z28guy1999

i bought the car two weeks ago and have noticed that it has a ticking noise. I read somewhere that there is a know issue with Mac headers and noises. I just wanted to double check this and get any other opinions on the noise.

conan

iTrader: (5)

Check for a exhaust leak at the manifold gaskets. How loud is the ticking? Could be valve train noise.

z28guy1999

the valvetrain is making the sewing machine noise, i think the ticking is from the exhaust, next time i have a chance ill put it on my lift at work and check the headers

Phoenix 2001

I have a minor ticking nosie on mine as well, I think its the header it self.

3.8SFITURBO

iTrader: (10)

My MACs tick also. It sucks.

SiL3NtXWS6

iTrader: (17)

Are you sure it's not the AIR check valves?

OldeSkool

good thinking! get rid of the AIR... if it doesnt solve your ticking, at least you'll lose some weight.

z28guy1999

glad to know im not the only one having this issue

3.8SFITURBO

iTrader: (10)

Explain please

98Z28MASS

iTrader: (6)

yea i have the same problem with my macs. The air check valves are those little metal arms that attach to your headers. They have a round bulb shaped end that runs to your air hoses. When you install your mac headers if you dont use restrictor plates between where the air system connects to the headers (search restrictor on here and you will find it) you will burn out your air check valves within a few weeks. I didnt know this and sure enough mine burnt out and even when i replaced them and used restrictor plates it was still there, not as loud but still there so my suggestions is to just deal with the noise and the SES light that will soon accompany it if it isnt already there and then remove all the air stuff when you get your car tuned. Hope that helps!

3.8SFITURBO

iTrader: (10)

Yeah that helps alot LOL thanks! I did not know that. I did not use restricter plates so I am assuming that they are blown. Do you know if new ones and plates are very $$$$?

98Z28MASS

iTrader: (6)

A pair of new air check valves run about $40 and you can make restrictor plates yourself with a piece of sheet metal and some tin snips. The pattern is just that of the air gaskets that are between your air check valves and your headers. Here is the link to the restrictor plate mod. http://riptide63.homestead.com/restrictor.html

Just follow the steps and it should solve the problem. Again mine still ticks somewhat but not nearly as loud as it did before. Another cheaper solution is to just tear out the air system and just buy block off plates for the air fitting on your headers. You will have an SES light but can just ignore it if it doesnt bother you. Any other questions you have feel free to post them or PM me. Good luck!

jlashley2001ss

iTrader: (5)

what about the AIR check valves w/ long tubes? can u blow them out too??? mine has a slight tick but seems to be coming from say the merge collector.

98Z28MASS

iTrader: (6)

Im sure you can blow out the air check valves with longtubes as well, the problem is just known more for happening with mac midlengths. It has to deal with the air pulse thats coming from the headers. Since the headers are flowing a more significant amount of air than the stock manifolds the air system tries to compensate and flow more air to the cats. The air system is in place the heat up the cats so that they can perform their job more efficiently and with the headers flowing more air to the cats than the stock manifolds the air check valves try to work harder to compensate and end up burning out. However, if the sound is definately coming from your collector then it could be a small leak in the collector that is causing the tick. My suggestion is to try to listen very closely and pinpoint where the sound is coming from but with any modification of any vehicle you are goin to hear different sounds that you did not hear before, such as increased valvetrain noise. If its not setting off an SES light then I wouldnt worry about it but thats just my opinion.

jlashley2001ss

iTrader: (5)

about a month before i got my long tubes installed the SES light came on and the code was the drivers side AIR CHECK VALVE. i reset the PCM and after a few miles it came up again...same code. so i do the PCM reset again and finally stayed off. im thinking that since i already needed a AIR CHECK VALVE thats what may be causing a ticking noise. my exhaust guy checked over everything and said there werent any leaks at all so go figure!!

jlashley2001ss

iTrader: (5)

TTT guys want some info on this

98Z28MASS

iTrader: (6)

Hmmmm, did you replace the drivers side check valve or did you just keep resetting the PCM till it stayed off? If it is still ticking and the code it set off before was the drivers side air check valve and you want to keep your AIR system then id say replace the drivers side air check valve and install the restrictor plates and you shouldnt have the ticking anymore or it should be reduced, especially if your exhaust guy couldnt find any leaks.

jlashley2001ss

iTrader: (5)

yeah he said there wasnt any leaks. he said he checked everywhere. yeah i keep resetting the PCM til it stayed off. wish there was somebody that would do the restrictor plates for me. anyone in the NC area that would do it feel free to pm me.

98Z28MASS

iTrader: (6)

Restrictor plates are actually very simple to make, you can even buy a set of air block off plates (most sponsors have them), then drill the same sized hole as listed on the link i posted above for the restictor mod, then just bolt them in.

CRL 01 SS

iTrader: (4)

Or you could just get the codes deleted, get some block-off plates and get rid of all of the AIR junk. Makes the engine compartment look a lot better, and it's easier to change plugs as well.