Constant Code problem mysteriously vanished!

[black mamba1]

I have Tator built monster engine, ported, cam, etc. Tator built my engine for over 900 rwhp under forced induction..but once I got my car back, I kept throwing codes. Tator and Roe solved the problem w/ new programming, but I refused to use it cuz it sucked like 20 hp from my car.

Then all of a sudden, w/out warning, the codes vanished. All of them. I used to have to constantly clear these codes w/ a device on every start...now, for some strange reason, the codes have vanished. Car runs strong, the OBDII light still comes on during the check up on initial start...then, never comes back on. No matter how hard I run it.

I dont understand this. I can only think of two possibilities:

1. The warmer weather (but it still gets very cold at night, and still no codes) has helped bring the O2 sensors up to spec temp.

2. The car has "adapted" in some way to the new parameters??? (I know that sounds crazy).

But I was getting codes ranging from uneven bank firing, to O2 sensors not up to operating temp. Now I get none.

I am happy as hell, but I dont understand this...

Anyone got any ideas?

 

[RTTTTed]

Hopefully, the computer finally adjusted itself.

Ted

 

[Viper Specialty]

what codes...?

 

[plumcrazy]

tator will call it PFM (pure F'ing magic)

 

[black mamba1]

Ok, these were the most common codes:

PO 172: bank 1 too rich
PO 175: bank 2 too rich
PO 307: Cylinder 7 misfire

Now, none of them appear. I just dont understand why all of them would vanish like that. Does ambient temperatures affect the tune that much? Or are we dealing w/ a form of artificial intelligence here?

 

[mike & juli]

You KNOW the answer to this one: Call Chuck!!!! LOL...our advice we give everybody ELSE!!! ~juli

 

[Viper Specialty]

Here is what likely is happening:

You probably got the rich codes and the Misfire codes separately, right? Then one day, you happened to get a misfire along with a rich code? The rich codes will not reset the adaptives when cleared. However, a misfire code when coupled with a rich/lean bank will reset them. At some point, atmospheric pressure changes have likely caused the base fuel table to hop to a different cell on the manifold pressure base table, and temp changes likely skewed the fuel as well.

The problems stem from your camshaft not jiving with your base fuel tables, and "riding down the edge of the razor" so to speak on being acceptable to the computer.

Yes, it can be fixed. Permanently...and not with a VEC (if you want it done as well as possible). We can write a PCM flash to get rid of these problems sometime if you would like.

 

[black mamba1]

Here is what likely is happening:

You probably got the rich codes and the Misfire codes separately, right? Then one day, you happened to get a misfire along with a rich code? The rich codes will not reset the adaptives when cleared. However, a misfire code when coupled with a rich/lean bank will reset them. At some point, atmospheric pressure changes have likely caused the base fuel table to hop to a different cell on the manifold pressure base table, and temp changes likely skewed the fuel as well.

The problems stem from your camshaft not jiving with your base fuel tables, and "riding down the edge of the razor" so to speak on being acceptable to the computer.

Yes, it can be fixed. Permanently...and not with a VEC. We can write a PCM flash to get rid of these problems sometime if you would like.

Even though I have a Mechanical Eng. degree, I always feel like Fred Flintstone after reading one of your technical responses!! Man, you are sharp!

I am not sure what combination the codes came in. I know the last time I wrote about this (about 2 mos ago) someone asked which codes I was throwing. I went and checked, and all three of the above where there. But there were times I checked before and the "uneven bank firing code" had never been there, so that was new the last time I checked.

Thanks Dan! Hopefully this reply will also help others that experience this issue. You can fix all this when I drop my Viper off to you for the Paxton!

 

[PAvenomRT/10]

Dan,
Would you mind repeating what you said above so it is at least partially understandable?At first i thought you were kidding.
PAvenom RT/10

 

[black mamba1]

Dan,
Would you mind repeating what you said above so it is at least partially understandable?At first i thought you were kidding.
PAvenom RT/10

I'm glad I am not the only one whose head Dan is wayyyyyyy over!!

 

[Nader]

Dan I wish I understood what this meant... You should consider building rocket ships for a living. Oh wait you do...

Here is what likely is happening:

You probably got the rich codes and the Misfire codes separately, right? Then one day, you happened to get a misfire along with a rich code? The rich codes will not reset the adaptives when cleared. However, a misfire code when coupled with a rich/lean bank will reset them. At some point, atmospheric pressure changes have likely caused the base fuel table to hop to a different cell on the manifold pressure base table, and temp changes likely skewed the fuel as well.

The problems stem from your camshaft not jiving with your base fuel tables, and "riding down the edge of the razor" so to speak on being acceptable to the computer.

Yes, it can be fixed. Permanently...and not with a VEC. We can write a PCM flash to get rid of these problems sometime if you would like.

 

[DAMN YANKEE]

God, I hate it when this happens...good people asking for help, good people giving help, everybody feels good and then some other person says....

Ah.....No.....only partially correct. and what is correct won't make a hills bit of difference getting old Mamba to...well, mamba....NASA we have an issue.

But, having said that, lets have some fun so we all move forward on new rigs running BIG CAM Vipers with VECs.

First and foremost...Black Mamba, it is ALL going to be good news. But, you still have tuning work to get done here. You are NOT done tuning this rig with your VEC to get it to run right. You can flash if you want, but it wont help with your tune...it will get rid of the totally unimportant misfire code.

Now friends, the issue here can be best explained by splitting the problem in two pieces:

1. The rich issue.
2. The misfire issue.

Lets take the second one first. It may make a good man, Dan feel better as it requires flashing to fix the code issue. But having said that, lets be clear...flipping that code, for the reasons that are being stated is of absolutely no consequence whatsoever. Black Mamba (BM) your rig has a small routine in its code that is saying "hey, your pulses are coming too fast, I'm going to throw a code". The reason is your cam and it really doesn't make a hills bit of difference as everything is ok with your pulses. Hey, all us GEN2 guys have to deal with that code when we supercharge. Spin up too fast? Yep...code. Sometimes we swap out to an earlier PCM (that works) or we tape over the dash. BM, you can LIVE WITH THAT CODE. IF anything, it lets you know that you have got a really nice cam in there! The requirement to keep the misfire code from being thrown to make your rig run well? ZERO! Hate seeing any codes? Dan, is right...you can flash that one away...Can the VEC "fix" this code? Nope, no need to..its a benign software glitch in the PCM.

But the first issue...the rich issue...VEC is the right solution. Folks, it works just like this. Sean sees lots of heavy breathing rigs come into his shop with all sorts of monster cams. Some of these gems have a history of ruining....as in DOA...their O2 sensors in...ready?...under 5 minutes. Why? Too much fuel...way too much fuel....CRAZY too much fuel. Pop in a new set of O2s, turn on the rig...LET IT IDLE (just idle..nothing like what PLUM would do when he sits in his garage) and zzzzaaaaaappppp, its time for new O2 sensors. Sean told me of a story about a guy that ruined a set of new O2s getting the car from his garage to the trailer to Sean's.

Now BM, you your problem is not this bad...but this is your problem. So now why is this happening and why will a VEC completley and correctly and permanently and appropriately fix this issue? Why? well, it all goes back to this simple fact, covered in my video essays in the tuning section, if its about gas, degrees and air...well you are in VEC country. (Note folks, search for "golden tips" go to page four and read about injectors...that piece ends with a question "how do you tune when you are running LARGE injectors? or make other big changes?" ) The answer? "You use a VEC to turn down the injector pulses in Closed Loop so that your HUGE injectors work exactly like a stock injector". When you do this your adaptives get back into range, yours are failing to get the job done. Go Open Loop and those HUGE injectors go back to being...huge injectors. With his cams and such..old BM's injectors are runing too rich in Closed Loop.

The reason and solutions are as follows:

1. Old BM has LARGER than stock injectors.
2. Old BM has a great new cam.
3. Old BM has just about everything else too!

Lesson one :Read, gasp, next – the Log knows All

Next time you all read about an issue like this and there are no details, no endless logs, no little arrow thingies pointing at curves or tables filled with little red numbers…remember this:
Read, gasp, go on to the next thread. Why? Because the loggers know this one rule and we live by it “If you aren’t logging, you are screwed”. Simple and true. Log and tune to a razors edge or take your rig in. Both are totally excellent ways to deal with the problem. Old BM logs would be a thing of beauty. All those guys that post huge number here would wake up and start to write on these forums again. They would become overly animated as they explained exactly what you would need to do. All he would need to do is turn his rig on and let it idle. Turn it off, tune with his VEC and he is on his way to ending issue #1. Adaptives.....his problem is adaptive range.....old BM is out of his adaptive range.

Lesson two: 32.8 LESS FUEL – 32.8 MORE FUEL

Old MB gets into his rig and turns on his key. All hell breaks loose as his new monster engine kicks in. His engine warms up and goes into Closed Loop mode. What is that? It where all the various interactive sensors of his engine are listening to his engine and communicating with the PCM and making/changing his adaptives. Old MB’s engine is sucking on the gas…in idle, in closed loop…BIG TIME. His adaptives know this and start to cut back his injector’s pulse…more…more…more…more….and then gently as gently as when DAVE666 dances in a texas bar, it hits the wall…it has run out of adaptive range. Long term and short term fuel adaptive ranges in old BM viper is plus or minus 33% and that folks, just isn’t enough to grab this rig and throw it to the ground. “Hey PCM Listen UP, I have closed the spigot off all the friggin way and you still are too rich. Your going to get…a code…a rich code…a PO172 and a PO175” Old BM gets a code on his dash and says “Holy &#*&$#&*” But, being a true Vipernought, he drives his rig because, in his case, his tune isn’t that bad….he is not toasting O2 sensors. He throws his rig in gear and off he goes…..the codes remain. The first lesson? Adaptives by themselves can only effect 33% less and 33% more fuel in closed loop. After that folks….it all VEC country.

1. Trim all your cylinders back, say a good 2 mil seconds at idle and look your steady state injector trim by analyzing your active load cells (posted in red in your VEC fuel options page). Set them so that your back in the sweet spot. Get your adaptive back to as close to zero as you can, there is nothing about BM's Viper that is so special that those codes go away permanently.

2. LOG…log until your adaptives are back in line. Log until you drop, post your logs. Right now your fuel tables are close but no where near as close as they should be, you can make them perfect.

Lesson two: BIG CAMS – A commitment to learn to tune.

Its relatively easy to learn to tune your rig with an engine controller system like a VEC. Its almost fun. Add a new cam and it gets serious…Why? well not only will you need to attend to the duration of your injector pulses in closed loop mode but you are going to have to write some really cool and super funky fuel tables that make up for your cam cranking at idle and waiting until you go full throttle. You, sir are going to build Fuel Maps that make your rig perfect. Big cam....little vacuum.....HUGE GAS...at idle....or low RPM is your problem. Can it be done…hell yes. With a VEC? Hell yes. You can break that cam down in closed loop by RPM and adjust pulses and degrees until you get your 100 RPM as clean as your WOT rpm. Your fuel…perfect. Your timing, perfect. In Closed Loop in Open Loop. Right now your sucking on too much gas in low RPMs....

My favorite part of all this "Cause it sucked like 20hp from my car"....

 

[Viper Specialty]

Damn Yankee- a few things:

1. As you pointed out, Misfire has to be removed with a flash. It is due to the cam causing engine rotational speed changes beyond the parameters allowed by the stock program. But, did you also know that having a Misfire Code active in the PCM will cause the adaptives and other operations of the task manager to "freeze" or "Reset" depending on other circumstances? This will prevent the correct functionality of the adaptives and/or other systems.

2. The PCM is capable of working in MANY more vacuum/rpm cells than a VEC is capable of. The VEC allows only one add/remove cell per level, and then only a single percentage multiplier based on RPM. The factory PCM has 16 RPM levels, multiplied by 9 vacuum points EACH, for a total of 144 load cells for a base map. On top of that, it has RPM multipliers specifically for WOT active independantly of closed loop, as well as part-throttle tip-in maps- and the multitude of other maps for tamp, coolant, idle, atmo, etc. The VEC will never be able to tune as engine as finely as a factory PCM can. Not to mention, the vacuum table and WOT points for a cammed car arent going to be even remotely similar to begin with. (This same argument applies to the timing tables as well)

3. The VEC lacks in vaccum/boost transitions, and when toying around with closed loop conditions with a VEC, especially when a blower is present (future) provides for the instance of "chasing tunes" as one tune, based on another, is skewed by ever changing conditions. Can it be done? sure. It is the best way. No. The factory PCM has adaptive tables, multiple adaptives depending on load. Just because you adjust for idle does not mean you are correct all the way through the tune- and in fact, may be throwing your higher RPM adaptives further out of whack just by changing the idle fueling indirectly with the VEC. On base fuel tables, you change ONLY the cell(s) you need to, in either direction, and at any point in the map.

4. The VEC, when added WITH a flash, is actually very efficient because it is operating in a single dimension only. The PCM handles all Vacuum and engine parameters, VEC adds fuel and pulls timing under boost, only in open loop. Simple. Flawless. Perfect.

5. The VEC does not like to scale large injectors, and will begin to get laggy as the injector size is increased. The ability to alter this at the base tables and eliminate any scaling done in the VEC increases the overall response time of the system.


Just some rambling off the top of my head. I have pushed the VEC's to their breaking points, I have learned what they are good at, and what they arent. VECs on cammed blower cars? There are better ways to do it. VECs with 96lb+ injectors? Forgeddaboutit. VECs on cars with extremely light flywheels and 70+ lb injectors? Not easily done. Using a VEC to tune closed loop on a big-cammed car? Not easy, tune chasing sure to ensue.

I am not by any means saying you are wrong, and it most certainly can be done with a VEC for the most part if you wanted to... But like building an engine; "good enough to work" and "done right" are very different things. I think you may be underestimating the complexity and/or abilities of the factory PCM and how exactly the narrow-band functionality of the JTEC controller works at the table level.

 

[Coloviper]

I guess I will ask the obvious question: Can you even feel a loss of 20 hp when you have 900 hp?

My seat of the pants answer tells me "no". Why don't you run with the program that clears all these things up but runs 880 hp? I seriously doubt you will miss that 20 hp in that range and it will give you some piece of mind.

My 06' Viper Coupe is stock but will be upgraded in the future with some bolt on boost kit, however from experience I can tell you that my 95 Saleen S351R with a 408 built forged stroker and a 12 psi straight gear cut Vortech was dynoing at 603 rwhp but was extremely tempermental to ambient conditions and throwing codes. We dialed in back a bit, dropped the boost to 8 psi, put the H-pipe and Hi-Flo cats back in and reprogrammed it, to not be so on the edge.

It now dynos at 576 rwhp and throws no codes at all with the prior heat problem fixed. In fact, at the last emissions test last year, it ran cleaner than a brand new Shelby GT-500. I do notice a slight drop in power, but with the added traction I can use third gear. Previously the first 3 gears were just wrought with excesive spinning no matter how it was peddled along, but I can drive it in ANY ambient condition now and I never have to worry about detonation, etc. it is rock solid and is just a much more enjoyable car to drive.

I know it does not answer your question, but I am just curious if that last 20 hp really matters in that extreme hp range you are already in?

 

[DAMN YANKEE]

Dan,

Many thanks for the reply. Well said, but, Im going to be useless in this discussion because Ive never gotten even close to crashing a VEC's ability to make a Viper run strong and clean. My guess is that Mamba just wants to not throw codes and get back his 20 hp :> He is still away from mapping/logging and asking questions that would lead me to believe that he is crapping out because of his engine control unit, whatever one he chooses to use, is not up to the task.

I like what you said in #4, interesting!

Ill see if I can get Sean in to answer the more complicated issues.

 

[Viper Specialty]

Dan,

Many thanks for the reply. Well said, but, Im going to be useless in this discussion because Ive never gotten even close to crashing a VEC's ability to make a Viper run strong and clean. My guess is that Mamba just wants to not throw codes and get back his 20 hp :> He is still away from mapping/logging and asking questions that would lead me to believe that he is crapping out because of his engine control unit, whatever one he chooses to use, is not up to the task.

I like what you said in #4, interesting!

Ill see if I can get Sean in to answer the more complicated issues.

Since you seem to be a "tune ******", I would advise picking up one of the "pro-racer" flash PCM programs now available. There is no better way to learn these things than to play with them yourself, on your own car. You will see how you can learn to move the functionality of your VEC into the PCM, reducing its load, as well as gain control of hundreds of other things you didnt have any control over before.

 

[DAMN YANKEE]

I've got to get you to move closer to NY. I just looked up where you are, do you need a passport or oxygen tanks up that far North?

 

[ViperTony]

Hey Dan Lessier, check your email. I sent you some questions about rockers & pushrods.

 

[Viper Specialty]

I've got to get you to move closer to NY. I just looked up where you are, do you need a passport or oxygen tanks up that far North?

LOL! na... no oxygen tanks required here.

Snow suites... maybe!

Are you sure you are looking at the right map...? We are slightly south of any NE states...maybe I should be asking you that question? haha!

 

[Viper Specialty]

Hey Dan Lessier, check your email. I sent you some questions about rockers & pushrods.

Got it... had it open earlier when my computer went flat line and forgot to re-open it out of the "read" folder. I will answer it in a few minutes....

 

[black mamba1]

Thanks guys for all this great information! I do want to reiterate the fact that I am no longer getting any codes, at all. Its been going on 3 days, no codes. Temps have ranged from 29 deg F to 74 deg F. And still no more codes.

So, it seems as if the reason I am no longer getting these codes after getting them daily for months is b/c I had a misfire that reset my adaptive values on my base fuel map to a range that is not outside of the PCM's +/-33% adjustment capability? If this is the case..what exactly do I have to fix?

Am I on the right track?

 

[Viper Specialty]

Thanks guys for all this great information! I do want to reiterate the fact that I am no longer getting any codes, at all. Its been going on 3 days, no codes. Temps have ranged from 29 deg F to 74 deg F. And still no more codes.

So, it seems as if the reason I am no longer getting these codes after getting them daily for months is b/c I had a misfire that reset my adaptive values on my base fuel map to a range that is not outside of the PCM's +/-33% adjustment capability? If this is the case..what exactly do I have to fix?

Am I on the right track?

The correct way to do it is to write new base maps for the PCM. You are likely operating in a set of circumstances that just hasnt popped a code yet. If its a higher RPM issue, it can take some time for it to reappear.

If you are not having any driveability issues now, and you really plan on having us put a blower on the car in the future, dont bother with it- we'll have to take care of it anyway at that point. If its going to be a long while or starts becoming a nuisance however, it may be worth fixing sooner.

 

[black mamba1]

The correct way to do it is to write new base maps for the PCM. You are likely operating in a set of circumstances that just hasnt popped a code yet. If its a higher RPM issue, it can take some time for it to reappear.

If you are not having any driveability issues now, and you really plan on having us put a blower on the car in the future, dont bother with it- we'll have to take care of it anyway at that point. If its going to be a long while or starts becoming a nuisance however, it may be worth fixing sooner.

Ok...cool!

 

[RTTTTed]

Thanks guys for all this great information! I do want to reiterate the fact that I am no longer getting any codes, at all. Its been going on 3 days, no codes. Temps have ranged from 29 deg F to 74 deg F. And still no more codes.

So, it seems as if the reason I am no longer getting these codes after getting them daily for months is b/c I had a misfire that reset my adaptive values on my base fuel map to a range that is not outside of the PCM's +/-33% adjustment capability? If this is the case..what exactly do I have to fix?

Am I on the right track?

I asked the Viper Tech why he had installed a 2006 PCM in my '01 GTS and he said that '06 was the only year that didn't include a misfire counter in the PCM.

Ted

 

[black mamba1]

I asked the Viper Tech why he had installed a 2006 PCM in my '01 GTS and he said that '06 was the only year that didn't include a misfire counter in the PCM.

Ted

Very interesting!

 

[Zan186]

Dan I wish I understood what this meant... You should consider building rocket ships for a living. Oh wait you do...

With Dan just nod your head and pretend you can comprehend what he is saying and then just do what he tells you !
And yes he does build rocket ships (on wheels).

 

[Viper Specialty]

I asked the Viper Tech why he had installed a 2006 PCM in my '01 GTS and he said that '06 was the only year that didn't include a misfire counter in the PCM.

Ted

Yes it does... I've popped that one myself. I have an 06 PCM in my car.

However, it is much more lenient than the older PCMs, likely not to pop misfire codes as it plays with the timing from the knock sensors.

But down to the question- are you sure you are running an 06 PCM in an 01? I would not expect the bus protocols to mesh, though I havent tried it. Perhaps you mean 96? They are much more lenient also. What color scheme is the PCM? Part Number?