P0507 RPM High

caprice · Post by **caprice** » Thu Oct 18, 2007 3:00 pm

My 2000 leganza 2.2L set a 0507 code and it idles at 1250 RPM and a friends 02 nubria 2.0L has the same code, and his idles at 1500. How do I test it out to be sure it is the IAC? We looked for vacuum leaks.

caprice · Post by **caprice** » Tue Nov 13, 2007 3:08 am

I replaced the IAC, no difference. Adjusted the throttle minimum screw, and adjusted the TPS and I got it to idle 950 for a couple hours (950 is still to high) but then in 24 hours it was back to 1250 rpm and set the code again. it seemed to "learn" the adjustment. What can I do? I am thinking of getting a new TPS, but unsure, since I already replaced the IAC and it didn't fix it. Thats called "throwing parts at it" where in an attempt to fix a vehicle, you replace sensors that aren't the problem, and end up spending money you don't need to. Frustrating! Thanks for any help guys.

MMamdouh · Post by **MMamdouh** » Tue Nov 13, 2007 8:16 am

got vacuum leaks??

MMamdouh

Turtle_Wax · Post by **Turtle_Wax** » Tue Nov 13, 2007 11:02 am

If all connections and vacuum pipes are ok try this. It works for the Lanos.

Turn on ignition and disconnect the Idle speed control valve plug
Ignition off, re-connect the ISCV
Repeat the above 4 or 5 times

Start engine. It may not idle unassisted so use the throttle for a few minutes until the ecu learning phase kicks in.
Should idle normal.

caprice · Post by **caprice** » Wed Nov 14, 2007 5:11 pm

I tried that and it worked, but kind of like replacing the IAC, RPM at 950-1000, and varying a little. The slight moving of the RPMs made me think of the EGR valve. Short story: The EGR gasket leaks, and there is either a crack, a hole, or another leaking gasket on the bottom of the part the EGR mounts to. (Can't see it--need a mirror.) It also holds the temperature sensors. Turns out I could hear the vacuum leak, I couldn't tell it from the engine sound.

Long story; I grabbed a spray bottle of water and sprayed around the gasket, and the engine settled down. Cleaned the carbon and dirt off the gasket and tried again. Still leaking. I can see the water bubbles around the gasket. Sprayed the housing below without getting water on the EGR gasket, and I hear bubbles and engine settles down again. I hear a light sound of a vacuum leak which changes when I put my hand under it where I cant see.

Will get a new EGR gasket and remove the part it bolts to, and report back. Maybe someone will benefit from it.

Turtle_Wax · Post by **Turtle_Wax** » Thu Nov 15, 2007 10:19 am

Sounds like a EGR and Inlet manifold leak. Another way to make sure is spray Inlet/carb cleaner around the leaky areas and the engine revs will rise. While you have the egr off to replace that gasket check that the egr valve itself isn't sticking open, that too will cause symptoms of a vacuum leak and uneven idle.

caprice · Post by **caprice** » Fri Nov 16, 2007 7:12 am

Inlet manifold--you mean the aluminum piece that it on the drivers side of the cylinder head? The EGR, Temp sensor, Temp Sender, Coil pack, and a coolant hose mounts to it. Not to be confused with intake manifold.

What should I use as new gaskets? A cut out gasket or high temperature RTV? Or is it too hot because of the exhaust?

They don't seem to sell regular replacement gaskets at Auto Zone or Checker.

By the way the faulty EGR gasket is the OEM tin one. Can gray RTV (650 Degrees) or copper (700 degrees) be substituted?