Assistance Needed!!!

I have a 2004 350z, with a newly installed HKS Supercharger. I am running 600cc DW injectors.

The ECU is a Greddy E-manage Ultimate using the stock MAF sensor and an additional Greddy MAP sensor.

My car is with my tuner, it's been there for 4 days now.

The issue my tuner is having is that it will not rev past 5000rpm. When it gets to 5000rpms it will feel like it's hitting the rev limiter/fuel cut.

We have checked the boost limit cut setting voltage and it is at 5volts.

Does anyone have any clues? ideas? or experience in this?

It's making 335HP up until 5000rpms, so it doesn't seem like it's in limp mode.

PLEASE HELP I really need your assistance!

Regards,

Ian

 

are you tuning off the MAF or MAP sensor?

 

They are tuning off the MAF, the Greddy emanage ultimate cannot tune without the stock MAF.

My theory is that the MAF is maxing out which is where the MAP needs to come in?

Thoughts?

 

Your maf is hitting 5 volts (max) around 5000 rpm and the emanage/ecu is likely saving you from pending doom. get real engine management please.

 

Thanks djamps.

We have the volts clamped @ 4.9 volts, so it should not be hitting over 5 volts.

Lots of people have3 had success with the emanage, its no Haltech, but it does an adequate job.

 

^^ probably just going to make it cut out at a lower rpm now. Seems like you're stuck in closed loop. Be careful.

 

You are quite right. they tried lowering to 4volts to test, however this caused it to cut out sooner like you suggested.

You seem to know quite a bit about this, do you have a suggestion apart from getting a full standalone ECU?

 

 

You need to tune using MAP instead of Fuel.




http://g35driver.com/forums/2488257-post10.html

 

i love it, JT comes thru even after his demise LOL

 

Hmm Ink if you have the boost sensor from Greddy with harness sounds like a setup issue. You have to clamp your voltage (usually 4.9 or so) and set your fuel map to external greddy pressure sensor from menu. It sounds like you're ONLY using the MAF sensor. Not to insult you or your installer but you did cut the MAF wire right with in and out per the Greddy instructions? Once you do that, stock ECU will work off the MAF but your additional injector map (you do have the additional INJ harness tapped into inj wires right?) will add fuel to the specified degree and everything will work pretty well. Done it many times before with excellent results.

 

Thanks Guys!!!!!

Problem solved!!!

A "dummy" map was made for the stock MAF, while they tuned off the Greddy MAP!!!

Also, thanks for that info athenG!!! That was awesome and was exactly what they did!

 

Damn wish I would have seen this sooner, I could have thrown a few ideas since iv been tuning emanage blue and ultimate for 3years or so. Its always best to tune using MAP(greddy pressure sensor for example, i have also used a GM map sensor, *psi).

You are tuning with MAF adjustment? or do you also have the injector harness hooked up? Remember that when you have alot of MAF adjustment you are indirectly changing your timing (take away fuel = more timing)

 

Not sure, will need to confirm with tuner.

Once i get it back from the tuner, i can log the maps and send to you to double check if you don't mind Streetzlegend?

I'm pretty sure they were tuning off the MAP.

 

I can take a look.

So you dont know if they are tuning by adjusting MAF signal or by Injectors? How much boost will you be running?

 

They're tuning via MAP sensor, which means they tuning over PSI, not the MAF.

 

Not sure you understand. You have two ways of adjusting your fuel, you have the airflow correction table, and you have the injector table. Each table you can have PSI x RPM. Which means, say your tuning using the MAF signal, you set it to read PSI and RPM, and you make MAF corrections given certain conditions such as 10psi at 4000rpm you put -10 (to remove fuel), that -10 is decreasing the voltages of the MAF signal going into the ECU, therefore the ECU removes fuel thinking there is less air than what the maf is actually reading, the problem with that, is that the ECU also changes timing, which can be dangerous depending how much fuel your subtracting and how much boost your at.

The better way of tuning is via the injectors, the same thing you have PSI X RPM on the table, and you can adjust duty cycle, or duration, so given the conditions, 7psi at 3400rpm you add or remove fuel, it gets the signal coming from the ECU injector wires and alters it to add or remove, then sends the signal to the injectors.

In other words, Tuning with MAP just means that your reading pressure, you still gotta see what is being used to adjust fuel, Maf signal or injectors.
This is just to tell you more or less how it works

 

^^ Thanks for that, I have a better understanding of it now.

You mentioned earlier about an injector harness to tune via injectors. I don't believe I have this unless it comes with the Greddy ecu harness that plugs into our factory ecu? Which means they are tuning via maf?

 

I will always recommend go UTEC or full standalone.

At least with the UTEC you've got real timing control (tuning from TDC), knock and overboost cut.

Any other 'piggyback' is just delays disaster in my opinion.

Good luck!

 

You could also use Uprev (type of reflash) but there are only two or three tuners in the world I would trust with FI on Uprev -- when it's done just right it's heaven... done wrong it's hell for you and your engine.