help with P0420 please

after reprogramming the wifes trailblazer with the the tune i listed on another thread in this forum, i finally got around to putting the cold-air K&N intake in and redoing the exhaust.

i cut out the cat & everything behind it (there were some nasty crimps in the tailpipe). i then replaced everything with 3" including a 3" magnaflow muffler.(the post cat O2 sensor is still wired up and in place)
Sounds awesome (the wife hates it & i will be adding a 3" resonator where the cat used to be to bring down some of the in-cab drone)

I thought i had turned off all the switching in the first tune to eliminate any codes thrown by removing the cat, but i guess not.

i keep getting P0420 codes, what am i missing????

here is my latest tune

Ill look at it later tonight when I have a few mins. Why are you using the post-cat O2 without a CAT? Its not going to do anything AFAIK without a cat being there... And you are going to want to play with spark and camshaft settings with that exhaust, believe me I had a 3" catback and lost a ton of low-end tq which we already have too little of. Got the Magnaflow catback and got all my power back without changing anything in my tune.

i realize the post cat O2 wont do anything, but i was worried that disconnecting it would throw its own set of codes. it was easier to just leave it where it was.

Well you didnt have P0420 turned off in the DTC Enable/Disable section, I turned it off plus another post cat O2 thing. That might help a little bit.

I changed a few other things that you might like, compare this one Im updating to the one you uploaded and see if you like the changes. Some like TCC PWM I havent had a chance to check, but other than that the changes are very nice. :)

ahh, thanks for the help
i see which ones i missed now.
everything looks good with the changes you made from what i can tell. ill try to get this new tune uploaded sat. Hopefully ill be able to do some logging & post my results.

i did some logging today and compared it to a log i did before the intake & exhaust changes. Just at a glance it looks like its probably running a little lean now, the knock retard is pulling more timing & more often than before. Im thinking of doing a +2% increase across the board to the VE tables to up the fueling a little. Ill probably do some runs with the wideband O2 later on.

No prob man, Im just happy to help. Dont know much about other engines and cant really do much besides general changes for anything but the LL8.

Id go ahead and do that VE change, exhaust+CAI means you should be running a little leaner from the extra air from the CAI. I wish there was a way to desensitize the knock sensors, with no cat and 3" all the way back you are probably getting a bunch of false knock.

here is my latest tune & log file.
the transmission feels better with the changes you made.
I increased the VE tables 2% @ 1300rpm+ & 30%+ load(my initial adjustment right across the board was giving some problems)
I also pulled some timing out of the spark tables just in the trouble areas.

Glad to hear you like it, you'd like the trans a ton better if you got a Vette servo in there as well. Mine shifts so firm now, I had to actually lower the 1-2 base pressure by about 10% because it was snapping my neck. :D

Those changes look good, if your engine likes it thats what counts. Every one is a little bit different. Does look like in that log that you're getting a bit of KR when you get into PE mode. Im pretty sure I get some too, havent figured out why yet. Here in a few weeks Ill be able to better figure that out.

Are you still getting the P0420 code now?

well, it set another P0420 code today :(
im going to go through all 3 diagnostic menus again from top to bottom and see if theres anything i can turn off in reference to O2 sensor 2

Hmmm, weird. Ill look through your tune again and see if there's something I missed as well..

Edit:
Theres
P0054 "HO2S Heater Resistance Bank 1 Sensor 2"
under DTC Enable/Disable that you might want to change to "Not Reported", but other than this one thats all I see thats is related to the Bank 2 O2 sensor that isnt already turned off.

ya, i switched that on the tune i made after my last post...

just pulled the P0420 codes out of it again today

Im thinking the switching isnt actualy doing what its supposed to.
possibly time for the EFI guys to check their code.

oops, heres the latest tune

does anyone from EFI actually read these forums for customer feedback?

Well Im stumped man, Ive heard of people killing the CAT DTCs on I6s before so this is puzzling. Im still catted as I pretty much have to be in WA, so I cant go run and test it.

EFILive does monitor the forums pretty regularly, just the P10s are GMs little bastard child and Im happy we actually have a way to tune them. I do have a wish list but the code is supposedly really hard to crack.

Its hard to narrow down if its a mis-labeled switch as another member suggested, although the thought has crossed my mind, as it doesnt come up right away. Sometimes its taken a couple of days and several runs for it to show up.

I am going to try an o2 sensor spacer when it arrives......this is supposed to take the back o2 out of the stream a little.....

In the Audi circle, people use spark plug defoulers(only on the post cat sensor) in order to trick the ECU when running a test pipe in place of the catalytic converter.think you have to drill the hole bigger on a defouler

http://i21.photobucket.com/albums/b2...o2cheat/12.jpg

let me know how it works out.

Last time i cleared the P0420 code it went allmost a week before popping up again. The wife said she was flogging it pretty hard when it came up this time.
This has me thinking if its related to the cat protection somehow....possibly the sensor is getting hotter than the computer thinks it should??

My next step actually was going to be to just clamp the sensor off to the side of the exhaust pipe or the hanger and see if that helped.

it has to be in the stream...already tried disconnecting it or hanging it to outside air connected

Quote:

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Originally Posted by ExtTB

I am going to try an o2 sensor spacer when it arrives......this is supposed to take the back o2 out of the stream a little.....

In the Audi circle, people use spark plug defoulers(only on the post cat sensor) in order to trick the ECU when running a test pipe in place of the catalytic converter.think you have to drill the hole bigger on a defouler

http://i21.photobucket.com/albums/b2...o2cheat/12.jpg

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Before having all the codes disabled in efilive i used one of the bungs they sell on ebay,

http://cgi.ebay.com/ebaymotors/UNIVE...spagenameZWDVW

they worked great, here's the list of codes i have disabled and NEVER got a code back, NEVER...

>>>>> P0137
>>>>> P0138
>>>>> P0140
>>>>> P0141
>>>>> P2A01
>>>>> P0420
>>>>> P0054

this disables all the monitoring of the 2nd o2 sensor,

same thing but the place I ordered it from hasnt delivered...so maybe ebay is the way...bought th efans and pigtails from there

Quote:

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Originally Posted by pjaneiro

Before having all the codes disabled in efilive i used one of the bungs they sell on ebay,
they worked great, here's the list of codes i have disabled and NEVER got a code back, NEVER...

>>>>> P0137
>>>>> P0138
>>>>> P0140
>>>>> P0141
>>>>> P2A01
>>>>> P0420
>>>>> P0054

this disables all the monitoring of the 2nd o2 sensor,

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check the tune i posted....i have all those turned off and still throwing codes

if i cant figure a way to do it on the programming properly ill try something physical.

Quote:

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Originally Posted by skneeland

check the tune i posted....i have all those turned off and still throwing codes

if i cant figure a way to do it on the programming properly ill try something physical.

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Are you setting the DTCs listed to "Not Reported"?

Quote:

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Originally Posted by dfe1

Are you setting the DTCs listed to "Not Reported"?

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yes
The tune is posted above, have a look, maybe im missing something

After some logging and checking codes yesterday it appears the code is popping due to the idle catalyst efficiency test.

I cant seem to find where to change test parameters on this OS :(

correct me if im wrong, this means the rear O2S arent getting hot enough, so ideas of moving them out of the stream a little with spacers would be redundant?

just a little update.

no thanks to EFI live, but i have found a solution.

On advice from some of of members here i tried the sparkplug anti-fouler (18mm) trick and after 2 weeks so far so good, no more check engine light.

$3 piece of hardware > $800 electronics

Quote:

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Originally Posted by skneeland

just a little update.

no thanks to EFI live, but i have found a solution.

On advice from some of of members here i tried the sparkplug anti-fouler (18mm) trick and after 2 weeks so far so good, no more check engine light.

$3 piece of hardware > $800 electronics

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If i were you i'd ask for a refund for the efli unit, that this is useless for the traiblazer pcm ever since the january updates, once you wrote your pcm with efi and the january update the pcm is screwy...i know i had to go see teh dealer so he could do a complete reflash from stock and then with hptuners ALL went good

Quote:

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Originally Posted by pjaneiro

If i were you i'd ask for a refund for the efli unit, that this is useless for the traiblazer pcm ever since the january updates, once you wrote your pcm with efi and the january update the pcm is screwy...i know i had to go see teh dealer so he could do a complete reflash from stock and then with hptuners ALL went good

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You guys are either way off the mark in what you're trying to do, or there's a hidden agenda behind your postings.
First point- EFILive is a tool, if you don't know how to use it, or are trying to use it to do something for which it was not designed, the problem lies with the user, not the tool. Also, most tools do not come with a baby-sitting service.
Second point- HPTuners is also a tool, albeit an inferior one. Maybe the dealer doing a complete reflash eliminated a problem created by previous modifications.
Third point- I have reflashed Trailblazer PCMs with the latest EFILive release with absolutely no problems.

Quote:

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Originally Posted by dfe1

You guys are either way off the mark in what you're trying to do, or there's a hidden agenda behind your postings.
First point- EFILive is a tool, if you don't know how to use it, or are trying to use it to do something for which it was not designed, the problem lies with the user, not the tool. Also, most tools do not come with a baby-sitting service.
Second point- HPTuners is also a tool, albeit an inferior one. Maybe the dealer doing a complete reflash eliminated a problem created by previous modifications.
Third point- I have reflashed Trailblazer PCMs with the latest EFILive release with absolutely no problems.

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1- I have no agenda,
2- I know how the tool works
3- because you don't have issues does not mean other don't, what year is your tb ? what revision is your pcm ? how do you use your unit ? what codes do you even disable ?

if you read the OP post, it's kinda hard to fuck it up when you just need to click on a code change it to disabled and then do write....so if you are telling me that the OP and myself can't do that....well, you should come over one day and see my lab...really i wonder if you would know half the instruments i use in my daily job....so please don't say to anyone they don't know what they are doing BEFORE learning about the situation or actually reading on it a bit, check around the forum you will see A LOT of similar issues concerning th new cals...

but just stating facts, i currently own a 2002 trailblazer, everthing was fine until they did the january updates, as soon as they did that, I was unable to have accerleration, the truck would be in limbo when i went wot, and anything i would write to it would "seem ok" but was never actually written, i had posted this issue, even the speedometer tables on efi are wrong, efilive does not write to the proper ones, i know some 2003 and 2004 also have this issue,

Now this problem can only be solved by having the dealer reflash to stock, i tried using the cals from efi and just dumping my backup, stayed the same, the nes cals adresses something that the pcm does not like, if you go on a certain forum you will see a lot of people not happy with their product ever since the updates

it used to be fine before, my po420 was properly written off, i never had a light, my codes for the rest would not pop up, and then poof

My friend came over with his hptuners i bought a licence and read the pcm, to my surprise not only were some settings never written such as po420 but my fuel tables were at zero upon wot, so....

on another note, i went to efans, and if you look at efile half the cels hptuners have are not there, hptuner might not be a good tool in your eyes, but i know a few companies dealing in traiblazers that have completely abandoned it for such reasons...

BTW if you want screen shots of all the stuff hpt does and efi live i would be more than happy, or if you want a copy of all the emails that were sent between me and efi or the dealer doing my tunes stating that indeed they are also having trouble with the efilife ever since their cal updates....

the antifouler works great for me....50,000 miles without the 420....havent tried hp tuners.....many people sayit the best for the TB,,,,but I have mine working with efans thanks to a pcm signal I made...efi doesnt turn off all fan or exhaust errors period.220,000 miles of tuning my truck....even some programmers cant program all the pcm version this suv has....love my trailblazer but it always runs rich hence the 2004 changes and the fans suck if you high rev the engine....tranny made it 215,000 first one ever had make it past 100,000....efi did allow me to stiffen up the shifts allowing the clutches to last longer...3-4 gear shift is the one that just will keep getting worse with time....

I feel I have to step in here. I honestly love EFILive, Im stoked beyond belief to use it to tune my 08 TBSS but tuning my 02 P10 is challenging. First it doesnt use a normal SD or alpha-N, its a hybrid system (not EFILives fault) and its only used in a select year 02-05 GMT360s. That said, I have tuned 6 P10s in 2 years (not much of a business but hey everyone loves my tune) and only have 1 issue with 3 acceleration tables not working under 1 2002 OS. Everything else, Ive got 3 02s (2 with the latest OS that has the accel table prob, mine is mid-year and doesnt), 1 03, and 2 04s.

Ive heard HPT has more P10 tables, and that may be so but unfortunately I cant afford or justify the $400 for their basic tuning package because thats a cost Id have to pass on to my customers and until I come across an issue like the one above I wont. FWIW, Ive run my personal 02 (OS 12575262) and Ive completely disabled everything related to the fan clutch and run it for half a day without a fan just running software changes. Ran great (tested it 2x on different days in different temps) until it started getting too hot and I had to plug the fan back in and flash the normal tune back.

Glad to hear your opinion, Erik. I've seen your posts over the years, and you probably have spent more time reflashing the P10 than anyone else. My experiences with EFILive and my opinion of it are the same as yours-- it's absolutely kick-ass software, and in my experience, the folks at EFILive have always gone above and beyond to help customers.

If I stepped on anyone's toes with my comment about a "hidden agenda", my apologies, but it wouldn't be the first time that an HPT weenie tried an underhanded method of discrediting EFILive. Hell, I was even banned from LS1tech a few years ago (by the HPT-affiliated "moderators") for having the temerity to suggest that someone should use EFILive to solve a problem.

Personally, I have absolutely nothing to gain or lose from a person's decision to use a particular brand of tuning software. I just have a problem with low-lifes who make things up and try to discredit honest, reputable people because they have a competitive-- and in my opinion clearly superior-- product.

Quote:

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Originally Posted by dfe1

You guys are either way off the mark in what you're trying to do, or there's a hidden agenda behind your postings.
First point- EFILive is a tool, if you don't know how to use it, or are trying to use it to do something for which it was not designed, the problem lies with the user, not the tool. Also, most tools do not come with a baby-sitting service.
Second point- HPTuners is also a tool, albeit an inferior one. Maybe the dealer doing a complete reflash eliminated a problem created by previous modifications.
Third point- I have reflashed Trailblazer PCMs with the latest EFILive release with absolutely no problems.

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i have no hidden agenda, i neither work for, nor am affiliatied with HPT in any way. The coding for the PC10 pcm doesnt do what is says its supposed to do, plain and simple. Im pissed that the one thing i bought the software to do (retune my wifes TB after CAI and cat removal) it wont do properly and theres about zero chance of getting any further support for this application.

regarless, the problem is fixed and i dont see any need to pick up a copy of HPT anytime soon(the wife punches me every time i mention the words "turbo trailblazer")

General TB stuff here , I have a 06 and have tuned a few 06s , tuning on the P12 is just a little shy of the LS1 PCMs , shame the P12 is used in more than just the TB .
When the clutch fan goes out I will be looking to replace it with a e-fan setup if possible . I really wish there was more support for the P12 and TB in general , maybe when V8 is finished there will be more !
EFILive is a nice software and love the fact that you can list a table and it is easily found (B3702) just by entering the table number code and hit enter , easy lookup among a host of other great features .
I have a buddy that use HPTuners , he likes it , but he has also stated he wishes he had bought EFIlive instead of HPT . :secret:
dfe1 , have to say the flame came on there , poor guy just wanted/needed help . :angel_innocent:
Couple of years ago I , bitched and whined about TB support myself . :grin:
TBs where one great platform , terrible GM killed them off .
My $.02s

Quote:

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Originally Posted by Chevy366

dfe1 , have to say the flame came on there , poor guy just wanted/needed help . :angel_innocent:
Couple of years ago I , bitched and whined about TB support myself . :grin:
TBs where one great platform , terrible GM killed them off .
My $.02s

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Yeah, I may have jumped to an incorrect conclusion, but when someone complains about poor response from the EFILive crew, I get suspicious-- this forum is filled with responses from Paul and Ross, trying to help people with problems. As for anyone who doesn't want EFILive any more, it shouldn't be too hard to sell and at least get some money back.

Thanks dfe1, Im new to tuning and so Ive done lots of tiny changes over the last 3 years to get my TB tune to where it is now. I love it and those who have it do too, I tuned my friend's stock PCM with my custom setup and he says it makes a lot more useable power than the mail order tune he had. And he gets better gas mileage with 0 knock, but again we went for a few drives so I could tweak his truck a little here and there vs mail order just is a canned deal. Hell, with 3.42 gears (and 4WD), he gets 25mpg cruising at 65mph. Thats right, 25mpg! Repeatable, he doesnt have a DIC so its all hand calc'ed and this is over the past year. That is with 91 octane and 16" AT tires. I never drive at 65 for more than a few miles just because of the way seattle is setup, all my hwy is at 75-80 going east on I90 and Im happy to get ~20mpg. Wish it was better, but Ive also got 3.73 gears (big difference in rpms).


So back to tuning, Im going to ask my buddy with HPT to bring it to the TB meet Im having next saturday in Seattle and pull the tune on my 02. Then Ill really be able to see what HPT has/doesnt have for the P10s.