Outer Limits 4x4 Board

Does blocking off the EGR valve on petrol engines have the same beneficial effect like on diesels?

I understand the EGR is mainly for emissions at the expense of economy/power but no one seems to be blocking off petrol EGRs in the same snumber as the diesels.

Does blocking off petrol EGRs have any benefit?

When they're working, an EGR valve should only open when the engine is warm and there is sufficient manifold vacuum. It shouldn't open at full throttle. That's if it ever opens, and isn't blocked with a concrete-like crud.

I expect that blocking a (working) EGR valve would theoretically improve fuel economy, but it shouldn't make a difference to full-throttle power.

Also watch doing it to late model EFI systems - it will frequently cause an error to be logged and perhaps bring on the MIL.

Definately dont pull the plug on the valve if its a proportional unit - that will generate a fault.

I've read it can cause pinging and worse economy, but I don't know if that's just scaremongering.

I have heard it can cause longer term pregnancies...

baby yet?

early egr systems where crap and tended to cause poor running and poor economy. however later ones actually help with economy.
but because egr heats up air going in it can cause pinging if your running crap fuel or too much advance.

worse thing with egr systems is keeping them working correctly. they can foul up and stick. high inlet or exhaust restriction can cause excessive egr which will cause poor economy.