2008 Fiat Scudo Overboost error code
Discussion
Yeah its pulling vacuum all the time. I've tested the solenoid by putting the gauge on it and putting power through it and it switches on and off ( the old one does as well but it sticks sometimes hence me buying a new one)
I've finally got the software installed so tonight i'll make a start on checking the ECU to see what its doing (or not doing)
i've also got a couple of fuses out, one for the power steering (easy enough) and the fuse for the relays that switch the aux cooling fans on and off (they also cool the intercooler) so maybe having an influence on it (prob not but I'll clutch any straw at the moment)
also thank you for all your help so far
I've finally got the software installed so tonight i'll make a start on checking the ECU to see what its doing (or not doing)
i've also got a couple of fuses out, one for the power steering (easy enough) and the fuse for the relays that switch the aux cooling fans on and off (they also cool the intercooler) so maybe having an influence on it (prob not but I'll clutch any straw at the moment)
also thank you for all your help so far
If the solenoid is working, and the vac pump is working, then there cannot be vac at the actuator when no power is applied to the solenoid.
Because that is a clear indication the solenoid is not working correctly. Either that or someone has put the pipes onto it incorrectly or something.
Because that is a clear indication the solenoid is not working correctly. Either that or someone has put the pipes onto it incorrectly or something.
I get what your saying but both solenoids open to allow vacuum ( or blowing when I'm testing on the workbench) when I put power through them and close off when I remove power, I can feel and hear them opening and closing.
It would appear that the ECU is switching power on but not off ? If that's a possibility, I'll know for sure once I get the diagnostic on
It would appear that the ECU is switching power on but not off ? If that's a possibility, I'll know for sure once I get the diagnostic on
ah to make it clearer, when the solenoid is on the car and wired up (all pipes in the right places) as soon as I start the engine my gauge shows vacuum (almost 1bar, same as outputting from the pump), using a test meter I can see voltage on the supply lead to the solenoid, hence it being "open" making me suspect the ECU at the moment. just adding this as Im not sure I made it clear (my head is fried from working and then trying to sort this out)
And with a meter across the two terminals of the solenoid, does this voltage change when driving ?
Although change is poor wording....with a digital meter, duty cycle would be a better thing to be testing as voltage per say will not change, just that it will be switched off/on rapidly, and perhaps fully off at some point.
This should correlate with requested duty at the ecu.
Although change is poor wording....with a digital meter, duty cycle would be a better thing to be testing as voltage per say will not change, just that it will be switched off/on rapidly, and perhaps fully off at some point.
This should correlate with requested duty at the ecu.
cheers Steve, im in work at the moment but as soon as I get home I'll try that./
The diagnostic software has done an actuator test (i run it quickly late last night) and all solenoids and actuators are working when the ecu is instructed to open/close them. I only had a brief look at various things, i took this screen shot of the air intake information page, don't know if its of any help? I'll be checking it all properly this afternoon.
according to my manual the turbo pressure ref value of 1bar is correct (but at 4000rpm) so the turbo pressure at 750rpm of 1 bar is too high maybe?
sorry if I'm being dull
The diagnostic software has done an actuator test (i run it quickly late last night) and all solenoids and actuators are working when the ecu is instructed to open/close them. I only had a brief look at various things, i took this screen shot of the air intake information page, don't know if its of any help? I'll be checking it all properly this afternoon.
according to my manual the turbo pressure ref value of 1bar is correct (but at 4000rpm) so the turbo pressure at 750rpm of 1 bar is too high maybe?
sorry if I'm being dull
Simply looks like boost and boost target...hopefully boost will follow boost target pretty closely. ( but your problems suggest it probably wont )
But you should also then see if the ecu w/g duty is trying to pull boost back etc by reducing duty ( and then you should see a corresponding change of vac at the actuator itself etc etc
But you should also then see if the ecu w/g duty is trying to pull boost back etc by reducing duty ( and then you should see a corresponding change of vac at the actuator itself etc etc
boost wasn't following target, reading approx 200mbar over at any given point other than idle, so had a proper good search of various image galleries to discover that the third output/input on the solenoid (mine has a blanked off hose on it which has been on there since I bought the van) should have a one way breather on the end ie.
This is to allow the vacuum to bleed off in a timely fashion (the vacuum tester I used was showing it taking quite a while to bleed off when the vacuum was shut off) rather than too slowly (which is causing my overboost problem). As the old actuator was faulty I suspect that's why It never happened with the blocked off hose (actuator leaking the vacuum away)
So after weeks of rebuilding stuff (some necessary some not) it looks like Its all working (a tentative test drive yesterday showed the boost following the target and no errors)
Many many thanks for all your help Stevieturbo and others.
Off to fix the open circuit on the cooling fan now ( some things never end)
This is to allow the vacuum to bleed off in a timely fashion (the vacuum tester I used was showing it taking quite a while to bleed off when the vacuum was shut off) rather than too slowly (which is causing my overboost problem). As the old actuator was faulty I suspect that's why It never happened with the blocked off hose (actuator leaking the vacuum away)
So after weeks of rebuilding stuff (some necessary some not) it looks like Its all working (a tentative test drive yesterday showed the boost following the target and no errors)
Many many thanks for all your help Stevieturbo and others.
Off to fix the open circuit on the cooling fan now ( some things never end)
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