Engine light on

I would try to disconnecting the negative 12 V wire and leave it for half hour to reset the computer. I have done it with other issues i had succes with. Jeg ville prøve at se om det ville hjælpe

Christian

 

check the erg valve.

 

Please specify your km's, that will help.

Christian in particular has drawn attention to problems of clogging with the Exhaust Gas Recirculation circuit. It seems a common complaint: build-up of tarry gunk in the EGR and it's connecting pipes. It can spill over into the Intake Manifold too I think.

From the Repair Manual:



I've removed the front pipe, checked for clogging, and cleaned with some carb cleaner. Haven't looked at the rear pipe. That was around 40000 km.

Couple of pics from the Manual. Front view:




Rear:



The front pipe is accessible from above, with the hood up. For the rear pipe you'd want to raise the car and take off the engine under guard. I was under there a couple of days back rustproofing the front suspension, and just happened to notice the EGR. It's not the easiest access, a bit of a reach. And the bolts look like they might be more of a fight, being close to the hot exhaust.

 

Agree, now i think it could be a issue of carbon build up in the EGR and Intake manifold that highly could cause this problem. I cleaned my EGR 2 times and the Manifold alot of times. Recently i also focused on the Fuel Injectors and cleaned them since they were messed up by carbon.

Christian

 

I think these guys probably nailed it.
If you are not mechanically inclined a shop repair probably won't be TOO expensive.

P.S. Please don't post with such tiny font. It is REALLY hard to read.

 

how bad was it? I'm approaching 60,000 miles and thinking about more involved maintenance besides the usual fluids and filters.

 

Any form of vacuum leak at the valve cover and the intake would cause the condition that the OP describes.

 

It was about 25% clogged at the face of the pipe flange, but I suspect it's worse right there, due to the transition. There was minor build up along the length of the pipe. I just ran a strip of towel along it's interior, with some shots of carb cleaner. Beyond both ends of the pipe ( EGR and intake manifold) there was also some build up. Again, haven't looked at the pipe on the exhaust side of the EGR.

 

only after 40,000 km? WOW. I better check mine soon.

 

is that from bad gasoline?

 

I'm thinking bad design. do not know, using Chevron regular.

 

my old '04 with 135,000 miles has no issues. i wouldn't bother opening things up.

 

Dug up the pics. I do believe it's worse right at the flange. The image rotations are messed up, sorry.

 

how do we determine if this is normal, or excessive? affecting drivability or not?

 

That didn't seem to be effecting driveability at all, in my case. Definitive is when you get code P0401.

But intuition tells me if you get that pipe clogged (say) 50%, that's got to be impacting it's effectiveness, ie: there's some redundancy in the design, but how much?

And again, I mainly looked at that outlet pipe, there's another pipe upstream, on the other side of the EGR valve and cooling gizmo, connecting to the exhaust pipe. I'm thinking that one's going to be more clog prone.

And downstream, the pipe I checked feeds into the intake manifold. I could see there was build up in there, I mean there's build up at the flanges at both ends of the pipe. So I do not know.

 

seems like a lot for 40,000, i wonder what it would have looked like at 100k.

 

Driving style could be a factor. Just going from (flakey) memory, think I read (in Repair Manual) the EGR is active during coasting. I'm pretty conservative, do a lot of coasting. Seems too, once it starts clogging it's gonna increase logmarithmically: pipe constricts, so less surface area and same amount of exhaust gas going thru, less net area getting same amount of deposits.

 

40K km ~= 24K miles.

This is an issue only for 3G Prius. Classic and 2G do not have an EGR system.