Ok so i have searched and this is what i have found. It a really old thread and nobody has responded. I have the exact same problem with my car. It a very loud ticking sound that can be heard at idle and at light throttle up to about 4-5k rpms. The ticking rate does not increas with the rpms. Their diagnosis was the air pump but i do not have one, so im very confused because my problem sounds identical. My turbos i believe are shot because there is lots of blue smoke coming out. I swapped over another set of turbos that i had a couple a weeks ago and the ticking got worse and the smoke got worse. Could it be that the shaft seal were just in worse shape with the turbos i put in and the noise i hear is the shaft actually rattleing around inside the turbo? or an exhaust leak of some kind? Please help! I have another set of turbos that are in mint condition that im putting on tonight. Hopefully that will solve the smoke issue and im also going to check the actual exhaust manifold while im in there for any cracks.

Some othe info that may help: No air pump, no a/c, no p/s, and non sequential set up. and a link to the other thread https://www.rx7club.com/3rd-generation-specific-1993-2002-16/ticking-sound-under-throttle-air-pump-482008/

 

Could be either an exhaust leak or one of the turbo flappers (wastegate flapper, turbo control door, etc.) isn't tensioned at idle and is flapping around. If you didn't fully remove the turbo control door from the manifold and just have it stuck open, it will tick and make noise, as will wastegates that don't have the actuator tensioned properly so they're loose.

Dale

 

It's just valve chatter.

 

Well we will see by tomorrow, when i removed my turbos tonight there were only 2 of the 7 bolts holding the turbo's on and they were both loose. So hopefully that will solve my problem when i put the new ones on tomorrow with all 7 bolts.

 

Well i put my new turbos on and the ticking still pursists. I know its not an exhaust leak because i was sure to seal everything and everything is tightened down. My next guess would be the wastegate chatter. Someone said it couldnt be the wastegate because it does it at idle. Any ways to fix the wastegate chatter?.......tick.....tick.....tick.....its about to drive me nuts!!

 

Probably a stuck lifter.


You might try this:
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/fixed-my-rattle-noise-here-what-169138/

 

Does the ticking frequency change with engine RPM?

You might have a loose area at the exhaust gaskets, if you re-used your stock studs/nuts. Once the stud and nut seize, they are set at that length permanently. Unless you put it back in the exact same hole in the manifold, it can bottom out when torqued such that it's not squeezing anything, then you get a leak. You'll know by the soot path on the gasket.

Before going out and spending $200 on new mazda hardware, it's worth getting some M10 washers and putting one washer under each stud/nut to see if that is enough to prevent them from bottoming out.

Dave