Bad EGR?

[Diameg]

A friend had his CEL on and was told by a dealership that it just needed to be cleaned. I don't know what error codes it was throwing.

Anyways, we cleaned the EGR passages out as it was completely blocked.
After putting it back together, he's still getting the CEL and the following codes:

335 (DPFE sensor voltage higher or lower than expected.)

326 (DPFE circuit voltage lower than expected.)

Would it be reasonable to assume that it is just a faulty EGR and he needs to replace it?

Thanks

 

[BlackOnBlackATX]

hey Mike, if i recall isnt the DPFE the gray box on the back of the intake? i think you need to replace that alltogether seeing as your code is not telling you that the valve is blocked, just that this sensor is out of whack. throw a new one on there and the code should go away. let us know how it goes.
Bob

 

[Hermyclaus]

If this is on the 94 or around that year, Did you check to see if the 2 hoses on the DPFE that couple to the EGR tubes are also clear of any buildup? And that the tubes going to the main part of the EGR tube are clear. I had a collasped rubber hose on the HI side of the PFE. If you are not getting a 332 code,(EGR not opening) then I too would think that it is the DPFE malfunctioning. Good luck. Chris

 

[Diameg]

Thanks guys.

Yes, this was a 95 ATX.

The 332 code did come up in the KOEO stored codes, but that doesn't surprise me as the 'nostrils' inside the intake were completely blocked, 100%.
We cleared all those ports out, and he's still getting the 335 and 326.

We did not check the 2 hoses from the DPFE to EGR tubing. He's going to change the DPFE module anyways, so I take it that's a good time to check those?
Hopefully the new module does the trick. R&R-ing the intake is such a pain!

 

[Off Road SHO]

If you erase your stored codes and find that you still get the 332 code of insufficient air flow, you might need to re-do the nostril passageway cleaning.

I just did the "cleaning of the nostrils" on my 95 ATX and found that the two holes that you can actually see through the throttle body opening is just a small part of the entire length. If you can imagine the letter "T" with a long tail. Kind of like this T_____ Now just connect the bottom of the T to the underline marks and you have a representation of how long the nostril passageway actually is.

There is an allen head screw directly below the nostrils on the outside of the "Y" in the bottom of the plenum and another one just behind the EGR valve. These plugs cover up the machined passages that were needed to connect the EGR mounting location with the nostril location.You can't get to the bottom one without taking the intake off, but the one near the firewall is accessible.

I mistakenly thought you could just spray carb and plenum cleaner into the EGR hole and it would be sucked into the passage and clean it out. Wrong! The cleaner did loosen a lot of soot and carbon but it all condensed on the coolest part of the passage, the nostril area and clogged it up big time.

I made up a foot long piece of brake line with a threaded fitting that would attach to my air chuck. About an inch from the end I put a 90 degree bend in it. This allowed me to insert it right through the wired open throttle plate and blow the gunk out of the nostrils. It worked so well that now I'm going to add a siphon tube to it so I can suck up some Berryman's with it. Then I will remove the allen head at the EGR and blow the air-Berryman's mix through the entire passageway. Yeah, that's the ticket!

Tom

 

[Diameg]

Tom,

Thanks for the info, but we thoroughly cleaned all the passageways out.
We took it totally apart, including those allen head screws, soaked it in concentrated carb cleaner, and totally washed them right out.

You're right though, it is important to clean those passageways out as well. There was a ton of crap in there.

Mike

 

[K-BL]

If u r needing a EGR in the end, I have one for sale with only 7k on it.


E-mail if interested
[email protected]


K-BL