Removing the EGR valve 96 Conti.

[k4uth1]

Well here is the next problem. How to loosen the flare nut from the bottom of the EGR valve. I cain't get a wrench on it or a pair of vise grips. Do you have to take the other end at the exhaust manifold off to remove the thing. And can you get to that without removing the exhaust pipe connection. Help!!
Thanks, Tom

[kr98664]

Dear Tom,

Is this related to your other post about the Service Engine light?

I recently replaced my EGR valve. It was not always shutting off at idle, but not enough to trip a fault with the computer.

To access the big flare nut, I visited my local discount store and bought the best $3 Chinese open-end wrench I could find. I remember my EGR valve required a 1-1/16" wrench, which was different than specified in the manual. (I don't know if the manual was wrong, or if there were two different sizes used.)

With an acetylene torch, I heated and bent the wrench to fit. I bent a right angle about 1" from the wrench head. When I put the custom wrench on the flare nut, I was able to grab the upright portion of wrench with a big combination wrench and turn the nut.

Alternately, you could purchase a crowsfoot wrench of the proper size and use a breaker bar and long extension.

Changing the valve was quite easy with the right tool. Just doublecheck what size wrench is needed due to the discrepency with the size listed in the manual.

Karl w/ a '96 Continental

[k4uth1]

Thanks Karl, Well I have read that you should clean the groove where the EGR mates to the intake manifold. So yes this is related to the Check Engine problem. I am just trying what I can to make sure all is like it should be. I am also checking for any vaccum leaks and all hoses and other connections. I appreciate your ideas on the wrench. And yes mine is also 1 1/16 in. I have a 1 inch so guess I will try to find a Chinese cheapee and bend it as you suggest. I'll let you know how it turns out. Thank You, Tom

[kr98664]

Dear Tom,

quote:I have read that you should clean the groove where the EGR mates to the intake manifold.

Oh, that is not necessary on the 4.6L in the Continental. Are you talking about this article?:
http://www.lincolnsonline.com/article15.html

The EGR passages are much different on the Continental engine. Instead of several fine, easily clogged passages, the Continental has a short single passage about 1/2" in diameter. With a small mirror and flashlight, you can peer down the throttle body and see this passage just below the throttle plate. (Have a helper hold the gas pedal down to open the throttle plate) I doubt you'd find much carbon build-up there, certainly not enough to clog such a big passage. You could save a lot of time and aggrevation by inspecting the passage this way.


Karl w/a '96 Continental

[k4uth1]

Hi Karl, Well I got the 1 1/16 wrench and even without bending it I was able to get the EGR valve off. And you are right there is no passage on the silly thing. So all that for nothing, but I am learning a lot about the engine. I've got enough parts removed to see all the vaccum lines etc. There is a rubber "T" in the lines that looks a little dry-rotted. Well at least I am eliminating things. I will put things back and look at the Oxy sensors and their connectors. I have yet to find a corroded connector. By the way, what is the module between the left shock tower and the firewall. It has a fairly large connector. I found the EEC module in the middle of the firewall and it looks OK. Thanks for all you suggestions and I still welcome any other ideas to the P1131 and 1151 codes. Tom, B'ham AL

[kr98664]

quote:what is the module between the left shock tower and the firewall. It has a fairly large connector.

Are you talking about the driver's side shock tower? The cruise control servo sits on the inboard side of the shock tower, immediately aft of the battery and partially over the brake master cylinder. On my '96, there is nothing in the gap between the firewall and the aft side of the shock tower. My car doesn't have traction control, so perhaps that is the mystery item.


Karl w/ a '96 Continental

[k4uth1]

Hey Karl, Yes, my car does have traction control. So maybe that is what it is. Well I am going to put it all back together this afternoon and see what kind of codes I get. I will check the Oxy sensors and their connections next. Will let you know what it turns out to be. Thanks Again for all your help. Tom

[kr98664]

Dear Tom,

quote:Well I am going to put it all back together this afternoon and see what kind of codes I get. I will check the Oxy sensors and their connections next.

Looking throught the diagnostic manual, the next thing to check (after unmetered air to the intake) is the fuel pressure. Considering both banks are seeing the same thing, I'd search for a common source. While it is still possible to have two O2 sensors fail at or near the same time (silicone contamination comes to mind) I'd rate that as less likely.

The factory diagnostic manual is pretty good. While we civilians can't run every last little test without some fancy test equipment, it is possible to extrapolate some results and make intelligent guesses for others. I was able to cure a nagging misfire problem with little more than the factory manual, a code reader (wish I'd sprung for a scanner, which reads sensor data in addition to displaying fault codes) and a digital voltmeter.

With that said, I must warn you I'm prone to testing and retesting potential faults. Whenever possible, I like to confirm faults and then proceed from there. I'm very averse to throwing parts (and money) at a problem until it goes away. I might drive somebody crazy who'd prefer to gamble on a likely part and see what happens. There are pros and cons to both methods.

Blah, blah, blah, enough of that. Remember, I'm not a professional Lincoln mechanic and don't even play one on TV. However, I would suggest following the factory diagnostic flowchart as much as possible. (I picked up this 4" thick book for about $20 on eBay. They show up from time to time and tend to go cheaply because they tend to scare off non-professional mechanics. Many shadtree-ers think they can't work on these cars so never bother investing in manuals.)

The next item in the flowchart is the fuel pressure. If it were low, say from a faulty pump or clogged filter, the computer would have no way of knowing. The injectors are pulsed by the computer, which expects the fuel to be available at a certain pressure. If the pressure is low (which causes a drop-off in flow from the injectors and the resulting lean condition as sensed by the O2 sensors), the computer responds by commanding increased pulse width (more fuel flow) from the injectors. In this instance, the computer is not smart enough to know fuel pressure is low because it in not monitored. Something as simple as a partially clogged fuel filter could be all that is at fault.

I suppose if you wanted to try, you could simply change the fuel filter and see what happens. That's a routine maintenance item and you wouldn't really be wasting any money if it was not at fault. However, the pump itself could be the problem or a kinked line or who knows what. A simple pressure test would reveal all of this in mere minutes.

The test is very simple. At the front passenger side of the fuel rails (look under the appearance cover for a chromed pipe feeding all 8 injectors) there is a test fitting. It has a valve inside like a tire's valve stem. The tester screws on to the fitting and depresses the core so fuel pressure can be sampled.

Turn on the key (without starting yet) and fuel pressure should quickly build up to somewhere the 30-45 psi range. A fuel pressure regulator (on the fuel rail towards the rear of the engine) senses intake manifold vacuum and adjusts the fuel pressure accordingly. Start up the engine and when engine load is high (revved up, low vacuum) the fuel pressure should be high, around 45 psi. When engine load is light (idling, high vacuum) fuel pressure should be around 30 psi.

If within specs, the next test is to shut off the engine and observe the pressure reading. It should not decay more than 5 psi within one minute. If the pressure decay exceeds this rate, then further troubleshooting of that system is warranted. It could be an injector(s) leaking or the fuel pressure regulator itself bleeding back down.

Also, check the vacuum line feeding the fuel pressure regulator for any signs of fuel inside. That would indicated a leaking diaphragm inside the fuel pressure regulator.

Good luck with the troubleshooting. At first, I was a bit intimidated by such a high-tech engine but after learning as much as I could, I've found it VERY simple to work on them. A different mindset is required compared to older engines, that's all.


Karl w/ a '96 Continental