it be your lifters, maybe they have collapsed. But then that is more a tapping noise.

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'86 IROC
T-TOPS, TINTED WINDOWS, BRAKE LIGHT BLACKOUTS
GM GOODWRENCH 350
EDELBROCK TES HEADERS
FLOWMASTER
EDELBROCK 600CFM CARB.
KN AIRFILTER
UNDERDRIVE PULLEY
ACCEL HEI DISTRIBUTOR
2:73 GEARS

 

24,

Damon has the right advice.

Here is the poor man's way of listening:

Get a long screwdriver, stick the pointed end on the valve cover right over where the rocker would be located underneath it and..........

Stick the blunt end to your ear and listen.

You'll hear it then.

BOR

 

Damon, just curious how you hold down your modified valve cover on center-bolt heads...

 

Me too.
Yesterday I too had that tapping sound, sounds like the left bank. Increases with rpm 1500 or more. I was thinking loose rocker but now that it's been mentioned, a bad lifter sounds more like it.
Any way to check a bad lifter? Or Just blow it out and replace it?

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"It's not about going fast all the time; It's knowing you can, anytime"

 

The only way I know to check to see if a lifter is bad is take the intake and carb. off and pull out the lifters.

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'86 IROC
T-TOPS, TINTED WINDOWS, BRAKE LIGHT BLACKOUTS
GM GOODWRENCH 350
EDELBROCK TES HEADERS
FLOWMASTER
EDELBROCK 600CFM CARB.
KN AIRFILTER
UNDERDRIVE PULLEY
ACCEL HEI DISTRIBUTOR
2:73 GEARS