Where to hook up smoke machine?

[BlackBart]

YAY! (like this?)

Rajput_(Jodhpur)_(8411728143).jpg (297.15 KiB) Viewed 456 times

[scot850]

Well that is great news. I am having a similar running battle with a a friends car and I have swapped the cap for a brand new one I had and it made no difference. I think we will have to smoke the system like you. I think there is an issue around the fuel tank area.

Neil.

[rick4484]

scot850, my car had multiple leaks, and I created one in the large hard plastic tube that runs from the PCV to the PTC. So, I replaced the PCV system. The 3/8" hard plastic tube of the PVC contained in the foam rubber sheathing that makes the 90 degree bend around the engine, cracked in a few places when I tried to "adjust" it. I could hear it break as I was forcing it in one direction. The smoke machine confirmed the break. Without using a smoke machine I never would have found the leak in the PCV tube. Apparently, you can replace the hard plastic tubes of the PCV with aluminum or copper tubing. Check out RobertDIY's videos on that. Also, the gas cap can be a source of a P0455 issue. I had a Stant brand gas cap, which I purchased from one of the local automotive supplies like AutoZone, which I replaced with a new Volvo cap from IPD ($40.00), and that finally ended my vacuum leak ordeal.

[scot850]

Again good news on your car. The 98 V70 NA of my friends, had a full Volvo specialist PCV rebuild, and I have been through the carbon filter pipes and replaced and checked the valves were operating. Swapped one out with a spare used one and it made no difference.

The car has had this issue for around 8 years since she bought it and there have been several 'pro's in there trying to fix it and failed.

I need to find time to get it smoked in case I missed something or just can't see it at the back somewhere. Just don't like the check light being on all the time.

Neil.

[brunocerous]

Inspiring to hear of a vacuum leak conquered. I bought the same smoke machine to tackle my own. Thanks for all the info!

[Andrew Vanis]

"Where to hook up smoke machine?"

Many responses and not many suggestions where to connect the smoke machine - I was looking for this info as well.

I connected the smoke machine to the lower hose of the EVAP valve located atop the radiator fan, into the hose that comes up along the radiator fan and into the EVAP valve. Took the hose off the lower nipple of the valve and connected to it the smoke machine. I figured the valve should be shut when operation so its an access to the EVAP system..

A (what seemed) a long while later I saw smoke by the fuel filter. The small rubber 90 and another larger diameter connecting hose were split. I figured it took extra long since the tank is almost empty so gas tank had to fill up first.

I would not have found that with my eyes.

Another indicator of a leak was that the smoke machine never built up any pressure when connected to EVAP like it did when I put my finger over the smoke delivery hose.

Will replace those two leaking hoses tomorrow and re-test.

I'm using this machine bought off Amazon a couple years ago for $110
https://www.vxdas.com/products/vxscan-v ... k-detector

[scot850]

AS I am fairly convinced the issue is at the back of the car, I was planning to do the same, and disconnect the long hose that runs to the rear of the car and smoke that to see if I can find the leak which I suspect is above the fuel tanks.

Neil.