[KennyKaraoke]

98 SE

Rough idle (in park, nuetral, and drive; no difference), doesn't stall, but feels like it will. I have a low catalyst code I haven't gotten around to fixin' yet. It's definitely an exhaust leak, you can smell it. Could this be causing the rough idle? It runs perfectly while driving.
It's got new plugs, wires, fuel regulator. I saw in another thread about the EGR not closing properly. Any other ideas, I got some time tomorrow afternoon to work on her.

 

[EscorGo]

Run thru the previous posts. There are plenty of things to check while you are under the hood.

It's definitely an exhaust leak, you can smell it

An exhaust leak won't cause a rough idle - a vacuum leak will. If your exhaust smells bad you may be running rich or your cat may be bad.

 

[KennyKaraoke]

I searched and found that there are plenty of things to check, was just looking for maybe some kind of order, rather that hunting around. Though the vacuum leak does sound like a good place to start. Would it still run fine under load with the leak?

The exhaust doesn't smell bad, I just know it's a leak, cat or forward, that's causing the code.

 

[KennyKaraoke]

What is it?

Here is the problem, I think.
What do I got here? Anyway to drive without it (like to the auto parts store). Or do I wait until tomorrow?

 

[KennyKaraoke]

It won't run without it. It's a check valve of some sort, comes from a fitting after the throttle body, down to a pipe that splits it, one side goes into the air cleaner, which incidently was not connected (PO just changed air filter before I bought, must have forgot). Anyway, I can get the hose on the broken hose fitting side then what, maybe tape it up real good, electrical tape, I have the cloth high temp tape? The other side I can make a 3d model of an adapter to get back into the other hose. Perks of the job, ABS plastic printer access.
Sound good to any of ya?
See.

 

[KennyKaraoke]

It won't run without it. It's a check valve of some sort, comes from a fitting after the throttle body, down to a pipe that splits it, one side goes into the air cleaner, which incidently was not connected (PO just changed air filter before I bought, must have forgot). Anyway, I can get the hose on the broken hose fitting side then what, maybe tape it up real good, electrical tape, I have the cloth high temp tape? The other side I can make a 3d model of an adapter to get back into the other hose. Perks of the job, ABS plastic printer access.
Sound good to any of ya?
See.

 

[ethangsmith]

THAT is the source of your rough idle for sure! That is your PCV valve and tube that rotted apart. That is common with these cars. There is a second variation of the PCV tube that some cars had that put the PCV valve down at the bottom of the tube. That setup is much more reliable. Hit up Ford or your local junkyard for a new tube. It won't run very well at all with that massive of a vacuum leak.

 

[KennyKaraoke]

The valve itself is functional, to me it just looked like a simple check valve and since the replacements don't look the same...
Thanks for the ID.
I'll actually be near the boneyard Sat. to see if I can find the other arrangement then get a new PCV valve. In the meantime, I had some new hose laying around (just did a partial engine rebuild on my truck) and the adapter I made is working just fine.

 

[ethangsmith]

Good deal. I'm not sure what the deal is with the PCV rubber fittings on the Escorts, but they seem to rot really badly. It's almost as if Ford was not using the correct type of rubber. Your tube that you have is the worst for it too since the PCV valve is centered in the tube in a little rubber housing. The other setup has the valve down nearer to the engine and there is a lot less rubber parts with it. You may have to modify the tube a little to get it to fit, but it just requires some trimming of the hard plastic tube. No big deal.

 

[madmatt2024]

Temporarily plug the upper portion of the line until you can get it repaired. That should solve your idle problem for the time being.