Purge Canister Solenoid Valve Hose Trouble

[strikefast]

I've been getting CM code 172 on my early 92 XL Thanks to this board, I realized that it might not necessarily be the O2 sensor that was "causing" the lean running condition. Under my hood I found that the purge canister solenoid valve had a broken white vacuum tee. One side of the tee had broken off inside the vacuum line that runs to the intake manifold. A vacuum leak is definitely a possible cause for the lean condition.

I figured no big deal. I'll just order a new purge valve (which I did from RockAuto) and replace it, extracting the broken piece of plastic from the vacuum line when I get ready to do the repair. In the meantime, I just taped it together as best I could.

The valve arrived, but I'm having a devil of a time getting it installed. The issue is the tubing. Inside the outer rubber vacuum tubing that runs from the purge canister to the valve to the intake manifold is a hard, black plastic inner tube. I assume the purpose is to keep the vacuum line from collapsing. However, I'm not sure how to deal with it. It flexes a little, but not very much--it is more hard than soft.

I disconnected the vacuum line between the canister and the old valve, and pulled the outer rubber hose off. The black plastic that remains seems to have a death grip on the side of the white tee from the purge valve. I'm just not sure how to get it off.

Is it some kind of heat-shrink tubing? It seems harder than other heat-shrink tubing I've seen... Whatever it is, it would seem I need to save it to use with the new valve.

On the side of the purge valve that runs to the intake manifold, I now understand why I also had trouble getting the broken piece of the white tee valve out (I can feel firmness in the line that runs to the intake, so I assume this hard black plastic runs the full length of that hose as well. So that one seems even harder to get out.

Do I have to replace all the hoses, too? Is there a way to intelligently extract my purge valve from one side and the broken piece of white tee from the other side?

 

[Jason94sport]

When I replaced mine that plastic broke in the tube also. I took the hose out & just smashed, pry'd, & ground it down with a screwdriver. It was hard & time consuming but I was able to get most of the white plastic out. At least enough to hold the new valve in place.

 

[BrooklynBay]

Why not just cut the piece of plastic off, and reconnect a piece of rubber hose from the most accessible point?

 

[Jason94sport]

I didn't have any hose & a way to get to a store when I did mine.

 

[StillKicken]

Strikefast,
I had to replace the vavle cover gaskets on my 94 Ford Explorer. Everything went great...until time to reconnect the Purge Vavle cannister. I didn't the the hose was rigid either until SNAP! I went to Advance and they tole me the piece was like $90 so I said I was going to try and fix it myself. If ya look around, there are some rubber extensions, reducers and such. You might have to be a little enginuitive, but might be able to make something work.

 

[strikefast]

Thanks for the suggestions. I ultimately decided that this firmer, inner plastic tubing must have some degree of flexibility. So, I used vise grips on the short piece of tubing between the solenoid valve and the canister to see if I could get adequate grip to remove it from the side of my solenoid valve that was still intact. (The end of this short tube closest to the canister just pulled out fairly easily.) Anyway, I established enough compressive force on this black plastic tube with the vise grips to be able to slowly and gradually rotate the tubing back and forth and eventually pull it off the old solenoid valve inlet. I applied the vise grips a safe distance away from the solenoid valve (i.e., beyond the end of the solenoid valve inlet, which was pretty visible from the protrusion the nipple made in the exterior of the black plastic tube).

I was able to work it off fairly quickly like this once I had the vise grips set properly. For me, this setting was enough force to deform the side of the black plastic tubing, but nowhere near enough to completely pinch the tubing shut. I figured that would risk breaking/cracking the plastic tubing, which I wanted to avoid. Once I released the vise grips, the tubing returned to its normal shape. Success!

On the broken side of my solenoid valve (i.e., the side that ran to the intake manifold, where the valve outlet broke off inside the tubing), I decided to remove the entire vacuum line from where it connects at the intake manifold--it pulled off easily. I then decided to take a play from Jason94sport and combine it with my vise grip approach. I inserted needle nose pliers into the end of the inner plastic tube to grip it, then pulled back the outer rubber hose to expose the part of the firm plastic tubing containing the broken white outlet. Now that I knew this black plastic stuff had some flexibility and resiliency, I used the same setting on my vise grips to apply force to the outside of the black plastic tubing. Before starting, I held the vacuum line such that the end with the broken outlet valve was at the lowest point. This was to keep the broken white pieces from falling deeper into the line as it was crushed. This was much easier with the entire vacuum line disconnected and removed from the Explorer.

This time, however, I applied the force directly over the part of the tubing that had a death grip on the broken white outlet to crush it. After doing this two or three times around the circumference of the plastic tubing, the white outlet was crushed. I used the needle nose pliers to pull out the pieces. It came out mainly in three or four long white shards. After making sure the line was clear of debris, I hooked up the new solenoid valve into the two ends of the black plastic tubing (with a very snug fit like the original--good!) and reinstalled everything.

Thanks again to everyone for your suggestions--I really appreciate it!

Time will tell if this is enough to keep CM 172 away

 

[BrooklynBay]

How much was the new solenoid?

 

[strikefast]

I got the Motorcraft part from Rock Auto for ~$40 plus shipping. MSRP was $60-70, I think. I later saw a Wells part on Autozone's website for ~$34. Given the price I paid for the Motorcraft part (same number as the one stamped on the old part), I was pleased with it.

 

[Jason94sport]

I got the wells one.
Glad you got it working