First post: Trouble getting the tune right.

Wilson101 · Post by **Wilson101** » Mon Dec 03, 2007 6:36 am

My setup is 9:1 compression, 480cc injectors but im troubleshooting with stock 260cc, z32 afm,hx35 turbo and 87t ecu .

Here what ive done so far. ADR: i set the "afm leg offset" to 0 since im using a z32 afm.

i loaded the 87t bin and changed the afm from z31 to the z32 this changes my injector mutipler from 607 to 1597 i load and burn it to the ecu.

Turn the ignition on i look at the consult display:
afm: 1.820+/-
temp: 158 after running
batt: 5.6 My battery is really at 12.3 volts this figure doesnt change even if the car is on.
ftemp: 213

I turn the car on and it idles really rough only when i lower the injector mutipler down to 800-900 i can make it idle steady as a rock. But when i give it some throttle it bogs down and blows black smoke.

I read the battery voltage is important and affect the fuel map? And that there is a new firmware the fixes this?

Ive been playing around with it for 2 days and cant figure it out.

Thanks for reading

Matt · Post by **Matt** » Mon Dec 03, 2007 8:55 am

There is currently an issue outstanding with the AFM adjustment on Z31

10491 AFM K constant adjustment Z31/R31 AFMs only affected. Seems that perhaps 2-7 to 0-5 volt modification may affect this?

What it means is that on these two ecus that the K constant gets thrown way out to what it should be after doing the adjustment. I've still got to work out the correct offset to apply for the voltage to change to get it more splot on

You will need to adjust your K constant using a wideband to a closer value. Bernard has indicated he used
viewtopic.php?t=431

012Fh (303 decimal) for bosch/ford cfi 440cc injectors/z32maf

This is quite a bit less than 607 that you are currently using even though you are using 480CC injectors. Bigger injectors in general need K smaller

Try pulling K value back further and make sure you dont foul up your plugs

Turn off O2 sensor feedback (increase this value to 255) or disconnect your O2 sensor. Otherwise the ECU will try and get running from stoich when it gets feedback and run crap when you gun it.

For example I can make the K constant bad on my R31 and get it eventually learning / running okay using O2 feedback but once I rev it hard, it will splutter and die because K constant isnt right

In regards to the voltage being displayed, this shouldn't affect operation on the vehicle but I can exchange over your board for one with the fixed up battery value. Shoot me an email with postage details and I'll organise a replacement

Wilson101 · Post by **Wilson101** » Wed Dec 05, 2007 9:48 am

I only have the wide band (not connected to nistune).
When i had the car running it was with the stock 260cc injectors and idle was perfect.

Yesterday i installed my 480cc injectors the K value is 865 (moved it up and down) with the z32 afm. I played with the injector latency from 0 to 3000us with no turn over it just sputters every once in a crank. Ive tried a new set of spark plugs and rechecked the compression, all cylinders read 210. Here is my bin if anyone wants to look at it.

Something new i noticed the voltage now reads 12.8 and now my afm reads .380 (bad afm?)

Question: can i reuse my z31 afm successfuly post resistor mod?

Bernardd · Post by **Bernardd** » Wed Dec 05, 2007 10:20 am

Matt wrote: viewtopic.php?t=431
012Fh (303 decimal) for bosch/ford cfi 440cc injectors/z32maf

in case you missed it the first time.

your kvalue will most likely be a bit smaller

Matt · Post by **Matt** » Wed Dec 05, 2007 10:41 am

Your MAF voltage will now read 0 - 5 volts in NIStune once you have
(a) performed the resistor modifications
(b) installed the Z32 MAF and
(c) changed the address file

If you wish to plug the Z31 MAF in just to get your injectors running right again, you will need to reverse all three changes

Anyway try a way lower K constant value, like what bernard highlighted

and see how that goes

Wilson101 · Post by **Wilson101** » Wed Dec 05, 2007 11:47 am

Thz for the reply:roll: I think most here agree that working on cars its love hate relationship.

Wilson101 · Post by **Wilson101** » Sat Dec 08, 2007 10:47 am

I found the problem......................... Apparently Nistune needs gasoline in gas tank to the pump to injectors.

I decided to pull fuel line off to see if there was gas getting to the injectors it only split a few drops, when opened the fuel level sensor and took a look the tank had hardly any gas.
Well i laughed about it all the way to and back from the gas station. Poured some gas, it turn on and drove GREAT, quick as a mofo too.

Thz Matt!!! apparently my problem was the simplest one.

P.S: i feel like a retard.

Matt · Post by **Matt** » Sun Dec 16, 2007 12:21 am

LOL thats the best one I've read so far

crans · Post by **crans** » Sun Dec 23, 2007 12:14 am

Wilson your a brave man i wouldn't have admitted to that