EGR excessive flow conundrum

[professorfate]

Hi folks. Yet another egr post but this one's got me stumped. BBZ engine with EGR Excessive Flow code on my OBD reader, no biggie as have cleaned valve previously but this time has not worked so cleaned throttle body (kept it connected to wiring loom) and the transfer pipe which wasn't blocked.WD40'd all the connectors. Went for a decent run afterwards (engine running fine) but Dash Light still on... any ideas  

[felicia16v]

valve stuck open or an air leak on the servo pipe possibly.

[professorfate]

OOps, forgot to mention that valve doesn't seem to be stuck open - the liquid cleaner didn't flow between the ports. Will recheck the servo pipe for a leak...

[sepulchrave]

Look at the EVAP purge vacuum circuit as well, you need to check that all the vacuum pipes connected to the manifold are not leaking at all, the ECU only has the MAP sensor to tell it if there is gas entering the manifold when the throttle is shut, so any leak would be interpreted by the ECU as the EGR valve not closing properly, hence the excessive flow code.

 

The EVAP valve itself will only trigger a code if it goes open circuit since it's a simple open or shut solenoid with a mechanical spring holding it shut. Failing that you may have a manifold leak although it's unlikely unless it's been removed at some point and not re-fitted correctly.

[professorfate]

Sorry to bump this thread but nothing found so far to solve the problem. As need to adapt a new egr valve got a quote from local main dealer to fit new one and would be in region of £400(parts/labour and clean inlet manifold which didnt seem very coked up when i cleaned the throttle) ! Can a new valve be fitted without adapting?

[sepulchrave]

Sorry to bump this thread but nothing found so far to solve the problem. As need to adapt a new egr valve got a quote from local main dealer to fit new one and would be in region of £400(parts/labour and clean inlet manifold which didnt seem very coked up when i cleaned the throttle) ! Can a new valve be fitted without adapting?

 

Yes, you'll just have to put up with the CEL being on all the time.