Stll Stalling When Reading KOER Codes

[93SHO_2]

I replaced the Idle Air Control module and still the engine stalls when performing the KOER test.

The KOEO test came back 111, the stored codes are items that have been corrected except for code 718 and 921 which I can't find in my code book.

The reader works fine on my 5 speed.

 

[projectSHO89]

Firsty of all, it is impossible for the code reader to be causing this issue. The problem is in the engine management system.

Try unplugging the vacuum line to the EGR valve then re-running the KOER test.

During the test, the EGR valve is opened and the output of the DPFE sensor is checked to see if engine speed changed. If the computer does not see a drop in RPMs, it continues to open the EGR valve while still looking for that signal from the DPFE. It is possible that the sensor has failed and the EGR valve is opening so far that the engine is stalling. As I recall when testing my old 94 that had a bad DPFE sensor, the KEOR test would bring the engine almost to stalling while running this test. After the sensor was replaced, the EGR system test was not even noticeable.

With the EGR valve unplugged, the possibility of EGR-induced stalling is eliminated. You can then determine if it still stalls, or if the test continues to execute and reach completion. If it does, you are guaranteed to receive an EGR fault code from this diagnostic due to the disconnected vacuum line. OTOH, you may also be able to get other codes that will assist you in the remaining testing to be performed.

Steve

 

[93SHO_2]

Feeling kinda dumb at the moment, I can't find the Differential Pressure Feedback EGR, nor the EGR in my Helms manual. Where are these 2 items, anyone got a photo?

 

[projectSHO89]

The EGR valve is that flying saucer-shaped device bolted to the intake manifold just to the rear of the throttle body. Locate the small plastic/rubber line on it, that's the one I referred to.

The DPFE sensor is the rectangular "box" mounted on the firewall side of the intake. One electrical connector on one side, two rubber lines on the bottom.

Steve