Has anyone experienced poor running issues, like a miss and check engine light with this vacuum leak?

 

Typically there shouldn't be any misses or CEL's triggered by this single leak.

No one here has ever reported a CEL and it being caused by this sort of vacuum issue.

The PCV is another issue though----that tends to show "lean bank 1, bank 2" condition.

 

Nope on the PCV, I pulled the functioning unit, replaced it with a new one, removed the entire tubing, checked it, replaced the rubber elbow with absolutely no change, as well as the intake tubing, MAF, and cleaned the TB & MAF while at it, no change. I just know that engines in the past that suffer from a vacuum leak will miss, I'm tired of replacing parts, was hoping that this could be the reason for the other, after the replacement of the transmission I am at a point I can't walk away, but I can't afford pouring more money in it. If someone would give me $3500 for it, it would become their project, the transmission is well worth that, if you've priced replacing one.

 

Have you checked your exhaust? The engine needs to breath well and a plugged Catalyst converter will give the a lot of symptom that are assumed to be vaccum, transmission, or engine problems - not being able to pull a load up hills, shifting poorly and sometimes shifting up and down and making lots of noise at times, poor gas milage and the A/C was shifting to the floor when the engine went under load.
I thought was in the transmission -I took it in for an evaluation at a good shop (Cost me 30 bucks) He check the computer, took it for a ride and when he got out he said nothing wrong with the trans. It's the engine - it's not breathing right and the computer does not know what to tell the trans to do.
Had the cat replaced and no problems now.

 

Got 4 cats, it's saying lean on both sides, no way both sides are plugged, and if you saw how I drive it, it pulls hard, you can blow the doors off of vans it's size, but when you're cruising at low RPMs, it has a constant miss that is absent when you are ringing it's guts out.

 

Would the rear AC be affected by a vacuum leak too? Today my dash vents quit. Speed or engine load does not change things. I also noticed that I have no air from the rear vents. I was getting heat from the rear floor vents so I am thinking that the vacuum leak is affecting these too. It all worked on Friday when I used the van.

Leaning toward the check valve on tank in the fender well.

 

Heating seems to be the default condition with our systems. Chances are you'll find the vacuum servo itself has most likely fail for some reason. There is a blue plastic line running to that servo, its junction being (probably) visible low on the B-Pillar drivers side.

I'd test first for engine vacuum at that junction then attach a hand-held vacuum pump/gauge tool testing for the vacuum signal strength; if there's no vacuum that needs to be corrected.

Applying a vacuum signal to that junction will reveal whether the servo is defective or otherwise not working for some reason. If the vacuum introduction gets cold air flowing through the roof vents then you have an issue with vacuum being lost somewhere before that junction.

IF your front vents operate as designed the vacuum reservoir on the fender (good luck finding THAT! ) then it more strongly suggests something running towards the back unit is amiss.

If this doesn't make sense or is unclear I'll try to better describe it---let me know via PM maybe----don't wanna run this thread too far afield.

 

Thanks, I noticed that the rear vents were not working right on Thursday. Shut the van off and restarted and they came on. Dash was fine at that point. Seems to have developed into nothing working over a few days.

Will PM you for more info. This may be why the rear AC didn't feel as cold as the front too.

 

Hey guys - I have a 2006 E-350 doing same thing under load to defrost & then comes back to normal a/c vents once I top the hill or let off the gas. Anyone know where the vacuum resevoir & check valve are located on the 2oo6 ? Still above pass. side wheel well ? Thanks, Bill

 

Tonight I found two leaks. One in the black line above the blower motor under the hood. It was brittle where it sat on top the AC line. The other was the line at the reservoir in the wheel well. 3 inch piece of hose that what dry and loose. It fell off. Took just a couple minutes with a cutoff wheel to open it up. Replace that line and both my dash vents and the rear vents are working again. Best part is I spent no money yet. I will need to get something to seal the hole again. Plan to tack the metal back in place with the welder tomorrow. Need the van to pull the trailer to make a home depot run to get a playset.

Thanks for the help. The rear panels are actually not bad to remove. Also I now know what is under that little cover on the dash. I tested for vacuum there too. Was able to pull a vacuum on the blue line to the rear and move the door. I sucked and the 7 year old felt for air.

 

To date I've not seen or read of anyone actually finding that damn thing on one of our E-Series. Some have resorted to using a new reservoir grafted into the exiting under hood line eliminating the hidden factory part.

Here's a link I found very interesting and helpful: https://www.ford-trucks.com/forums/1...-problems.html

I don't have a spare 7 year old so instead bought a gently used Mity-Vac set!

A lot of heating/cooling issues on our later E-Series can be traced to the vacuum portion of it all. The only real problem most times is digging through all the trim and other parts just to repair or replace a line etc.

 

Fortunately the one was right under the hood. The other required a cutoff wheel in the grinder.

 

My guess is that it is likely in the same spot. I cut mine 97 open last night. The 3-4 inch longer hose had come loose. I think that happened on Sunday. Before then it was the switching back and forth.

Pretty much straight above the passenger tire. Slightly to the rear. about the 11:50 position.

 

Thanks much for the link JWA -I am gonna do that rather than hunt for the original parts.

 

That's the biggest time saving move you can make Pick'r, trust me on that!

Twice I've dismantled a lot of components inside and under the hood looking for that Loch Ness Monster of a never seen part---if I didn't know better I'd swear they just didn't exist!

Its odd it can be so easily and cheaply bypassed so maybe its a non-issue for anyone facing this repair and lucky enough to have found us here on FTE.