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Hey forum just wanted some expert opnions on this problem I am having. Have a skyline r33 gts-t mods are in sig. I recently upgraded my ecu to a 300zx ecu chipped and rewired to suit the rb25, now the problem is the car starts but idle it sounds sick its coughing and sputtering and barley kicks over and it can't rev cause when I rev it it doesn't really want to and feels like its bout to cut out. I also noticed the fuel pump doesn't prime as long with the chipped 300zx ecu installed. I just want to kno if it is safe to say the tune on the chip is crap?

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https://www.sau.com.au/forums/topic/239547-advice-needed-with-chipped-ecu/
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first off if you have put a new ECU in you should let it idle for about 15mins i think, correct me if im wrong?

but i rekon its going to be related to the tune that the ECU has already. When they chip ECU the remap the the fuel and air maps to suit the car that it is fitted to.

the car it came off what mods did it have?

Was it chipped for use on rb25 or vg30. As nismoid said sounds like afm to me.

Although if you made the wiring changes then you're probably switched on enough and aware of the need to run a z32 afm with a z32 ecu.

Well as far as I know it was supposed to be chipped for an rb25 and as I stated my mods are in my signature, so you guys should have seen I have a z32 afm already. I didnt get a proper ecu cause the only ecu I want would be a pfc and they are very hard to find and expensive so this was a quick fix until I could get one and I wanted to keep the knock retarding feature of the stock ecu. The car the ecu came off was a stock z32.

Well when it was chipped for the 25 - did they perhaps think of a RB25 AFM?

Have you got another stock ECU to plug in to test with?

That would tell you quite simply/easily if the chipped Z32 ECU is up the clacker

Found this comparison in relation to using a RB PFC in a Z32:

http://www.aus300zx.com/forum/showthread.php?t=271413

The injectors are also wired differently (different pin-outs from the ECU). Might be a contributor to the problem.

I have posted up the wiring changes to use a z32 ecu somewhere here.

Nismoid is still on track I believe and I'd try a std z32 ecu.

Can you get the rom image off the chip and post it up, then we'd really get to the bottom of this.

I believe that this is a viable solution for r33 ecu woes esp.

So don't look at this as a quick fix as I fail to see the benefits of using a PFC now that you have made the wiring changes.

Use Nistune with wideband and I feel that you would have a superior setup anyway.

Let the flaming begin!!!!!!!!

Edit found wiring changes doc.

http://www.skylinesaustralia.com/forums/in...t&id=156978

Edited by Mr Jollwah

With standard z32 ecu car cranks but does not turn over. Nismoid said that they could have thought rb25 afm right? But, seeing as I have an afc neo attached to the ecu with the settings to run a z32 afm wouldn't that overide the rb25 afm signal and send the z32 afm signal to the ecu? When Nismoid said to use a stock ecu he did mean a z32 one right or did he mean a rb25 one?

rb25 one, the one thats made for the car, not some abortion

LOL abortion I like that. But i rewired and put the standard rb25 ecu in an the car started an ran fine. Swhat would your expert analysis be, that the tune on the chipped ecu is bad?

Yea I was using the neo with the z32, but the neo is untuned only change on it was to allow me to run a z32 afm with the the stock rb25 ecu. I got the ecu for about 80 dollars. Hmm do you think that could be the prob that I forgot to change the output of the signal back to a z32?

Yea I was using the neo with the z32, but the neo is untuned only change on it was to allow me to run a z32 afm with the the stock rb25 ecu. I got the ecu for about 80 dollars. Hmm do you think that could be the prob that I forgot to change the output of the signal back to a z32?

Its a possibilty, I mean if the ecu was supposed to use a z32 meter and you have a afc altering the signal then I guess that would cause some grief.

PM if you want sell this ecu later on...

would l be correct in thinking this is one of those 'universal' type mod chips? The ones which are designed just for the sake of it rather than tuned for your vehicle?

Ive heard these things cause more damage than good but correct me if im wrong.

Cheers

Hang on... your running a chipped/modded ECU... AND a AFC???

What on earth for?

Cause I did not disconnect the afc when rewiring and I was thinking I could use it to fine tune the ecu a bit after the install. Yea I guess you can call it a universal chip, but it only works with the rb25, as they didnt put my car on the dyno just used base rb25 maps, advanced ignition, remove speed cut and designed to use z32 afm. Hence why I figured i could use an afc neo to fine tune it.

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