Vapor Canister / Charcoal Canister Specifics Needed (What did the mice eat?)

New to this forum. My '88 BII lives in a '66 body, but is pretty much otherwise stock '88 at 60K miles. Mice have chewed around one of the big holes on my vapor canister. It looks incidental, but I'm suddenly having symptoms like there could be an evap system issue. It was starting great every day and night in temps in the low teens and ran great bouncing through rutted snow and ice for a week and then, on the morning of the big thaw, it didn't want to start, acted like it was out of gas, finally started but hesitates, misses, dies, etc. I know these symptoms could be caused by lots of other things, but I do want to better understand my specific canister set up since I see it has some damage.

Here's what I see on my 1988 2.9L EFI BII: My canister has what seem to be the inlet and outlet lines running to nipples on the top of a smaller segment on the driver's side (a side section that some other models' canisters don't have). The 2 lines and connections here are all intact.

Then, the main two segments of the canister each have big holes on top (like other similar models do).

The driver's side big hole has a cap that is ridged inside so it isn't air-tight and the cap seems designed to "breathe". (On the 2.0 and 2.3 diagrams I found, this hole is where the inlet and outlet tubes both attach with one connector - not on my 2.9, though).

The passenger side big hole does not have a cap. This is where my friends have chewed a bit - shortening the nipple though not dramatically increasing the size of the hole. You can see down in there to the plastic grid (that holds the charcoal, I guess).

I looked (in the rain at night) for fallen lines that might have been detached from here, but don't see any. I put my finger in the hole while it was running and didn't feel any vacuum. I couldn't tell if blocking this hole affected the performance, as my symptoms (hesitation, "missing", dying instead of idling after reving, dying after idling OK for a while) are sparodic and it was idling OK at the moment.

I'm guessing I'm missing a cap...? Or does something else attach here on the big hole of the passenger side? Does missing a cap make a difference, since they seem not to be air-tight? (It is very, very wet here and it could have got some water in there, if that makes a difference.)

I can't find "vapor canister caps" at online parts stores. If they are available, what's the part name? Could I just fashion a cap to keep splashes out (like by taping duct tape over the top and letting the mouse-chewed side of the nipple be the "breathing" part), or is it important that the caps fit "just so" with a fairly exact level of airflow restriction?

Also, I saw two different "vapor canister purge valves" listed (incorrectly?) for my engine at some sites. In the diagrams for carburated engines, it looks like this might sit near the carburetor and attach to the fuel vapor return tube - (but it isn't labeled and it's hard to tell). I don't have an evap diagram for my truck, though. I don't see a purge valve in the vicinity of the canister on mine. Couldn't easily follow the fuel vapor return line last night, but didn't see anything like this part. Should my rig have one of these? If so: where does it go; how many nipples should it have; and what lines connect where?

Thanks a million!

Page 104,Lmc truck Bronco 2 catalog.You can buy the cannister and change it pretty quick.

Thanks for the quick response. I do have that catalog and use LMC a lot for vintage bronco parts for my truck's body, although I found this canister cheaper at other sites online.

Tell me if I'm wrong, but I don't think I need a new canister, though. At sites that show the canister for the 2.9L, it doesn't come with the caps. (LMC's illustration is not of my canister). Even the cheaper sites have these around $60 - which seems a lot to pay to get a little plastic cap, even if it was included.

If the little section of the riser tube the mice ate is important and the exact cap fit is important, I'll hot-glue gun or duct tape that little chewed spot and find a cap (junk yard? or are they online somewhere?). As it is now, the one cap from the other side will sit on there without falling off if I move it over - the tube isn't that damaged. It would leave just a little extra opening (.5" x .75") on the side of the tube where a little more air could flow.

It sure seems like these caps are supposed to allow air flow anyway and a piece of duct tape over the top of my un-capped hole (with the little mouse bite on the side as the "breathing" hole) would serve the same purpose as the vented cap....right?

I just want to be sure I'm not missing some other part (other lines to the canister, or?) and that the canister system doesn't require super exact air-flow resistance.

Thanks again.

if it makes you feel better

I have an 87 ranger and my evap cannister is clogged with mud. litterally up to the cap. it runs, it drives and i dont have the symptoms you describe. good ol hot glue and bubble gum should be in order for you

Update to say Rangermilitia was right. Mouse-chewed canister wasn't causing any symptoms. Got a new computer chip 10 months ago and all was cured. Never hot glued it and never learned if I'm missing a cap or not. Still curious to know more about the canister, but want to let others know it wasn't really a problem for me. The darned mice have chewed up my driveshaft, though.....

There is supposed to be a vent cap on each of those tubes but they frequently fall off.

AD