Blowtus

Gday folks. I've just popped an rtek'd n333 in my australian delivered s4 turbo. The car drives 'ok' but is down on power at low rpm, and will jerk around a bit if I open the throttle down low. Feels half like a fuel cut or dodgy tps, but it's not as violent as fuel cut and tps isn't plugged in The afr's appear about the same as before, (according to the narrowband anyway) I don't 'believe' there's an issue there. I suspect the timing is possibly very retarded, partly because things feel fine under high load, but mainly because the old ecu always had 5v feeding into the pressure sensor pin. Could never work out why that was the case, and why the car drove ok. I haven't pulled the values yet, but I assume nothing has changed there.

So basically, does anyone happen to know anything about non U.S ecu's compared to U.S ecu's? I've tried my australian forum previously with little interest, most run aftermarket stuff...

At this point I'm planning on running a wire directly from the pressure sensor (which outputs in the correct range) to the ecu, bypassing whatever bollocks is sending 5v to the pin.

Any thoughts are appreciated

The Spyder

iTrader: (8)

WHY isnt the TPS pluged in??????????????

Blowtus

short answer: I don't like the jerk that shutting the injectors off on closed throttle causes
long answer: see my 'tps removal' post from a while back.

you're right though, I should at least plug the damn thing in for testings sake. Considering the ecu just assumes full throttle, the biggest problems occur down low at full throttle, and the fella who had this ecu before me had the same problems with a tps plugged in, I hold no actual hope for this to achieve anything

Blowtus

not even a murmur eh?

VII

Where did you get this ecu from and how much was it, I wouldn't mind finding a Rtek chipped ecu, I have a N318 and they don't chip those. I took your idea and ditched the S4 TPS aswell.

Blowtus

just a private seller here in aus who shipped it over and could't get it to work right...

HAILERS

****At this point I'm planning on running a wire directly from the pressure sensor (which outputs in the correct range) to the ecu, bypassing whatever bollocks is sending 5v to the pin.
*****************************

You mean the brown/white wire at the boost sensor? That's normal. Ref voltage.

Blowtus

no, the weird thing with the old ecu was 5v reference, and 5v signal *all the time*. The car still ran well and fuel cut at 8.5psi still functioned though, so I can only assume the australian electrics are a bit funky somewhere...

HAILERS

Sounds funky to me to. Should have been 4.5 to 5v ref voltage and the output on the brown/red wire to the ECU and boost gauge should have been varying from 1.???vdc at idle to around 3.???? at full boost.

Blowtus

Ok, I've got the tps connected back up (and set properly) and wired the pressure sensor correctly. Things have 'improved' but the engine still runs lean and soft feeling until high boost is achieved. Also has major stutters around 3500rpm with light throttle. Don't have any lean-ness or stutters with the stock aus ecu. The corrected pressure signal makes the car drive a bit better with the aus ecu too, unsurprisingly

Blowtus

Hah! Don't mind me, seems to be fixed. Wish I understood more about electronics / engine management, but it appears that because I only ran a new wire for the ecu, and left the same wire for the boost gauge, I was getting some added 'funkyness', even though the voltage appeared in spec. No idea why the rtek'd n333 is so much more finnicky when it comes to the pressure sensor voltage, but after just cutting the line to the boost gauge it drives like my aus ecu. Now to rig up a boost gauge and increase the giggle factor...