EGR valve issues

[kolosy0]

hey all,

my gf's '99 LX threw a CEL the other day. pulled into an autozone, got it read as 'excessive egr flow'. so i figured the egr valve was getting stuck open. pulled it off, soaked it in carb cleaner overnight, put it back in and all was well. for a week. the son of a b*tch came back and won't go away. i don't want to buy a new valve as that's $150. i checked around online and read this little blurb on msn - 'Occasional problems on this vehicle are failures of the Exhaust Gas Recirculation (EGR) Valve Passages'. i'm thinking this may be it. any idea what passages they're referring to and how i can test it?

[TurfBurn]

I have a used one you can have for 50 if you want it... :)

But on the more helpful front of things... check the coil resistance... that is one way to check it... the manual online has a test procedure as well.. I"ll have to find that and post it for you. Also, when you have the EGR off check the little passages that go into the IM to make sure they are pretty clean and clear.

I have two EGR's I can sell you I believe. One is from a 4,000 mile vehicle and the other is from 26,000 mile vehicle.

I'll see what I can find for test procedures.

Later.

Steve

[kolosy0]

that may be a good option, but i need to know if that's the problem. the valve looked pretty clean and went through the range of motion without issues. i want to see if it could be this other thin frst. if that's not the case, then i'll grab yours.

*edit*

woops - didn't see the rest of your post (blind mofo). i bought a crap-tacular chiltons or some other knockoff, but it had a test for coil resistance along with the numbers. that all came out ok - everything was within spec. i'm thinking it's the passages. fill in a n00b - the IM is...

tia.

[TurfBurn]

IM is intake manifold.. here is from the Mazda manual:
(more coming)

EGR VALVE INSPECTION
A3U011620300W02
Resistance Inspection
Note
• Perform the following test only when directed.
1. Disconnect the negative battery cable.
2. Inspect resistance of the EGR valve coils.
• If not as specified, replace the EGR valve.
• If as specified, inspect the vacuum hoses for
improper routing, kinks or leakage, and carry
out the “Circuit Open/Short Inspection” and
repair or replace the parts if necessary.
1 EGR valve connector
2 EGR valve
Z3U0116W007
Terminals Resistance (ohm)
C—E
C—A
D—B
D—F
20—24

[TurfBurn]

More:

4. Inspect for an open or short circuit in the following
wiring harnesses by probing the applicable
sensor and SST (104 Pin Breakout Box) terminals
with ohmmeter leads.
Open circuit
• Control circuit (EGR valve connector terminal
E and PCM connector terminal 68)
• Control circuit (EGR valve connector terminal
A and PCM connector terminal 72)
• Control circuit (EGR valve connector terminal
B and PCM connector terminal 46)
• Control circuit (EGR valve connector terminal
F and PCM connector terminal 56)
• Power circuit (EGR valve connector terminal
C or D and main relay connector terminal D through common connector)
Short circuit
• Control circuit (EGR valve connector terminal E and PCM connector terminal 68 to GND)
• Control circuit (EGR valve connector terminal A and PCM connector terminal 72 to GND)
• Control circuit (EGR valve connector terminal B and PCM connector terminal 46 to GND)
• Control circuit (EGR valve connector terminal F and PCM connector terminal 56 to GND)
• Power circuit (EGR valve connector terminal C or D and main relay connector terminal D through common
connector to GND)
5. Remove the EGR valve, and inspect for any damage or clogging. Replace the EGR valve if not as specified.
6. Connect the negative battery cable.
End Of Sie
Y3U116WAK
X3U116WB5
EMISSION SYSTEM
01–16–17
01–16
EGR BOOST SENSOR SOLENOID VALVE INSPECTION
A3U011618744W01
Airflow Inspection
Note
• Perform the following test only when directed.
1. Disconnect the negative battery cable.
2. Remove the EGR boost sensor solenoid valve.
3. Inspect airflow between each port under the
following conditions.
• If not as specified, replace the EGR boost
sensor solenoid valve.
• If as specified, inspect the vacuum hoses for
improper routing, kinks or leakage, and carry
out the “Circuit Open/Short Inspection” and
repair or replace the parts if necessary.
4. Connect the negative battery cable.
Circuit Open/Short Inspection
1. Remove the PCM.
2. Connect the SST (104 Pin Breakout Box) to the
PCM as shown.
3. Tighten the connector attaching screw.
Tightening torque
7.9—10.7 N·m {80—110 kgf·cm, 69.5—95.4
in·lbf}
4. Inspect for an open or short circuit in the following
wiring harnesses by probing the applicable
sensor and SST (104 Pin Breakout Box) terminals
with ohmmeter leads.
Open circuit
• Power circuit (EGR boost sensor solenoid
valve connector terminal A and main relay
connector terminal D through common
connector)
• Control circuit (EGR boost sensor solenoid
valve connector terminal B and PCM
connector terminal 98)
Short circuit
• Power circuit (EGR boost sensor solenoid
valve connector terminal A and main relay connector terminal D through common connector to GND)
• Control circuit (EGR boost sensor solenoid valve connector terminal B and PCM connector terminal 98 to
GND)
5. Install the EGR boost sensor solenoid valve.
6. Connect the negative battery cable.

[kolosy0]

thanks! i'll take a look at these this weekend...

[TurfBurn]

I'll try to get you diagrams yet today... gotta run... but let me know if you end up needing a valve.

Later!

Steve

[Khoga]

omg
i had the same problem
if you would look back a week or 2 ago at the post "EGR Valve"
i had the same issue, went 2 autozone just like kolosy0 there
thanks 4 helpin me out then
and kolosy, thanks for bringing up the topic again

[kolosy0]

so i finally went to the stealership, they're telling me that there are two codes being thrown. one for excessive egr flow, another saying that it's running rich. now they told be that there is a TSB out for the maf/mas or something of that nature and they will fix whatever is causing that. as for hte egr, they're saying that they need to take apart the entire intake tract and clean it by hand and are charging me $400 to do it.

what i'm thinking is that if whatever this TSB addresses made the car run rich, that should account for the extra deposits in the intake tract, and they should eat the cost on the cleaning as well. any way to back this up?

[TurfBurn]

that'd be a hard one as the EGR's ALWAYS get buildup in them... also, ther eis no way to prove that it was the richness that caused it. 400 bucks is WAY high though either way. You can do this cleaning yourself in a couple hours. The one thing they may be doing is actually removing the intake manifold so they can clean it right there too and not get too much carbon in the motor... I can take pictures of the EGR tracts if you like I have the mani sitting in my living room :)

(One tract goes into the opening near where the TB is mounted up and the other tract goes through a small passage and to the EGR tube that goes around the motor to the exhaust manifold. Both of those pass through the EGR solenoid. This can be cleaned with a cheap gun cleaning kit brass brush).

[kolosy0]

that'd be great, thanks. if anything, i'll have it for future reference. i believe they are taking the manifold off, or at least told me they would be, plus they're doing an oil change.

[Khoga]

will cleaning out an electric egr valve make a diffrence or will it need 2 be replaced?