Check Engine light insuffient flow to cat

Tim,

Most likely its your DPFE sensor, or EGR pressure pressure flow sensor.. They are known for goin bad and its about time the first one did on you.. If you go to the local autoparts store they should be able to get you a new one for around $50.00..

Ford Tech

Another problem that's just as common is plugged EGR passages in the intake manifold. Here's a link to a Tech article on cleaning them:

Both will set a code for insufficient EGR Flow and without propertroubleshooting, it can be hard to determine which is the actual problem. The 2 problems aren't related by cause and effect, one doesn't cause the other. But, if you change the DPFE, Murphys Law dictates the problem will actually be plugged EGR passages. Inversely, if you clean the passages, Murphy says the DPFE will soon fail also (10 minutes before emissions inspection). :( I would advise doing both due to the fact that both are very common and cleaning the passages can be done for the price of a gasket and a can of carb cleaner. You can try cleaning the passages first, but remember, the DPFE is a common failure item and it is 16 years old.

And after that dissertation, I realized the car is an '01. I was thinking '91. DOH, hand me that dunce cap Ford Tech, I'll be over in the corner. Ignore my response and replace the DPFE sensor.

Before I do that you can check out a post I made in the ford truck group about 2.3L timing belts.. LOL I jacked that one all to hell... I think its funny that they said the 2.5L wasnt produced after 01, but the WSM and PC/ED still list the engine in following years.. :(

Here FT, have some chips? It's a nice corner but I see some cracks. We gotta get the custodian on that...

I think its > funny that they said the 2.5L wasnt produced after 01, but the WSM and PC/ED > still list the engine in following years.. :( Hmm, I've seen the 2.5 listed through at least 04 (Ranger?). I've never seen one, but I left the business in 01 and went into IT. I'm still "involved" but I don't see the newer models like I used to at the dealership. I can back you up on the "listing" through 04 though.

FTE is a pretty "staunch" bunch when it comes to trucks and what they know about them. They will argue a point into the ground. Some know more than others. It's a pretty good group though. I visit often and post occasionally in the electrical and AC areas.

A little about myself: I'm originally from West Virginia. I are one, and know first hand that "we" Rednecks are really hard headed to the end and it's hard to prove different when "we" think "we" are right. "We" also tend to be very outspoken in "our" beliefs, right or wrong as long as "we" believe them to be true. Unfortunately many of "us" haven't been formally trained. Many Rednecks across the country drive Ford trucks, happily a majority of "us". Ford makes some of the toughest trucks in the US. Hard headed Rednecks, like me, love a tough truck. That truck happens to usually be a Ford. If "we" Rednecks were to congregate on the Internet in all of "our" stubbornness , where would it be? Hmmm...

There is no connection intended between this personal FYI and any previous comment in this post. ;)

Ummmm.... I might be "flat rate reading"... but I see "check engine light" and "insufficient flow to cat"..... There's a reference to changing the EGR valve....

Am I the only one that sees a problem here?

While changing the DPFE might fix most CELs on these units, there is a distinct lack of information....

Uhhh, yeah, I missed the "cat" in the title. I was seeing and thinking "insufficient EGR Flow". Likely due to his mention of the valve.

Thanks for the advice. I was going in that direction I already changed the egr pressure sensor and egr valve.. Next I will go with DPFE. Just seems like all we do now is parts change till we get it right. very sad time for back yard mechanics.

Thanks again Tim

Nope.

Insufficient flow to cat could mean a a busted catalyst tube, a rubber section or a broken connector for the stainless pieces. Perhaps not enough air getting in the cat to "catalyze" the exhaust gasses? Just a theory. My theory, which is mine...

Except that there are no trouble codes that translate to "insufficient flow to cat."

He could have a 'insufficient flow to EGR or 'catalyst inefficiency' code.

But, as stated, it doesn't make sense.

Yup, that's why OBD2 came with a standard set of codes, didn't see one in the OP.

OK not enough info I get that a lot. the code at auto zone was 401 or 404 sorry can't remember exact code

There doesn't seem to be any vacuum going to egr so it will not open .

However there is vacuum at throttle body when I attach direct vacuum to egr it stalls the car.

That made me change the egr solenoid.

it made no difference So I started to think maybe a bad solenoid put ohm meter on it and got conductivity.

The next vacuum part in the line would be DPFE EGR pressure sensor that's a $80 item.

Thanks again for the help this group is great I'm getting nothing from Chrysler group all my cars are dying at once.

No problem, you have vacuum, its just not getting routed through the solenoid to the EGR valve, probably because the computer won't open the EGR solenoid. One of the inputs to this system is the DPFE sensor, which measures backpressure between the exhaust and EGR inlet tube. This sensor combined with others tells the computer how to modulate the EGR valve open/part open/closed. In very basic laymen's terms at least.

"Insufficient EGR flow" is P0401, I've had this myself. A new DPFE can be had at a dealer for about $30, at least in 2004 for my 2000 Taurus. YMMV. Economies of scale might have had something to do with the low price since at the time Ford dealers were replacing hundreds per month, perhaps?

Takes five minutes to replace on my vehicle. If you're going to get this far into auto repair do yourself a favor and get a code scanner and an alldatadiy account, gives you the pinpoint tests to get a better idea how to chase these things down.