Corsa 1.0 engine probs

elektra-2007

My friend has got a problem with his 1l Vreg 1999 corsa. Have put it onto a Modus and it comes up with the code P0505, Looked on Auto Data and it says IDLE CONTROL VALVE BLOCKED, we have changed the idle control valve no change, took off the valve looked inside the throttle body no blockage, swapped the MAF from another Corsa - no change, taken off the ERG valve cleaned it- no change, On Auto Data it gives a list of possible causes and how to test, So today we tested the ERG Valve the restistance was fine as was the voltage, checked the same on The Maf sensor-fine, checked the Idle control sensor fine.
The Sparks are black which suggests the car is running rich, It sounds like a choking dog when it is trying to idle, As you can hear the idle throttle constantly reving to keep the engine going.
Put the Modus back on and the same fault code, looked at signals to the ECU, and it says there is lots more air going in than should be and it says the car is running MEAN but it dosent smell like it and the plugs are black, there was a signal from the idle control and MAF, and EGR. Dont really want to get a new EGR valve at £160 if its not that.
Has anyone any ideas what we could try next or had this problem?

elektra-2007

An Update if anyone out there can help?
Changed the Lamba sensor today which made it a little better but its still hunting and popping....

somech

might be worth taking a look at the coolant temp sensor stick it on modus and check the live data for dodgy readings it may be fooling the ecu into thinking the engines stone cold constantly

sp00nz73

just a point but have you cleared all error codes in the memory and then run the car?

elektra-2007

Hi we had it on the modus yesterday,and the coolant temp was normal I think it got to 87, when we were trying other stuff out.
Its definatly opening the injectors for fuel and loads of air but then struggling to idle, eventually the engine just cuts out as if its flooded or somthing, its a complete mystery, we think there maybe 2 faults but its begining to look imposssible!!!
Any other ideas would be fantastic!
Evertime we try somthing new we clear the codes and start again, but the same code p0505 keeps coming up, we have chsnged the throttle body from another car so we know it isnt blocked.

spaceman5

i had this problem with a fairly old vauxhall vctra, every time we went into idle it would just cut out, sometimes did it when we slowed down to go through corners etc, how i never got hit up the backside i will never know, anyway this never had a computer on, but problem was diagnosed to the wiring, the heat from the engine had melted the insulation around the wiring and the wiring was shorting, causing the engine to cut out at low revs, not saying this is your problem, but being a vauxhall there may be a common problem

mikey72

0505 can be icv voltage low.
Have you checked the voltage on the valve when on idle, and checked the wiring and plug?

elektra-2007

Weve done so much i think were going in circles! On monday I will check the voltage again on the ICT, im sure we did, we also swapped it for a new one and it didnt change so we sent it back, il check the resistance in the wiring harness tho.
As for the wiring shorting, its somthing we have been thinking for a while, we will have to trace the wiring back and check (sigh!)
Thanks for your help, if you have any other ideas i would love to hear them!