From what I've read here on the boards, 2004.5 and up G35's T'netics ST's see these codes like it's meant to be. I think most owners ignore the issue.

Well, I talked to Ed at turbonetics and they seem to have no intention on providing a remedy for this situation. He stated "...it's a rare occurance that I haven't heard of...check the fuel pressure and for boost leaks...there is nothing we can do to fix it..."

I have installed more turbonetics VQ ST kits than I can count. I go above and beyond with what they supply in the kit. I have repaired Turbonetics ST kits installed from other shops that have issues. I know the kit well. The car in question that I'm having issues with is holding 9psi. AFR's are in the high 11's under full load. No other mods are done to the engine that would affect the kit. The car makes 360 WHP through the catted mid-pipe. Most T'netics ST kits make around 8. Maybe, just maybe, the fuel pump is part of the problem. I don't trust the Walbro GSS342's anyway. I can't see this being related, but I may check the pressure to be sure.

I've consulted Sam from GTM, Jermain from TurboXS, and Mike from AAM. They're all aware of this situation. It's pretty much concluded that it arises from a transitional state that the leading A/F sensors sees (very rich) and cannot compensate enough to trim to the target the ecu wants. The transitional state is a part throttle tip in rich condition where the MAF voltage increases with boost onset and the ecu dumps fuel from the larger than stock fuel injectors. The amout of fuel is too much for the ecu to trim and bring it back to target, thus the ecu throw a rich shift code (1274/1284).

Can this problem be fixed easily...no. Some may get lucky by switching the trailing O2 sensors, but I'm not convinced that they're even involved with these codes (according to the FSM). Somehow you have to eliminate the overly rich tip in condition. You can either trim the fuel map or change the target the ecu wants to see. In order to trim the fuel map, you need the flash hadware/software. In order to trim the fuel target, you may possibly be able to do via flash. Either way it's not cheap or a guaranteed fix. The light still may come on. Anytime you are tuning transitional states (atomosphere to boost) in fueling, it gets tedious/time consuming.

UTEC has variables that can let the end user/tuner choose when the ecu goes into open loop. When the ecu is in open loop, the A/F sensors go off line and all the fueling defaults to the tuned fuel map. So now the window for the A/F sensors is significantly reduced and the chance of the ecu maxing the trims probably won't occur. Therefore the code will be in check.

This is my theory. So far, many experts agree with me. I don't think turbonetics will agree with us. I'm gonna call technosquare to see if they can help.

 

they are strange codes. I, too, feel that they have nothing to do with the rear O2 sensors. THE FSM states that the code is reltaed to the upstream O2 sensors.

the wierd part is that one code is for being too rich in one bank, while the other code is for being too lean on the other bank.

I have just learned to live with them.....along with the P0300 misfire code.

These are my dashboard friends.

 

Agony? It sounds like you have barely even tried to troubleshoot it yourself. If it can't be replicated at Turbonetics, unfortunately can't spoon feed you a fix from 2000 miles away.

Anyway, here's my reply to your exact same post in the other thread:

 

Taurran, you are overlooking the obvious here. This is only an issue on 2004.5 + cars. T'netics is not seeing it because they are not using 2004.5 + cars. Spoon feed...whatever you condescending narrow visioned person. You have no idea how much I've helped Turbonetics in the past.

 

Do we know this as absolute fact? Has every single 04.5 car that has this kit installed thrown the same codes? From what I've seen and heard, I think the answer would be no.

I'm making the assumption that if they have been all along, there would have been a much larger issue on our hands. It seems that it is a certain "few" 04.5+ cars that have experienced it.

I think you're underestimating what's involved in reflashing a new custom tune with the system they have licensed. Ed is stating that they cannot simply and quickly make you new maps and send them out.

What someone needs to try is troubleshooting one of these "problem" cars and providing some real info as to the root and fix to the problem (although other cars have been fixed in more traditional manner). Someone with the problem is going to have to try these things.


Edit: Nice ninja edit on that one. My vision is not narrow - I'm being "realistic" and you are not. Your expectations of what can be done to help your special situation are FAR from realistic. Provide some real data and maybe they CAN help you.

 

Ed's statement from the other thread. He's already told you they cannot simply custom tune your car with their reflash software. How much more plain does he need to be?

Throw them a bone here and be a little proactive and understanding of what really needs to be done. No, this is not something they can "spoon feed" anyone a fix for, besides the ones' that they've suggested and have worked in the past which are quick and easy.

 

Taurran, I appreciate your help. I know your intentions are good. Thank you for the input.

I've been tuning on many different ecu platforms for over 6 years. I completely know what's involved with VQ flash tuning. It's very indirect and time consuming. It's not a perfect way of doing things, but keeps the factory ecu in place directing all control.

The problem with the 04.5 + cars is more present than most would ever know. I know the problem is in the map. The "canned" map has to be very forgiving since it goes in all cars across teh country. Not everyone can get 93 octane from the pump, therefore the standard issue flash mapping is conservative (overly rich).

What the problem here is the fact that the T'netics ad for the ST states "No Additional Tuning Necessary". It's not my car, but it's def my problem. The owner doesn't want to pay any additional money because of what the ad states.

I totally understand, beyond most on the forum, that once you go FI there are certain "drawbacks" involved. 50 year old professionals do not. Well educated analytical thinkers (not including myself) can see it as false advertisement.

I don't personally sweat the "check engine" light. I understand all the systems and why they can't always work together. What I need is for Turbonetics to step up and satisfy an irate customer. It wouldn't even hurt for them to foot the bill for a custom flash to "fix" the issue. They could consider it R&D.

 

That's fine, but as an analytical thinker I know that there are costs involved in R&D, and that there are certain problems that cannot be fixed in a cost effective manner from 2000+ miles away.

That being said, it's really their call. I am obviously not in a position to tell either party what is going to happen.

Your estimation as to the source of it sounds logical to me, but it still does not fully explain to me why it's not a constant on these cars. You stated that he's running in high 11's in the top of the RPM band, but if it were a fuel pressure issue due to the fuel bucket mod then he would be rich across the rpm range. It sounds even slightly leaner than I'm used to seeing.

I'm actually interested in seeing if a UTEC tune could tune this out. I can't recall off hand what throttle position the stock ECU will switch over to open map fueling but I believe the utec cuts in at 60%.

 

Do you have any AFR graphs from this car running on the dyno?

 

Interested in your plan of attack since I've already dumped too much $$ into this situation.. the past 2 years

 

Have you installed any other sort of engine management?

 

Utec with MAP sensor. Didn't help.