How to get at the EGR return?

**frozenlead** · 07-17-2015

Hey guys,

Have a lovely old 04 GTP with 170k

My car is throwing codes P0303 and P0405. A while back it had a serious rough idle so I cleaned up the throttle body and the EGR valve (they were rather dirty), but I never looked at how much carbon was in the little tube that connects the EGR with the intake. Tomorrow I want to take a looksee...but the intake for the SC seems to hang over the bolts and the exhaust manifold kinda sits right in front of it...is there room to get a wrench in there and undo it without doing some serious dismantling? I don't know how flexible that tube is.

The car doesn't rough idle now, but it's lacking power and chugging hard under medium-heavy throttle. I've already done plugs, wires, coil pack for #3, and put 2 bottles of fuel injector cleaner through it, so the misfire is a mystery so far. I'll check the fuel injector resistance tomorrow I suppose too.

Last quick question, my dad says I could test if the EGR return is blocked by removing the valve and starting the engine; if it stalls or gets rough, it's not plugged, else it is. Is that a safe procedure? Will it damage the engine?

Otherwise great car, right? Gonna miss it in a few years.

**Scottydoggs** · 07-17-2015

check the wires to the egr first, (dont take the tubes off )

look for cracks in the insulation or any bare wire showing, if you see that thats your issue, its not a flow code, it low voltage.

the other code is a misfire in cylinder 3. what you do is take the plug wire off cylinder tree and swap it with the one next to it, fire it up see if the miss moved to the piston next to it.

if it didnt move, swap the spark plug.

if it still dont move it could be a bad coil, or a bad injectore, you can swap then around too, to see if th emis fire moves.

**frozenlead** · 07-19-2015

Well, it turns out my EGR was carbon'd shut, so I fixed that up. And I switched plugs 3 and 5, and the misfire disappeared.

And then I was happily driving it back home when the coolant elbow exploded.

I guess you can't win em all.