melted PFE '95 Ford

I dont know if it's just me but what is the acronym for PFE?

because GM and Ford have their own names for stuff, and OBDII has universal names for things.

Sorry [I have to look them *all* up, so I don't know which ones are common knowledge & which aren't]

Pressure Feedback EGR. It is the little grey plastic thing that has a rubber hose going to the EGR pipe, and has a solenoid in it that turns the EGR valve on and off.

[A picture being worth 1000 words-- here's one down from my application, but otherwise identical] On mine it is separate from the EGR, but I see some in the manual that some are attached right to the EGR.

Jim

Or, Pressure Feedback Exhaust. On a 95, it's probably a DPFE, the "D: standing for Differential.

Can be plastic, can be pot metal, depending on application.

No solenoid that I've ever seen (haven't seen everything though).

Does the little hose that runs from the EGR passages to the module fit tightly? Mine had gotten loose and exhaust was blowing around it, melted everything. I had to go to the dealer for the hose, it's hi-temp silicon and cost more than the sensor at the parts place. It's been fine since. I have a '95 C-Vic with the 4.6 but maybe the hoses age the same...?...

Paul in Dayton

-snip-

I suppose-- since the E in EGR is for exhaust-- but my books all call it a Pressure Feedback EGR-- [Probst & 2 Chiltons]

Wouldn't that be one with the 2 hoses measuring 'up' & 'down' sides of an exhaust tube? Mine only has one. [and my 95 specific books are in the mail someplace]

My bad--- 'solenoid' was pre-coffee mis-speak for sensor.

But back to the original question--- would excessive heat in that area be caused by anything other than backpressure?

Jim

More than the sensor?! Which parts place? I'm going to get my next one there.

The hose *is* expensive as rubber hose goes-- $5 a foot at my dealer. [they had a part number for the 4inch piece, but I knew I'd need more so I bought 3 feet of it bulk-- the part was probably $15 in a box with a number.

The PFE was $70 from NAPA, though. I didn't price it at the dealer.

You make a point though-- I'll clamp the next one onto the PFE so if it comes apart it will be at the exhaust pipe end.

Jim

[snip]

Backpressure, lean mixture which burns hotter and slower. Go back and tee in your pressure gauge, tape it to the windshield and go on a test drive, if the BP exceeds 3psi, I'd fix the exhaust restriction. Make certain that your MAF sensor (if equiped) is clean, dirt on the MAF resistor wire can cause a lean running condition and not always set a code.

One trick I use on Fords is to splice in a length of 3/16" steel line between the exhaust tap and the sensor, the steel line dissapates heat better than the solid length of hose, plus it's a cheaper fix if there's enough hose left to make the ends.

When I replace Chrysler EGR valves/transducers/solenoids, I save the Silicone rubber hose to use for fixing Fords, saves my customers a bunch versus the obscene price Ford charges for their hose package.

While I don't kow the answer to this question in general yet-- as it pertains to my Taurus, I'm pretty sure that was the problem.

Hoping it was an obstruction in the flex pipe that joins the 2 cats & crossover pipe to my exhaust, I cut those bolts and dropped the exhaust. No joy-- that piece is intact & the car still has high rpm cutout.

But before I bolted it back up I looked in the end with a flashlight-- Great gobs of converter core, Batman! I shop-vacuumed about a quart of them out of the first couple feet of pipe. The largest was just big enough to clog the exhaust. . . until it rolled over. Thus the coming and going symptoms.

Now the question of the hour is. . . What made the cat[s] fail? This thing has 2 cats & the whole setup is $309. [#4663 at

] I'd hate to pay that without fixing the problem, if there was one that caused this & it isn't just 'one of those things' that happens. [I don't weld, so cutting out a bad one & welding in a single isn't an option. By the time I paid someone else to do it, I might as well just go with the factory setup & had 2 new cats.]

thanks, Jim

OK-- As you see in another post, I located the source of the backpressure-- and now I want to be sure that I'm not throwing my money away on new cats. [all relative, I know. . . after all it is* a Taurus. . . but anyway] About the lean mixture, sounds like something that could have made the ceramic in the cats start to melt in the first place.

In replacing the parts that I have so far-- I know that the EGR wasn't working right for a few thousand miles as I could hear that leak long before it broke through the cloth coating so I could see it.

From the condition of the Canister purge solenoid, I'm also sure that wasn't working for a while-- it was locked into a 1/2 open position.

As recently as 1000 miles or so ago, though there didn't appear to be a severely lean condition judging from the condition of the plugs. Original autolites- in pretty good shape.

Is there something else I should check before I replace the catalytic converters?

I found the restriction-- pieces of ceramic making their way through the system.

Brand new MAF sensor.

Hopefully this 'super tuneup' will keep things cool in that region for many more miles. [I only want another 50-60k out of it.]

I was a little shocked at $5 a foot for it bulk-- How much is the 'part' in a box. Does it consist of more than just the 4" piece of hose?

When I asked for 3 feet of that hose, the parts guy at my dealer said he had a part number. . . but then when he looked at the price per foot, he looked shocked [that it was so low?] and cut me off 3 feet.

Jim

Jim, Could be worse, my 95 Merc Mystique has 3 cats. They went out a 60 k. Bob

Definitely worse. Did you just replace them-- or did you find an underlying cause for their failure? 60K would really bother me. At 110K it is only my ancient Scotch blood which makes me regret spending $300 more on this otherwise low-maintanance car. [I bought it new & the only thing that hasn't been just normal maintenance was the failure of the AC a couple years ago. I said 'No thanks' to a $1000 bill for something I use 2-3 times a year.]

I just replaced the muffler last year-- and I'll replace a perfectly good exhaust pipe this year just because it will make the cat job easier. [and this is in NY in a county that loves to use road salt. They must last forever in Florida]

Jim

If the substrate -is- actually melted, you need to check for causes of over fueling and missfire. A cat won't get hot enough to melt without two things: fuel and oxygen. A missfire provides both thru its inhereant action, overfueling provides one, the broken EGR tube -could- provide the other. The oxygen sensor when monitored with a DVOM is an excellent method to verify fuel control.

Since the EGR displaces air/fuel mixture, being inoperative could have played a role.

Another possible contributor.

Autolites weren't original to a Ford Taurus, Motorcraft was the OEM brand sparkplug.

Running both the KOEO and KOER self tests would be prudent. I don't recall what model year yours is, so watching live serial data via a scan tool -may- be an option if it's newer than 93 or so.

Excellent.

Ouch.

In my book, PFEs, DPFEs and their associated plumbing are maintanance items, i.e., they'll fail eventually due to the harsh environment they operate in. Then again, Ford has always had a hard time with their EGR schemes.

A 4" or 6" length sold in a plastic bag, IIRC the price I pay is around $10. Haven't needed to buy any for a while, especially since I now scrounge the hose off of failed Chrysler EGR assys.

Sounds like you sort of won that round. ;-)

Gee. I wish I could have gotten hose that way. I was fixing mine after the dealer closed. I hit every parts store in NE Dayton, I think. Nobody had anything that would take the heat. I had to wait until Monday to get it at the dealer ...$$$...

I think I got the sensor at AutoZone... It was a little while ago and my memory is fuzzy, but it has been fine since I fixed it.

Paul in Dayton

-snip-

NAPA & Advance Auto were both over $70. Autozone had hte $70 one, but they also had a generic one for $40. [and oddly enough, Advance Auto & Autozone both call it a "Position Sensor EGR" - they have the cross reference to the right OEM #, or I'd have never had them pull one]

-snip-

Jim

every time I shop them for major parts I look on the web site first. There were several names for the part but only one was available for my car. Shopping for the throttle air bypass thingie was a hoot! I think there are

5 names for it...

Paul