2004 Holden Astra Pricing and Specs

This engine has a reputation for failed EGR valves which are part of the emissions control system and live within the rocker cover. Without this valve working properly, the car’s tailpipe emissions can be higher than they should be, as well as causing the oil leak you’ve noted. And any time you have oil hitting a hot exhaust system, there’s the potential for a fire.

In some cases you can simply change the EGR valve, but experience suggests that with some engines, the solution is to replace the entire rocker cover which will incorporate a new EGR valve. The parts can usually be bought online.

When talking about engine oil (as opposed to transmission, brake, power steering, differential, radiator or other types of oils found in cars) for your Holden TS Astra, a 10W-40 rating is best, though 15W-40 is good and 20W-40 is also OK. Make sure to go with a trusted brand.

Go back to where you bought the struts, perhaps take a photo with you showing them the problem, and ask them for their advice. Make sure the struts you bought are the correct ones.