Fuel Vapor Return Tube

[nobbyv]

The fuel vapor return tube going from the charcoal canister to behind the engine (apparently) was broken when I bought my '97 2.3L. I have searched and searched, and can't tell where it actually goes behind the engine (it was broken way down by the canister).

Does anyone have a pic or can anyone tell me what I might need to remove to access it (PLEASE don't say intake manifold!)

Thanks!

 

[RonD]

You are looking for info on the EVAP system

Charcoal canister has two hoses, one goes to the gas tank the other to the intake manifold, sorry but that is where one hose goes to, ultimately

The gas tank hose is a direct run, nothing in between

But the other hose does have some connections on the way to the Intake Manifold(said it again)

The computer opens and closes a vacuum solenoid on this hose, it will have 2 vacuum lines and an electrical connector(2 wires)

There will also be an EVAP pressure sensor, it can be near the charcoal canister or back at the gas tank, this varied by model year and engine
It tells computer IF vacuum solenoid is opening and IF the EVAP system/gas tank is holding negative pressure that the applied vacuum causes.

 

[nobbyv]

RonD, thanks for the reply. The good news is that the one that runs to the intake manifold area is intact. It's the one that ultimately runs to the fuel tank that's broken. But I can't tell how it gets back there: does it simply just drop down underneath the truck and run along the frame or something? Or is there some sort of "hand-off" where it transitions through the firewall, and then back?

 

[RonD]

It runs to the gas tank, with fuel lines, in the frame rail

No part of EVAP vacuum system is in the cab

 

[Mark_88]

Yes, as stated it's pretty much a straight run from the valve to the tank via the frame rail. It is typically (on my 96) a hard plastic piece that is very tough and resists rotting so not much to do other than nip the ends and make sure they are snug fit.

Mine did not run behind the engine or even close to it other than the one that came from the valve to the intake vacuum. From there it went across to the driver side fender and over to the purge canister. The line should run from the fuel tank to the canister by the rad (or wherever they put it in 97)...to the valve, then to the intake.

 

[nobbyv]

Thanks guys, I'll climb under there again tomorrow and check it out. Happy new year!

 

[irishmcirish]

I have the same issue on my 97 but the front pressure line leading up the canister, just after my abs sensor under the drivers side, has completely rotted out. From what I've gathered so far in my search for the lines is that they are only sold as a single unit in conjunction with the fuel lines. Is it possible to replace my evap line with a soft line? I can't imagine that it holds that much pressure and I don't want to fork out a few hundred dollars and replace fuel lines I don't need to.

 

[irishmcirish]

Thanks guys, I'll climb under there again tomorrow and check it out. Happy new year!

The evap line runs from the top of the rear of the fuel tank below one of the bed sills, straight to the drivers side frame via a soft line then connects to a high pressure line that runs parallel to your fuel lines, both supply and return. They split at your abs mod below your drivers side door where your fuel lines run to your rails and the hard line continues towards the carbon canister where it's adapted again to a soft line. This is at least the set up for my 2.3l. I'm out in California on vacation right now but I don't think there's anything different routing wise between engine sizes according to my manual.

 

[Denisefwd93]

Welcome to TRS!
You could do something super silly and super easy, put a balloon on one end with rubber band and find the other end and Seaview can inflate the balloon and see if it stays inflated by plugging the other end.
This is a very Timely post because I have gas vapors in my engine compartment. (4.0 engine) The charcoal canister is on the left just below the battery the Caps are missing off the canister and I probably have a bad valve which is also near the battery which is also more stuff that just got added to my " list"
Please report back so many the threads and discussions we never hear back on the solution success or fail.

 

[tomw]

There is little pressure. You can use any line that is fuel resistant. Patch the hard plastic with slip on pieces of rubber tubing, or replace the whole thing. It does not matter as long as it is sealed.
tom