CIS pop off issue

[marksearls]

My car was not run for a couple of weeks. When I tried to started it, I heard an unusual sound from the engine bay and the car would not start. I am no mechanic by any means but I lifted the lid out of curiosity and looked around and everything seemed fine. I then took off the air cleaner and found the pop-of had itself poped off from the pressure, I presume. I then put the pop-off mechanism back in place,(after I removed the ring of old epoxy) put the air cleaned back on and presto, she started right up! It is now re-epoxied and runs great.

Has this happened to anyone else and is my spring too strong? Also, should I check anything else?

[rwest]

Pretty common issue, I had the same thing, don't know if the epoxy just gets old or doesn't get a good bond to the airbox.

Best,
Rutager

[Jdub]

Yup, heard of this before. Be sure you have no air leaks around the base of the pop off valve by laying in a decent amount of beading. Spring strength is not related to this issue - the epoxy gets old and brittle by heat cycling.

[born2cruze]

Sure has, as stated the epoxy gets old and brittle

[marksearls]

Thanks for the replies. I did clean the old epoxy off, who knows how old it was.

[don gilbert]

I gave up on epoxy, it will eventually fail, leaving you possibly stranded. I have used black urathane on around 6 of them now, no failures yet. my own still holding after 5 yrs.

[MongooseGA]

This happened to me about 3 weeks after I bought my car. Scared the crap out of me because I was still in the "if anything goes wrong with the car, my wallet is screwed" phase. Called my mechanic and he told me to check the back-fire (pop-off) valve. Voila! It had come out. Replaced it and the car started right up.

[Howard M]

Happened to me too, years ago. Since then I've carried a rubber expansion plug of the appropriate size in the glove box, just in case. Of course, the valve never came out again (umbrella effect).