OK guys, I've got a vacuum leak at an O-ring where my air rail control goes through the intake manifold on my Ford Windstar. Sadly, Ford engineers didn't design the seals so they could be replaced so I'm looking at a $2200 repair for replacing the manifold and 8 hours of labor. No driving issues. Fuel mileage is still about the same but occasional surging at idle. Just turned 200K miles on the van and I want to make it to 300K. Any suggestions on a work around? I'm thinking an aerosol RTV sealant applied with the engine at about 2000 RPM or gobbing the hell out of it with some high temp silicone sealant. The actuator on the rail control doesn't engage until 3000 RPM so it rarely opens.
I have had this repair done to several of my Windstars over the years: manifold gaskets leaking. Seems to be very common on the Windstars. Maybe that is what it is. Wasn't near that amount. Usually around $500 or so. I would shop around.
I think hes talking about the active intake, short runner valve, manifold tuning valve Or what ever Ford calls it. I assume Ford uses some sort of a split runner valve same as our Chryslers. I've done a few on Chryslers and its a new manifold. Hopefully we have a ford tech on here???
I think Ford calls it the Intake Manifold Rail. It's a baffle that opens up at 3000 RPM to allow for more air flow. The rail is controlled by a single electric actuator that controls both banks. Using carb cleaner I've determined that the leak isn't with the upper manifold gasket but is actually where the front bank actuator arm goes through the seal on the end of the intake manifold. Permatex sells an aerosol RTV sealant that I'm thinking about spraying on that seal to see if I can seal it up. I've also seen some comments from others on some Windstar related forums that have just disconnected the whole mess and live with having lower performance when they're over 3000 RPM . (I bet 99% if of my driving is less than 3000 RPM). If I did that I'd use some kind of high temp sealer to just gob the heck out of and see if I can make 300K miles without any PITA check engine light coming on. If it were as simple as my little straight six 200!
If you disable the IMRC (Intake Manifold Runner Control)...It will trip the CHK ENG light first time you stab the throttle...We generally just replace the upper intake since the bushing is not servicable. You can try the RTV method, be certain it has set up completely before you run the engine.( I have seen em suck the RTV in on deceleration) Good luck!!!
Mavman72's hit it on the nose. The front IMRC bushing is the culprit here. Any other suggestions besides the aerosol RTV sealant I mentioned you think might work?
DON'T use sealant. Just to make sure I understand where you are talking about the leak is; are you referring to where the IMRC (intake manifold runner control) shaft comes out of the passenger side of the lower(metal) portion of the intake? if so, this will show a leak and is normal unless there is an audible hiss(huge leak) from this area as verified by stethoscope. Propane enrichment will also indicate a leak but the system is designed for a small amount of leakage due to clearance in the runner shaft bearings (metal seals). Also what year is your windstar? 96-98 have a different IMRC system than 99-03 and have different issues/fixes. The plastic piece directly on top of the metal portion has bushed retaining bolts to attach it to the lower and are almost always leaking. Ford sells these bolts separately with the grommets attached. this only applies to the 99-03 models. what was your actual problem? check engine light or driveability issues, both? Do a google search on tsb 03-16-01 and that should give you the info you need. You don't have to replace the valve cover as stated unless you have excessive oil in the intake and you do have to have the PCM reflashed by the dealer. also make sure you inspect the rods that attach the IMRC controller to the IMRC levers on the intake. These little plastic bushings are notorious for falling off as well and are available for replacement as well. btw: you will need to have the PCM reprogrammed after you perform the fixes. the later calibration changes the sensitivity of the fuel tables so that they aren't as likely to generate the P0171,P0174. If it's just a problem with the IMRC itself, then you won't have to do the TSB
The windstar is a 2001 model LX, 3.8L The clue something was going on is surging (itermittent) at idle. It always "settles down" and when it occurs it's always with a warm start. No codes have been tripped. What alarmed me the other day was a bona fide "won't start" 30 minutes after a 1 hour low RPM city drive. My third start attempt was successful using the gas pedal but it was missing horribly and smoothed out after about 5-8 seconds of working the throttle. About a year ago I was experiencing the "lean error code" on the front bank related to the IMRC and replaced a broken notorious nylon bushing that holds the actuator arm to the runner assembly. Fortunately there is no loud hiss in the area but I do get a change in idle characteristics when carb cleaner is sprayed around the bushing area of the runner control. Thanks in advance for everyone's input.
I would suspect the intake spacer grommets and gaskets for the running problem and lean codes if nothing else is obvious especially if they've never been replaced. The replacements are of a different material and slightly larger.(you'll see when you disassemble it the old ones usually fall out. they have to fit tightly to seal) I don't know what to think about the missing concern unless that was taken care of with the IMRC bushing repair. I have never improved anything by replacing the lower for leakage around the IMRC shaft bearings tho. The little vacuum hose that goes to the regulator is prone to swelling as well and air can leak around it. that part should be listed in the tsb I mentioned before. It's not a difficult repair so the costs shouldn't be outrageous but I would try to stick with factory parts as far as the gaskets and bolt/grommets are concerned. btw: when the engine is cold, spray a light mist of brake clean along the line between the plastic and metal portion of the intake and if the idle quality/speed is affected they are probably leaking. The leak tends to disappear as the engine warms up. also, some of the PCM calibration updates take care of certain starting issues as well. Ford currently seems to add several "fixes" on one update and they aren't very forthcoming with that info at times. hope this helps
