Hi all, took a short drive yesterday, 20 minutes, check engine came on, OBD shows P0400 and P1000, at idle. Revs are ~750 at idle. Recently had some hoses replaced on the cooling system, not sure if it's related. Anyway, before I start worrying about combustion temps, if I'm tooling around town for a few days before I can get to my mechanic this shouldn't be a major problem, right?

 

P1000 means a code has been set and will go away once the P0400 (EGR fault) is corrected. Freeze frame data would be helpful. The EGR monitor activates under deceleration when driveability isn't affected. The ECM commands the EGR full on and the MAP sensor looks for a pressure pulse in the intake tract. If a pulse is sensed then the EGR monitor sets good. No pulse generates a P0400 and P1000 and the monitor won't set.

In my case the freeze frame data indicated incorrect output from the MAP sensor. I fixed that and no further problems. The actual problem wasn't the EGR at all.

 

I drove around with the p0400 for a few months. I managed to somehow damage the egr when I replaced the valley hose. Got a new egr valve from partsgeek all is well now. Manifold leaks have been reported to throw egr code but is a rare occurrence. You may want to go ahead and replace the egr exhaust tube as well as they easily corrode or break.