VW Beetle noise from my 1979 308 / Emissions

Hello All,

1) I am trying to locate the cause of annoying sputter my 308 has at lower RPMs ... or that I can only hear at lower RPM's. It sounds like an old VW beetle.

I do not see any sign of an exhaust leak and it does not sound quite like an exhaust leak.

The air pump has been removed, but as far as I can tell all of the rest of the emissions system is there: cat, air pump lines, vapor canister (line coming of bottom not connected to anything) and a few other items that tie into the cannister.

2) Does anyone have the air pump nozzle replacment bungs? I would like to get that mess out of there regardless.

3) There is a piece of flexible tubing that ties into the air duct on RH fender. What is that supposed to be directed to? Mine just termiates under the vapor cannister.

Thank you

 

It's their normal sound. Apparently it's the little silencer holes in the tips that make that sound. Insert a pipe or a piece of sheemetal formed to fit in and see if it works.

 

Where exactly do I fit the pipe / sheetmetal?

Do I insert into the exhasut opening?

 

Yes, slide it inside the pipe to cover all the little holes. I do not promess anything, but I remember a thread talking about this and thats what they said it was.

 

Search "Exhaust Whistle" there are a couple of good DYI threads out there...

 

Talk to smg2. He has the aluminum plugs to replace the nozzles in the head. As for the hoes in the header, you can either use a screw to replace where the pipe connects or have them welded closed.

 

They are trying to tell you, that to replace the Air Injection nozzles in the heads, it's a plug fitting with a length of solid projection on the end, to 'fill' the void the nozzle leaves behind.
There is a nice sketch of it on here 'somewhere"...

Now moving to the "Sampler Bungs" in the header, they SHOULD have plugs in from the factory, on the rear ones, the front side goes with fixed tubes to a location by the distributor. If the rear ones fall out, the proper size BOLT (not screw!) will plug these, or, some weld them closed, if the headers are out of the car.

All of this stuff, (as well as the pumps and rails of the Injection system) can rust out and cause "exhaust leak" type noises..

The insert into the exhaust tip, of the sheet metal, that's the least of your issues, but it does solve the whistling/rattling at the exhaust tip, should it occur.

HTH

Smg2 does make the plugs but only on the occasional run, you can see if he has a set on hand.
You could just pull and cut the nozzle off the old fitting, I have seen the tubing rail side sealed with proper sized ball bearings! LOL!

 

The flex in Item 3) is supposed to cool the RH axle CV seals, to keep the heat of the '78 -'79 cats from melting them.

It does end under your intake snout, but should be pointing down in the direction on the inner CV joint?

That's also correct piping on your Charcoal Canister, the fumes dump in to top line the bottom vents to atmosphere, no line...

 

are you sure that all 8 cylinders are firing ?

 

that was my first thought.... when running on just one bank the engine very much sounds like a VW bug. I had the problem twice. One time it was moisture in the spark plug terminals, the other was bad ignition points... dependent on rpm it was firing on all 8 or just 4 cylinders...

 

Thanks Fellas

1) Are you saying I only need 4 bungs to replace the air injection and that the forward bank just has the gas sample pipes? Are you also saying the sample pipes do not have the intrusive nozzle / collector sticking into the port?

2) Whistle / Sputter - My car is running on all eight. Starts well, idles well, pulls rapidly to the red line and very smoothe. I do hear a slight whistle when I let off the gas and let the engine slow the car. I love that sound The sputter is annoying.

 

No, every cylinder on your model has an air injection port in the cylinder head into which an (obstructive) air injection nozzle is mounted -- so you'd need 8 "plugs" to remove them. Do a search (both here and at the old site) on "108205" for many prior threads.

Typically, each exhaust tube has an exhaust sampling port -- some have a tube assembly to move the sampling location to be more convenient for the Mechanic; some are just blocked with F plug 110860. There is no projection/obstruction into the exhaust tube in either case, but the sampling tubes get brittle and break from the heat/vibration. Try a search on "110860" for prior threads. IMO, it's best to use 110860 to close all 8 exhaust sampling ports and then keep the tubes in your toolkit in case they are ever needed by the Mechanic.

 

Hi, i had the same WV sound on my mondial 3.2...two times...Exhaust manifold was cracked...on the both cylinders heads. once in 2011 and the other in 2012...

 

The rear four tubes ARE in the jack bag, on early models.

Your science is tight!!

The air injectors are one system (into the heads), the sampling tubes are off the exhaust header. (To the OP, not Steve...LOL!)

 

Are you are talking about the air-cooled Beetle sound as it goes down the road, what we used to describe as "a whistle dragging two chains"?