[Markhaze]

P0401 code said Exhaust Gas Recirculation Flow Insufficent Detected.
P0430 code said Catatyst System Efficiency Below Threshold (Bank 2).
I've replaced the EGR valve which had a lot of carbon on it, but same codes came on. Does this mean I will need a new Catalytic converter?
Can anybody help?

 

[silvapain]

DPFE needs to be replaced. That is what controls the EGR valve opening and closing. On the EGR tube from the exhaust manifold, there are two rubber tubes that go to the DPFE. That will help you locate it. Replacing the DPFE should help with the Catalytic code, as well.

 

[drmurdoc]

I think there is a recall on the DPFE. At least there was on my 2000.

 

[sundarpn]

0401 - DPFE about 60 bucks, easy DIY. 5 min job

then other one i dunno. may be clean the o2 sensor...

 

[Racer X]

Ditto on the DPFE replacement. Might not cleat the Catalyst code, but it definitely will clear the EGR code.

 

[DrinkMore]

Before you go replacing stuff and wasting money - Like I did - it may be something a bit more simpler. If you look at your engine bay where the filter box is, follow it up to the "accordian" section and folow that up to the intake. There is a silver section between the tube and the intake. Remove that whole section. On the intake there is a big hole that allows the air in. Below and to the left is a ridge. It should be clear. However, mine was so filled with carbon, I did not notice it was there. After cleaning it out, my problem was solved.

Check that first. These sensors are pretty expensive.

 

[Racer X]

Originally posted by L0pan@Apr 12 2004, 02:14 PM
Before you go replacing stuff and wasting money - Like I did - it may be something a bit more simpler. If you look at your engine bay where the filter box is, follow it up to the "accordian" section and folow that up to the intake. There is a silver section between the tube and the intake. Remove that whole section. On the intake there is a big hole that allows the air in. Below and to the left is a ridge. It should be clear. However, mine was so filled with carbon, I did not notice it was there. After cleaning it out, my problem was solved.

Check that first. These sensors are pretty expensive.

Yeah, um...

A faulty or dirty MAF (the silver thing along the intake), or a dirty throttle body (the silver thing that is attached to the intake plenum) isn't going to throw a code for insufficient EGR flow. A faulty DPFE sensor, however, will.

 

[Markhaze]

Thankyou all for your help, the dealer had suggested I have a converter amongst other things with a cost near $2200.
I will try your suggestions first.

 

[KevinMarble]

IF you've got high miles on it, then I'll bet your Cats are going bad.. thus the P0430 DTC. Or, Possibly a downstream O2 Monitor If you're real lucky!

 

[atrib]

I had my DPFE sensor, and EGT solenoid replaced and 3 weeks later my SES light was on again for the catalytic converter, someone said that the DPFE can help when the catalytic code is on so i was wondering if anyone thought maybe the DPFE sensor that they put in could have been faulty?

 

[silvapain]

Is your car running bad? How many miles are on it? What year is it? If it's a GIII with the original cats, then they are probably going bad. It may be the cats, or it might be the downstream O2 sensors.

 

[XLSuruaT]

Originally posted by Markhaze@Apr 13 2004, 03:29 AM
Thankyou all for your help, the dealer had suggested I have a converter amongst other things with a cost near $2200.
I will try your suggestions first.

Dont know if its legal or not, but you could probably go to an exaust shop and have them chop off your old ones and replace them for half that price. The dealer is just trying to bend you over.

 

[maceslin]

Probably DPFE but in speaking from lots of experience a clogged throttle body port will cause the same codes.

You also need to check all the vacuum lines. I just had to replace a vacuum harness on mine for the same codes. THe harness had 9 fittings on it and cost $127 at the dealership, don't think AutoZone will carry

 

[Oldwolf]

Is this the DPFE?

Niehoff Ignition Egr Pressure Feedback Sensor

Or is this:

Niehoff Ignition Egr Vacuum Solenoid

 

[lynks]

I have 230 grand on my 97... funny thing is was a mess when i got it bank 1 was the trouble blown head gasket... #1 was pumping out water ... someone that had it before me never replaced the water pump they only threw in coughs.... stop leak... so when i got it was only a shaft... no impeller... re did the heads and all.. EGR was rust... replaced the EGR control.. now bank 2 is yipping cat not up to par.... funny thing is should had been bank 1 screaming with all the crap that went threw it.. sounds like this car for some reason had poor cats from the factory put in them...

 

[alwaysthinking]

QUOTE (Racer X @ Apr 12 2004, 02:54 PM) index.php?act=findpost&pid=45425

Originally posted by L0pan@Apr 12 2004, 02:14 PM
Before you go replacing stuff and wasting money - Like I did - it may be something a bit more simpler. If you look at your engine bay where the filter box is, follow it up to the "accordian" section and folow that up to the intake. There is a silver section between the tube and the intake. Remove that whole section. On the intake there is a big hole that allows the air in. Below and to the left is a ridge. It should be clear. However, mine was so filled with carbon, I did not notice it was there. After cleaning it out, my problem was solved.

Check that first. These sensors are pretty expensive.

Yeah, um...

A faulty or dirty MAF (the silver thing along the intake), or a dirty throttle body (the silver thing that is attached to the intake plenum) isn't going to throw a code for insufficient EGR flow. A faulty DPFE sensor, however, will.
[/b]

OK.... AFTER reading this post.... Racer X was correct..... 5 years later! To everyone throwing a p0401 code.... I personally removed the throttle body.... and where the gasket is, there is a ridge that was FULL OF CARBON..... i cleaned it out, reset the codes and that was that.... SO YES, RACER X HELPED ME FIX MY *SILVER THING THAT IS ATTACHED TO THE INTAKE PLENUM* lol

 

[JLShiffler]

I recently cleared my P0401 EGR insufficient code by clearing out the throttle body channel, packed full with oily carbon build up. My wagon is 139K and does consume oil, hence the oily carbon build up.

TRY this first, replacing the EGR TUBE was NOT easy. Cleaning a used EGR tube not easy either. Don't mess with the DPFE sensor untill you clean out the throttle body egr cavity and egr intake port hole. I had put the newer black DPFE sensor on in place of the metal one and no change. Remove the throttle valve and the gasket, it's a C shaped channel lower left side. Also remove the EGR valve to clean the port thoroghly. Hour job tops. DO THIS FIRST.

I also had P0171 & P0174 system too lean faults cleared by a PCV elbow that somehow developed a hole and was caving in and messing with the vacuum.

Still have a P0430 cat below threshold fault to tackle, inspection went out in June and just got a pull over and warning from the Man last Friday. Plan to cut open the cats and clean them with something sprayable and weld the cat ends back on, worth a try. If I can even get teh Y pipe off, looks like a nightmare.

 

[JLShiffler]

I recently cleared my P0401 EGR insufficient code by clearing out the throttle body channel, packed full with oily carbon build up. My wagon is 139K and does consume oil, hence the oily carbon build up.

TRY this first, replacing the EGR TUBE was NOT easy. Cleaning a used EGR tube not easy either. Don't mess with the DPFE sensor untill you clean out the throttle body egr cavity and egr intake port hole. I had put the newer black DPFE sensor on in place of the metal one and no change. Remove the throttle valve and the gasket, it's a C shaped channel lower left side. Also remove the EGR valve to clean the port thoroghly. Hour job tops. DO THIS FIRST.

I also had P0171 & P0174 system too lean faults cleared by a PCV elbow that somehow developed a hole and was caving in and messing with the vacuum.

Still have a P0430 cat below threshold fault to tackle, inspection went out in June and just got a pull over and warning from the Man last Friday. Plan to cut open the cats and clean them with something sprayable and weld the cat ends back on, worth a try. If I can even get teh Y pipe off, looks like a nightmare.

 

[JLShiffler]

YIPEEEEE!
CODES CLEARED !!!! Fault codes P0430 and P0420 both now CLEAR!! (cat efficiency below threshold)

I was just going to flush the cats with carb/choke cleaner and sea foam and use same O2 sensors to test if indeed one can clean converter but I broke one of the O2 sensors, the pre-cat from the exhaust manifold closest to the firewall.

WARNING: remove this O2 sensor, all others can be left in. You must remove the passanger windshield cow to reach down in. Removing the coil pack would help too, I didn't. You'll only be able to get an offset O2 wrench/socket on that O2 sensor (like a crows foot). There is not enough room for a standard (long) O2 sensor socket.

So plenty of PB Catalyst penetrating oil on the exhaust manifold studs & nuts helped them come off. SUGGESTION: get a 12mm tap to chase the holes when replacing studs. Also, the advance auto replacement studs did not have a nut flange to wrench on tight so perhaps try napa, carquest, pep boys, or a dealer to get proper studs with 15mm nut flange rather than the round flange with stud having an end slot/flat that you can't get a wrench on by the oil pan. Jerks.

So I cut out the 2 cats, visually they looked pretty good. Flushed with several cans of carb/choke cleaner then poured 3 bottles of sea foam through both directions several times and also filled it with the 2 cans worth of sea foam and held the ends closed while wearing nitrile gloves and rolled the cat around working the fluid to all spots. Then MIG welded the dual converter Y pipe all back together.

On ebay I found 4 O2 sensors for $20 each ,DY745, with only $14 shipping. Great deal.

Been driving a week and no fault codes pending. Going to try and get inspected and emmission tested soon. Been out since June. Not sure my OBD2 will pass since I basically have no first gear due to an AX4N tranny problem. Not sure if I can complete the OBD2 drive cycle if I keep switching down into 2nd gear when I stop. We'll see.

To sum up: replace all O2 sensors first, then try to flush/clean the cats if the new O2 sensors don't do the job. I'm not sure which, if not both solved my problem.

Hope this helps somone out.

 

[JLShiffler]

Just an update, driving since Sunday night and no codes returning.