06 Discovery 3 v6 petrol EGR problems

[jrobin60]

Hey all,

I have a great Discovery 3 that has done 220k. However over the last 6 months I have had idling problems, stalling and not starting every time.
Originally I gave the throttle body a good clean, which helped the idling, car continued to stall and have rough starts, so cleaned the intake system through the throttle body, this has improved my problems significantly but still not perfect :(
One day I will have a diesel Land Rover!

Should I replace the EGR valve? is there such thing as a bypass for a petrol EGR valve?

Thank you :)

[Aussie Jeepster]

Just a thought - have you checked/changed the plugs?
I'm looking at changing mine, but am a little daunted by how hard some are to get to - even my indie screwed up his nose when I mentioned it!!!

[Aussie Jeepster]

Um, stupid question - do petrol engines have EGR valves??

[Disco-tastic]

This one does. It doesn't get anywhere near as gunked up as the diesels, and the petrols dont produce the same amount of soot.

To the OP, as stated check the plugs and leads. If the car does lots of short trips it can foul the plugs as the car runs real rich when cold. And 220km and 10+ years is probably a good run for plugs [emoji106]

Stuffing around with the EGR would be my last check.

[jrobin60]

This one does. It doesn't get anywhere near as gunked up as the diesels, and the petrols dont produce the same amount of soot.

To the OP, as stated check the plugs and leads. If the car does lots of short trips it can foul the plugs as the car runs real rich when cold. And 220km and 10+ years is probably a good run for plugs [emoji106]

Stuffing around with the EGR would be my last check.


Thanks, I hadn't thought about plugs and leads, I will have a look at them next week. My KMs are mostly highways, but now I think about it plugs would be overdue.

[jrobin60]

This one does. It doesn't get anywhere near as gunked up as the diesels, and the petrols dont produce the same amount of soot.

To the OP, as stated check the plugs and leads. If the car does lots of short trips it can foul the plugs as the car runs real rich when cold. And 220km and 10+ years is probably a good run for plugs [emoji106]

Stuffing around with the EGR would be my last check.


Just a thought - have you checked/changed the plugs?
I'm looking at changing mine, but am a little daunted by how hard some are to get to - even my indie screwed up his nose when I mentioned it!!!


I have done plugs on a couple of other cars, but looking at the disco, the front 4 will be easy, getting the ones closest to fire wall don't look like fun. I'll give them a go soon and take some pics as I go.
I removed the EGR in about 30 minutes (quicker if i didn't drop the seal haha) cleaned it out and reinstalled next day, seems to be running well for now.

[Aussie Jeepster]

I have done plugs on a couple of other cars, but looking at the disco, the front 4 will be easy, getting the ones closest to fire wall don't look like fun. I'll give them a go soon and take some pics as I go.
I removed the EGR in about 30 minutes (quicker if i didn't drop the seal haha) cleaned it out and reinstalled next day, seems to be running well for now.

Where is the EGR? photo?

[justinc]

Egr and MAP sensor are all in one, front of engine at throttle body. Easy to fit. They DO fail on the V6 4.0, usually with a MAP sensor fault. if The Barometer inside the ECU detects any more than a relatively small differential in readings to the MAF,it sets a DTC. 99.9% of the time it is the MAP sensor, which is part of the EGR valve.....

[Aussie Jeepster]

Egr and MAP sensor are all in one, front of engine at throttle body. Easy to fit. They DO fail on the V6 4.0, usually with a MAP sensor fault. if The Barometer inside the ECU detects any more than a relatively small differential in readings to the MAF,it sets a DTC. 99.9% of the time it is the MAP sensor, which is part of the EGR valve.....
Oh, is that it!
I thought it might be bigger and more complicated for some reason.
Cleaned it a while back and there was nothing to clean!