ok, so i got a few questions, and concerns....

1st is that my motor which is the stock motor in my 81zx. (n/a) has fairly loud ticking under the valve cover. lately its been putting a light film of carbon deposits on the outside of the valve cover, on the injector side.
-what is this and why is it happening?...what can i do to fix?-

my second concern is that i was wondering about my gas cap.
is it suppose to be a breatheable cap?. or is it suppose to trap air pressure and not let it escape? cuz everytime i unscrew it, a fair decent amount or pressure rushes out. im sure of the cap being original and not being a random cap that was just throw into it.
-just wondering if its suppose to be like that.-

3rdly is my exhaust. my car is currently muffler free. still has cat on. does no muffler hurt the motor in time or is it safe to run w/o it?

thanks for any help you may have to give....greatly appreciated.

 

#1 sounds like your intake / exhaust manifold gasket is burnt & leaking due to loose manifold studs & nuts (or one completely missing).

#2 yes, gas caps are supposed to hold some pressure, so gasoline fumes don't just roam out of your tank and into the atmosphere which would contribute more to global warming (so they say).

#3 not having a muffler doesn't hurt anything other than someone's delicate ears.

 

Somewhat related question here....the "Ticking" sound from the valve cover.

My L28 makes a ticking noise too - but the valves seem fine - just did an adjustment and timing recently and nothing changed audibly. I've done the "Screwdriver stethescope" test and can't really tell if it's coming from an injector or the valvetrain.

Is this normal for EFI engines (Injectors)?

MY 87 Toyota truck makes the same noises and I've done valve adjustments with no change on that car as well....

Just curious if it's normal or bad (and if so what to do??).

thanks

 

It depends on how "loud" the ticking is.

Obviously there will be some ticking noise from the injectors, but very little to no clacking should be heard under the valve cover.

 

I got one of those automotive... Ok I had a brainfart on what its called but its kinda like what doctors use to listen to your heart and stuff. but this one as a rod on the end instead of a disk. Anyways I found out that the ticking from my engine was from the injectors not the valves

 

stethoscope.




L6's are naturally a little "ticky" the solid lifter heads (even when adjusted) have a quiet tick and so do the injectors.

 

Thats It! Thank you lol On the note of engine sounds, the power steering pump sounds awesome though a stethoscope!