Car Popping (etc) on Deceleration
 

My 914 - 1.8 pops and and burbles a lot during deceleration.. to the point of being embarrassing. What is causing this? Is this a muffler / exhaust system issue?

Thanks for any help!!

David

My 1.8L did this right after I installed a new Bursch muffler. It seems to have calmed down now but for a month or two it was embarrassing.

Not sure what the actual scientific reason is.

If it back fires, it is an exhaust leak.

If you are running carbs it could also be a clogged idle jet...

-Tony

The popping is usually unburned excess fuel meeting up with some fresh air (oxygen). First I'd look for an exhaust leak. Fresh air actually gets sucked into the leak and combines with the gas to pop. Next I'd check the deceleration valve to be sure it's working OK (there's a description of how to check it in the Haynes or Bosch manuals). Next I'd make sure that there are no sources of raw gas (leaking injector or cold start valve).

I would agree with he possibility of the exhaust leak at the head. A different and easier check could be the throttle switch. Just disconnect the connector run the car and if it's the switch the problem will be gone. I had the problem myself and its that easy. Of course i've had many exhaust leaks too do the same thing. Hope that helps!

every time i've EVER had a popping/burbling on deceleration issue... it was an exhaust leak. check all of your exhaust gaskets.

good luck!

obin

Thanks everyone! I'll look at all the options! It seems that the exhaust system is fairly tight (if holding your hand over the tailpipe counts! http://www.pelicanparts.com/support/smileys/smi14.gif ) News at 11!

David http://www.pelicanparts.com/support/smileys/yltype.gif