tuning problem

[joefoe]

Ok all you smart guys on here I really need your help now! I just got my maf pro installed a week ago and I booked some dyno time for this weekend to get it tuned. On the dyno we laid down over 20 runs that aside from the first 2 runs where we set the idle and low range the rest of the runns are the same. Problems is right at 3500 rpm it goes way lean. We can tune below 3500rpm easy add and take away fuel but no mater how much fuel we add nothing will change my AFR after 3500 rpm.

I am on stock 440s and stock turbo a 1:1 AFPR and when I was on the street testing I would see over 40psi when I boosted. So my Fuel system should be good. At this point I am thinking that some thing is causing the ECU to freek out at 3500 RPM because the AFM is gone. Has any one had this problem before.

Willam I know your on the mk3 fourms alot more then me maybe you could piont me to some threds over there or something.

Thanks guys.

[zank]

Try talking to Dr. Jones on Supramania/Supraforums he seems to know alot about this set up.

what route did you choose to go with? Speed density? Iv been thinkin of going with that set up. did you get a a wideband hooked up to that? if so what did you go with?

[joefoe]

I got speed density all hooked up and it runs great under 35K and before the dyno I was pussing it to red line but I wont do then now. I dont have a wide band on it.

[Knight202]

hey joel, gimme a ring when ya got that all done, love to see how that device works. pm me if u dont have contact info, thanks bud

[Supra_devil]

are you maxing out the fuel pump? how much boost are you running.

i am 99% sure my tuning issues was due to fuel supply on my car, kept going lean after 4000rpm.

[joefoe]

all are pulls were @ stock boost with just one washer in the wast gate so only about 8psi. Can you still lean out fuel with out not enugh flow even tho you still have 40psi at the rail?

[cheappower82]

Pull some timing and check the AFR's; I'm also positive that you fuel pump is probably maxed out

[BillyM]

fuel pump is maxed out at 8psi on the stock turbo?

I'm guesin' no on a 7m pump, only maybe on a 5m pump...

You mention seeing XXpsi, does that mean you have a fuel pressure gauge? You can visibly see a fuel pump maxing out very easily on a gauge, take a peek and see if it ever drops psi once it starts ramping up as you get into boost.

Try a run starting at 3700rpm, so your boost wont come in until 4000ish, see if the wot not-fullboost 3500+ afr's are still doing the same thing.

Eh... can the 7m go into default-table mode, and ignore sensors if it suspects a fault? Might check for CEL codes...

---BillyM

[joefoe]

I'm with you Billy. I don't think fuel pump is the problem. Yes had a gauge on it before I went to the dyno because I put on a AFPR and set it for 31 psi then went out and boosted to 12 psi. That was dumb but I know it was rising to well over 40psi and never dropped. I've had a bad fuel pump in my car before and it read on the gauge when I boosted psi dropped. It seems weird to me that it is happening right at 3500 rpm every time. They wouldn't push past 14.7 on the dyno so once we hit 3500 we killed it every pull. I'm going to wire up a check engine light tomorow and see if it's throughing any codes. I have a feeling it's going to be a code 26 AFM problem but then what do I do?

[cheappower82]

what engine management? do you have timing control? also, what's your base timing set at?

[oldschool85]

i seriously doubt you will find an answer here cuz no one here has used it yet. Your best bet is to post a thread at supramania.com cuz its a mk3 forums. Contact malloynx or dr. jones as they have pretty much mastered the maft pro.

[zank]

what engine management? do you have timing control? also, what's your base timing set at?

he is using the MAFT Pro, it has timing monitor, but i have yet to hear anything about controlling it. Last I heard was that they were working on it.

[joefoe]

i seriously doubt you will find an answer here cuz no one here has used it yet. Your best bet is to post a thread at supramania.com cuz its a mk3 forums. Contact malloynx or dr. jones as they have pretty much mastered the maft pro.

Well, they were not much of a help pretty much every one says fuel pump even tho I had a gauge on the rail. As it turns out I had the fuel cut turned up to high and that limits the frequency from the AFM to the ECU. So once it adds up to that frequency limit, that is all the fuel you can get.

[Knight202]

So are you able to turn down the fuel cut and be able to now tune the full RPM range?

[elhsupra]

You got a datalog file? What are your settings? What Map sensor are you using (GM 2 bar, 3 bar, etc)? You say it goes lean, what was the A/F over 3500? What was it below 3500? What are your settings (Low, mid, Hi tune)? What is your base Fuel pressure set to? Probably a stupid question, but have you checked your fuel filter? Another stupid question, is your Airflow source set right, F-Out, F-In? Dr jonez on Supramania/mkIIItech and Turbobob over at Full Throttle Speed Tech forum (http://www.fullthrottletech.com/index.php) are the experts and could probably help more.

[joefoe]

^^^^ Thanks man! But I think you kinda miss read my last post. I've got it working now. You see all it was, was I had the F-out max set to try and raise fuel cut. BUT to raise fuel cut you tell the AFM that it can only send out XXXhtz so the ECU wont trigger F/C. If the AFM only send out XXXhtz once you get to that number you get no more signal to the ECU thus that is the MAX fuel the ECU will send out. I was dissapointed in the advice I was given to track down this problem because to me any one with a good undersatnding of the MAF PRO should have said this right off the bat. Insted I was told it's your fuel system.

[BillyM]

...so once its turned off, are you still hittiing fuel cut?

--Billym

[joefoe]

No not in speed density because even with 440's you still have to lean them out quite a bit to hit good AFR's. I've taken about 20% out through the whole range. Now my F/C is proly pretty high but I think I could now use the F-out max to bring it back down.

I have got to say this is one hella system! I've got it self tuning at WOT to 11.5, it then will give a read out on the sensor screen saying how much fuel it is pulling or adding to your user tune. I can then go make some quick changes to my tune and have it hold 11.5 with out a wide band. After a bunch of hard pulls I noticed some ping, so I checked my air temps it was getting hot so I went and had it add more fuel once it got to the higher temps! I've never tuned before and a side from this one little hick-up this thing has been a snap to use!

[SupraFiend]

now if only it could defeat the stock red line fuel cut.

[BillyM]

Good to hear man... Just remember, the more fuel you pull that way, the more timing the stock system introduces. It may become necessary to bring down the total ADV some if you experience ping.

offtopic: Do any of the FCD's work by NOT clamping the KV signal?

--BillyM

[elhsupra]

^^^^ Thanks man! But I think you kinda miss read my last post.
Sorry, I missed that. I didn't even think about the F out max. Glad to hear its running well for you now. Gotta love that A/F Tracking :D
Timing may not be as much of an issue in the near future as the timing monitor function is working and timing control is in development right now. Have you had a chance to play with the boost control yet?

[joefoe]

now if only it could defeat the stock red line fuel cut.

I'm sure they could do this for us if there was an intrest. Timing controle is right around the corner, and that is because we asked for it. Best pat is the soft ware up dates are free.

Billy I'd like to knwo more about this F/C thing too. But with maf pro in speed density it's really not that big of deal because you can change the VF tables. It's not like th SAFC where you are stuck with just the one conversion.

[SupraFiend]

does the maf pro control the injectors directly though, that would be the only way it could defeat the rpm fuel cut.

[joefoe]

does the maf pro control the injectors directly though, that would be the only way it could defeat the rpm fuel cut.

No it does not it is a still only a trasilator. How exactly does the rpm limiter work?

[SupraFiend]

There was a huge thread on it on supraforums, pretty sure the consensus at the end of it was that the ecu just kills the injectors. I think the Greddy Emanage controls them directly so it defeats the fuel cut but I might have it confused with something else.

[aussiepete]

probably a silly question,but doesnt the MAP ecu stop the whole fuel cut dilemma?im about to buy one from what ive read and feedback from a few users there amazing to tune with.

[joefoe]

It will raise fc a bit even on a stock set up. FC is still very much there. You can limit the htz the ecu gets from the afm (afm is not there so the signal is coming from the maft pro) and this will stop the ecu from hitting FC but it also stops the ecu from giving any more fuel. So if you don't have larger injectors and/or afpr you will run lean.

As for the maft pro being amazing to tune with I think the jury is still out on that one. There have been a number of problems with codes, in my opinon a company shouldn't have a product that even when you install it as per there derections for the car you bought it for it throws ecu codes. They have jimmy'd up some fixes for these issues as the come up but it just shows there R&D is poor. Also the tuner pro soft ware that comes with the maft pro is just plain crap! Tuning ecu's is tricky and there will always be poeple that can't do it right and blame the product, but the issues with the soft ware and poor compatibilty with the mk3 ecu is not a good testament for FTS.

[aussiepete]

this is the unit im talking about.

[aussiepete]

this is the unit im talking about.
http://www.performancemotorresearch.co.nz/