Engine Light; Code P0402

[Khaosie]

I keep getting this code cause my MIL to pop up, but only under certain condition

I can redline the car through the gears and it won't come on. I can floor it it any gear except third and it won't come on.

As soon as I hold it in third and pass, say 4-4.5k revs, it'll come on. Keep it below 4k RPM and it won't come on.

I've got an OBD scanner/tool/thing, so I just keep wiping it. I've repeatedly wiped and tried to make it come back on, only to test under what conditions it comes back on, which is as described. I can keep it off by driving normally.

It's had a new EGR in the past few months, as the light would come stay on regardless with the same code, so a mechanic friend recommended a replacement. Sorted it, until I passed 4-4.5k RPM in third.

Engine is BBY, no mods.

Any help would be appreciated.

Cheers.

Edit: P0420 popped up today. Had rear cat and O2 sensor changed in February. This car hates me.

 

[RUM4MO]

BBY engine, hum, did you perform basic functions on the new EGR valve when it was fitted? Also, has anyone checked the port on the throttle body or the adaptor below that where the EGR valve pipe connects to as that gets blocked.

Edit:- One other question, does that engine use quite a lot of oil?

 

[Khaosie]

I wouldn't know about the basic functions as I didn't personally replace it, it was having the timing belt done at the time and I got the garage to fit the EGR whilst the car was there.

The port where the EGR tube fits to the throttle body was fairly dirty, but not obstructed. I cleaned it recently as I thought it would help.

It does, I used to top it up about 1l every two months before I serviced it, but I'm a delivery driver so I cover a lot of mileage, so I didn't think too much of it.

Also, there is a minor leak coming from somewhere on the back of the engine, the sump has been replaced as that had a hole too, so this stopped that. But this oil runs down the sump and collects on the sump bolt. It barely leaves a mark when parked up overnight. I read something about an "Oil/Air separator" (I think) getting blocked and simplest thing to do is to replace it. Is this what you're suspecting...?

 

[RUM4MO]

Oh well, at least you have made sure that the EGR gasses port is not chocked, I had that, it seems that that can cause , excessive or low flow warnings (?!). The air/oil separator, I replaced that as the car was using oil, and it did sort that out, as to what was wrong with the original separator I've yet to find out. These things are not made of opening though I have nothing to lose as the old one is still in my garage. The separator does cost a bit though, probably £80+ as it has a flap motor in it. One other issue I had with that car was that suffered from pinking, that I think, was down to burning oil, though I continue to feed it with VPower Nitro to shut it up and that gives it a bit more drivability.

Minor leak at the rear of the engine could well be the EGR valve seals leaking. There are two of them and I think that the big one was replaced by a better one, daughter's late 2009 Ibiza with a later version of that engine, had a leak round about there, I bought new seals but have not fitted them yet, I did not think that the early engines had this problem with leaking EGR valve seals - ie had never read anything about that, though the much later ones did have this issue.