Exhaust Gas?
FYI
The linear EGR used from 94 on is not as likely to recover from a good cleaning as the digital EGR used from 1990 to 1993 is, but it HAS been done.
I agree with getting a gasket and giving it a try.
The linear EGR used from 94 on is not as likely to recover from a good cleaning as the digital EGR used from 1990 to 1993 is, but it HAS been done.
I agree with getting a gasket and giving it a try.
Like Bill said, just clean the pintle valve in the center of the casting with carb cleaner til it moves freely and does not stick. Be sure to hold it in the upright position so as not to let any carb cleaner run into the can. It will eat the varnish off the windings and render it useless $$$.
Ok, cleaned it up and everything. It had a lot of gunk in it and over it. After clearing the code again, the light came back on. Should I just get a whole new piece now, and will that solve the problem? I didnt see any gaskets, unless it was heat welded onto the piece :?
Before replacing the valve, the '95 service manual advises to check the wiring to make sure the EGR valve is getting the correct signals from the PCM to open. The manual gives a procedure for checking the valve operation with a scan tool. I will try to list some things you can check without the tool to verify that the valve is bad.
You should have a 5-pin connector at the valve
E - pink..........to PCM RA15..... EGR ignition filter
A - gy/bk*......to PCM RA16..... EGR control
C - brown........to PCM BF12..... EGR pintle position
D - gy/bk........to PCM WC10..... EGR +5V reference
B - black.........to PCM WC6 ............... Sensor ground
*gray at PCM
The pink wire from terminal E to the PCM is connected with a splice to another pink wire that draws power through the 15 amp cruise control fuse in the relay center that is fed with ignition current. Check that fuse.
Diagnostic aids: An intermittent may be caused by a wire broken inside the insulation. Check for:
Poor connection or damaged harness: Inspect PCM harness connectors for backed out terminal RA16, improper mating, broken locks, improperly formed or damaged terminal, poor terminal to wire connection and damaged harness.
Intermittent test: If connections and harness check OK, monitor a digital voltmeter connected between terminal RA16 and ground while moving related connectors and wiring harness. If a wiring failure is induced, the voltage will change.
If above items are OK, replace the valve.
Other tests include:
Key on, engine off
Disconnect EGR valve electrical connector
Connect a test light between EGR valve harness connector terminal A and E
Test light should be OFF
I'm no electrician, but it appears that terminal E of the wiring harness should have 12V when the ignition is on. It looks like the PCM controls the Valve by supplying ground through RA16. If this is correct, you could test the valve to see if the pintle moves by applying 12V+ to valve teminal E and grounding valve terminal A.
You might want to wait for a smarter person to confirm this. I'd hate to be responsible for you ruining a $100 component. If you have a scan tool (not a code reader) let me know and I can scan the full test procedure for you.
[edit: You could splice into the wires feeding A and E and run them to a voltmeter in the car. Then as you drive, you could watch the voltmeter to see if the PCM provides voltage to open the valve. I'm not sure that test would be definitive, but it is probably safer than hooking up 12V to the valve directly. ]
You should have a 5-pin connector at the valve
E - pink..........to PCM RA15..... EGR ignition filter
A - gy/bk*......to PCM RA16..... EGR control
C - brown........to PCM BF12..... EGR pintle position
D - gy/bk........to PCM WC10..... EGR +5V reference
B - black.........to PCM WC6 ............... Sensor ground
*gray at PCM
The pink wire from terminal E to the PCM is connected with a splice to another pink wire that draws power through the 15 amp cruise control fuse in the relay center that is fed with ignition current. Check that fuse.
Diagnostic aids: An intermittent may be caused by a wire broken inside the insulation. Check for:
Poor connection or damaged harness: Inspect PCM harness connectors for backed out terminal RA16, improper mating, broken locks, improperly formed or damaged terminal, poor terminal to wire connection and damaged harness.
Intermittent test: If connections and harness check OK, monitor a digital voltmeter connected between terminal RA16 and ground while moving related connectors and wiring harness. If a wiring failure is induced, the voltage will change.
If above items are OK, replace the valve.
Other tests include:
Key on, engine off
Disconnect EGR valve electrical connector
Connect a test light between EGR valve harness connector terminal A and E
Test light should be OFF
I'm no electrician, but it appears that terminal E of the wiring harness should have 12V when the ignition is on. It looks like the PCM controls the Valve by supplying ground through RA16. If this is correct, you could test the valve to see if the pintle moves by applying 12V+ to valve teminal E and grounding valve terminal A.
You might want to wait for a smarter person to confirm this. I'd hate to be responsible for you ruining a $100 component. If you have a scan tool (not a code reader) let me know and I can scan the full test procedure for you.
[edit: You could splice into the wires feeding A and E and run them to a voltmeter in the car. Then as you drive, you could watch the voltmeter to see if the PCM provides voltage to open the valve. I'm not sure that test would be definitive, but it is probably safer than hooking up 12V to the valve directly. ]
You know, I think the wires are all ok. At least they looked decent and still had some type of plastic protectant over them.
The new egr piece will be exactly what I took off the car, right?
The new egr piece will be exactly what I took off the car, right?
Yep, linear EGR valve, item 1 in the image below. Should be the same thing you took off. If you are gonna get a new one anyway, and assuming you cannot return it if it turns out not to fix the problem, why not put 12V across A and E on the old one and see if the pintle moves? If it does, maybe the problem is not the valve. Just a thought. I'm so cheap.

FSM shows a gasket, too. Maybe yours was stuck fast to the valve or the base.

FSM shows a gasket, too. Maybe yours was stuck fast to the valve or the base.
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