Need help A.S.A.P.-Overfueling!!!!!!!!!

RO_SUNNY

Active Member
Hi guys/gals.

So... the trouble is like that.
I have 760 cc injectors, Z32 Maf and 3071 turbo with an Nistune Ecu.
When I want to start the car it just drowns my spark plugs into fuel (as badly as ....when I take the plugs out fuel dribbles from them).
......oooook....now I checked:
-fuel pressure regulator--->ok
-fuel pressure--->ok
-fuel lines connected properly --->ok
-the Z32 afm i think is ok
-injectors--->brand new

Other parts like tps and misc worked in perfect order last time the engine was running.

Could this be from the mapping????
Could this be from the injectors????

Please give me some more advice because right now I am stuck!!!!!!
 

RO_SUNNY

Active Member
Changes over the stock engine:
-760 cc injectors
-z32 AFM
-3071r turbo
-3'' full exhaust
-front mount intercooler
......................and that's it
 

RO_SUNNY

Active Member
A friend of mine had a similar problem with an Vauxhall Astra Gte with an 2.0 16v C20XE engine....he had the engine temperature sensor unpluged......and what you konw??? It had the same simpotms as mine has.....

Could this be true???
 

PobodY

Moderators
Staff member
What have you changed (if anything)?
Sorry, I meant; what have you changed since it was last working?

If it's something simple like you changed the MAF, then see what happens when you put the old one back.
If nothing has changed and it's just started misbehaving then it's a bit harder to work it out.

I wouldn't have thought the temperature sensor would make that much difference. - It would give you a high idle because it would never recognise that the engine is warm, but it shouldn't flood the engine.

Fault codes?
 

Trip

New Member
Sorry, I meant; what have you changed since it was last working?

If it's something simple like you changed the MAF, then see what happens when you put the old one back.
If nothing has changed and it's just started misbehaving then it's a bit harder to work it out.

I wouldn't have thought the temperature sensor would make that much difference. - It would give you a high idle because it would never recognise that the engine is warm, but it shouldn't flood the engine.

Fault codes?
If the ECU senses a fault in the temperature sensor, it will default to 80degC and trigger a CEL.
 

watoga

Member
Hi,

Have you made changes to the k-constant in NIStune? Because you've changed your MAF and injectors, the injector pulse width will probably be too long, resulting in a great deal of overfueling. You will need to greatly reduce the base-level fueling. A ball-park way to do this is simply use the NIStune "Change MAF" and "Change injectors" menus. This will roughly adjust the k-constant, then it's a case of using a wideband air/fuel sensor and fine tuning the k-constant value to give around 14.7/1 at idle.

Cheers,
Dave
 

RO_SUNNY

Active Member
No....i never changed anything in the Nistunes software because Fusion Ed made me a running map that will suite my setup.
He has a really god reputation and also I myself can say that I am very pleased with his services and help.
This is why I am thinking that something else might be wrong.

Maybe my z32 i foocked?!?!?!?
Maybe I should take the injectors out and make an flow test?!?!?!

I will try to make an fault code check aswell!!!
So please help out guys with some ideas/tips/tricks.

Thanks.
 

gtirjoey

Member
Have you contacted Ed see what his advice would be?
As you say he's a helpful chap he sent me an ecu with just a map to get me to him and it worked perfect.
 

Trip

New Member
Was it ever running/starting good with the setup you currently have: ECU, injectors, maf, fuel pressure ?
 

RO_SUNNY

Active Member
@ Trip
So.....I tried to start with the base map which was is installed on the Nistune board and it started on the first try...........I tried it again and started....then I installed the running map which Ed Gave me...and from then it never started again.
Worse then this is the fact that I have to change the oil now which is also flooded in fuel.

I've done an fault code check and it gave me the 12 code (AFM circuit fault).......tomorrow I will verify the wires and also if the jumper is put in the correct position on the Nistune board.
Could this be the reason why it's overfuelling so bad on start up????

I will keep you guys updated.

Thank you very much for the input and much appreciated help!!!!!!
 

Fusion Ed

Active Member
Something is not right. Those injector values I gave you to use I have used a million times on loads of other cars with 700cc + z32. Fact is it would start even if the fuel is +- 15-20% i.e. if your injectors were 600-800cc it would still at least run. For it not go try even at all then there is an additional issue playing part here.
 

RO_SUNNY

Active Member
So...just came back from the garage.

I tried starting it with 80% inj. multi (just like you told me Ed) it starts but still over fuels like hell.
It starts by it wont rev, if I am trying to just blip the throttle it stalls...........and also fuel comes out the exhaust.

I made a Log which I will send tomorrow Ed.

Thanks again guys!
 

Fusion Ed

Active Member
hmm can't say im comfortable with this being unable to check the car physically. It should be ok and infact run fine without messing about. Perhaps keep pulling fuel away and see how it goes then but once its running check everything and dont put it under any load. Ideally you need to find a local garage who can look at it if your not sure.
 

watoga

Member
If possible get a wideband so you can monitor the A/F ratios yourself. It'll save you possible engine damage if you start to run lean.

Dave
 

RO_SUNNY

Active Member
I just checked the AFM wiring and it was a disconected cable.
Cable soldered back in his postition and problem solved......and then another diagnosis....and it showed the 55 code which is all clear.
I have a wide band but it goes from 14 to 25 and not staying steady.

Ed I would go to a garage but my R is the only one in my country! Anyway in my country all the mechanics only know how to change oil and filters:))

I will take out the injectors and make a flow test.......is this a good idea???
 
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