Throwing P0405 EGR code after custom tune

Sonic04GT · Post by **Sonic04GT** » Fri Nov 05, 2010 7:08 pm

Please don't be scared of my story size haha the main problem is in the first paragraph.

I have a 2004 Mustang GT that was dyno tuned on tuesday. During the tuning the car was throwing EGR code P0405 (EGR A Circuit Low) and he couldn't seem to get rid of it. He told me he just went ahead and shut the EGR off. I called him when I got home to verify and he said he shut the thing off twice, so it shouldn't be throwing any codes. The EGR system is untouched. DPFE sensor is getting 1 volt on 1 wire, 0 on the middle, and 5 volts on the 3rd wire, which I believe is normal. I even replaced the DPFE sensor today and still showing the same code. It isn't throwing a check engine light, but as soon as I start the car the code reappears.

Anybody had this happen before? Should I leave the EGR turned off or have him re-enable it and disable the code? Think the system will still work as it should, or would I see any downside to disabling it while everything is still in factory state? i.e. EGR not blocked off or deleted

Keep in mind we have no emissions testing in FL, so I have BBK Longtubes and a BBK Offroad H with the rear O2 sensors turned off according to him. I have always used MIL eliminators but I assume he turned them off as he said he did.

This was at Thunder Autosports in Boynton Beach, FL and done by a very reputable guy. I am taking the car back to him on monday to have another look but this just sounds weird.

I read on a truck forum that cleaning the O2 sensors could have effect. Now, a couple weeks ago we put Marvel Mystery Oil through the vacuum port on the plenum, maaaaaybe a bit too much. When I had my mufflers welded some was leaking out of the flow tubes. Not sure if that had any affect on sensors. I doubt it did but possible.

Occasionally I get a P0133 O2 Circuit Slow Response Bank 1 Sensor 1 but from what I hear, that's only because the O2 sensors are further away now with the longtubes and take longer to heat up. I didn't see that code until after the headers so it makes sense, just took a while to show up. I've seen it maybe 2 or 3 times in a couple of weeks. Not sure if it would have any affect but I didn't see the EGR code until tuning day. The O2 sensor code threw a MIL the first time I saw it before tuning, but didn't when I pulled the code today after the tune.

Can this 0133 code be compensated for or fixed with the custom tune? Why would it still show up but not trigger a MIL anymore? Read something about open/close loop making the sensors stay on longer so they can heat up to avoid this problem? Neither of these codes trigger a MIL.

Car put down 270/306 with bolt-ons so everything looks like it's working like it should, and it appears to drive fine. Had a little rough idling day after the tune, and some minor shaking at idle when I started the car but that went away after i gave it a little gas and the car warmed up. Still has the P1000 code so it hasn't ran through its readiness tests yet since the tune was installed.

I have attached the custom tune and original backup.

Thanks for any assistance.

Chris

Sonic04GT · Post by **Sonic04GT** » Wed Nov 10, 2010 4:05 pm

88 views and no help?

Post by **mikel** » Wed Nov 10, 2010 4:43 pm

Hmm.

EGR is disabled completely from what I see.

I made a change to the O2 transport delay tables that should help with the slow response codes.

FWIW, the MIL is shut off in the tune, he may have done that so you dont have the CEL on all the time, but if you want it turned back on, no prob.

Tell Steve to hit me up if he has iny questions on the EGR stuff.

Thanks

Sonic04GT · Post by **Sonic04GT** » Wed Nov 10, 2010 10:08 pm

mikel wrote:Hmm.

EGR is disabled completely from what I see.

I made a change to the O2 transport delay tables that should help with the slow response codes.

FWIW, the MIL is shut off in the tune, he may have done that so you dont have the CEL on all the time, but if you want it turned back on, no prob.

Tell Steve to hit me up if he has iny questions on the EGR stuff.

Thanks

Thanks alot for making that change Mike. So the MIL is shut off altogether huh? I guess that would make sense why I haven't been seeing it. What would cause it to be on all the time? Isn't there a way to turn off the specific codes that are likely to appear so that way if something important (granted if it was important id probably notice by the cars behavior) came up I would know via the CEL, so I can go pull the code.
Now, this is really puzzling me...why I am getting an EGR code if it is disabled...some kind of glitch?

Will I lose anything whatsoever if I install my factory tune back to see if the code goes away, then install the revised tune you just sent me?

Have you met Steve or do you just know him through the tuning world? Real good guy. I feel like I'm always bothering him with with this small stuff haha Told him I'd bring the car back to him this week, but I wanted to get some answers first before I put him on the spot where neither one of us really know what direction to go on the EGR situation.

Sonic04GT · Post by **Sonic04GT** » Mon Nov 15, 2010 4:21 pm

Erased the custom tune today, and restored the factory backup. Took the car about a mile, up to about 60mph in 4th gear and it isn't throwing any codes besides the P1000 Readiness. What gives? Is there any software that a consumer such as myself can use to read a tune, to see what was altered? I'm also curious what was adjusted as far as timing with the Thunder tune, since I switched over to 93, and should have been tuned for that. I'm a noob, and I know Steve knows what he's doing but I'm still curious.

Post by **mikel** » Mon Nov 15, 2010 4:26 pm

not sure about the egr code.

I imagine he left the MIL off so you did not have to see it for the EGR, although it should not be throwing that code.

I know Steve from being a local tuner to us, hes been by the shop a few times, really nice guy and he definitely has a good head on his shoulders for this stuff.

Sonic04GT · Post by **Sonic04GT** » Mon Nov 15, 2010 6:07 pm

Yeah that would make sense. Where are you guys located at?

I'm running out of ideas and people to consult on what to do with this. It obviously has something to do with the custom tune if it's not throwing any codes with the factory backup re-installed. I'm going to drive the car around a little bit more and see what happens.

Post by **mikel** » Mon Nov 15, 2010 7:10 pm

has Steve come up with any oither ideas?

Could be a short somewhere...

We are in Delray Beach, right down the street

Sonic04GT · Post by **Sonic04GT** » Tue Nov 16, 2010 2:04 pm

mikel wrote:has Steve come up with any oither ideas?

Could be a short somewhere...

We are in Delray Beach, right down the street

Very nice, I'm in West Palm. No I haven't gotten around to taking the car back to him yet. Wanted to gather as much info as I could on my own first.

If it was a short, I don't understand why it wouldn't trigger a CEL or throw a code with the factory backup installed, but as soon as I start my car with the Custom Tune the code immediately pops up. If I clear it it comes back seconds later.

Post by **mikel** » Tue Nov 16, 2010 2:06 pm

yeah, that is odd.

Sonic04GT · Post by **Sonic04GT** » Tue Nov 16, 2010 2:10 pm

mikel wrote:yeah, that is odd.

Are there any performance parameters related to the EGR that could have been modified to cause some kind of confusion in the computer? I'm going to put that custom tune in that you modified for me the other day and see if it pops back up after re-installing. Would it be too much for you to re-enable the EGR completely before I re-install the tune?

I'd rather have the EGR turned on if I'm not really getting any performance gains out of it being off and unblocked. May be easier to troubleshoot.

Sonic04GT · Post by **Sonic04GT** » Tue Nov 16, 2010 7:21 pm

I was just messing with my Predator after putting your modified tune into it. Original backup has already been restored to the car previously and the original custom tune erased. I seletected custom tune from the menu after uploading it and something popped up saying different tune selected, do you want to reset all parameters? I assume I just hit no and proceed to install the tune? Then it will create another factory backup?

Post by **mikel** » Wed Nov 17, 2010 1:19 pm

hit yes, that way any changes you made through the adjustable parameters will not be applied to the new tune.

Sonic04GT · Post by **Sonic04GT** » Wed Nov 17, 2010 1:44 pm

mikel wrote:hit yes, that way any changes you made through the adjustable parameters will not be applied to the new tune.

It didn't give me the option again when I went to install it, but I don't believe I made any changes.

Sonic04GT · Post by **Sonic04GT** » Mon Nov 22, 2010 12:32 pm

Is there any way that you guys can re-enable the EGR system in the tune that you adjusted the O2 delays on? It's beginning to be a pain trying to get the car back to him, and he says that's really all he can do anyway. This code/glitch is going to drive me crazy. I'm about to switch to the canned 93 Diablo Tune so I at least know everything is running 100%. I know my EGR works since it didn't produce a code running on the factory tune or the 93 Tune, but who knows what it's doing with this installed and a malfunction code showing up, other than nothing right now since it's turned off and physically UNblocked.