My check engine light went off, giving me the codes:
0304 (knock sensor) and
1005 (EGR solenoid valve or circuit fault)

I had checked the codes only 2 days earlier and it read 0505 (all clear), so I'm pretty sure the two codes were triggered at about the same time. The engine is running a little rougher, especially at low RPMs, so something is wrong. I checked the knock sensor and everything was fine there, but there is definetly something wrong with the EGR control solenoid valve. I believe it's a wiring problem.

When I have the egnition key in the ON position (engine still off), there should be battery voltage across the two wires going to the solenoid. Instead of having battery voltage across the terminals, I have 2.0 volts. If I check each of the wires against the ground, this is what I recieve:

Red/Yellow +12.2 Volts
Blue/Black +10.2 Volts

My battery was showing a voltage of 12.2 Volts. It would seem that the Blue/Black line is at fault, but looking at some wiring diagrams, I'm not so sure.

Question 1 Does anyone know the correct voltage and polarity that should be displayed across the EGR solenoid when the ignition key is turned to the on position. (Facing the engine bay from the front, the EGR solenoid electrical connector is located to the right of the front cylinder head and in directly in front of the throttle body. It's a green connector. If you slide the black sheath slightly away from the green connector, you should see a red/yellow wire and a blue/black wire.)

Question 2 Would a faultly EGR system trigger the knock sensor? It would make sense since the EGR system affects the temperature of combustion, but I don't know for sure.

Thanks for any help!

 

Anyone? The only thing that I need is the correct polarity of the two wires coming from the wire harness that connects to the EGR solenoid. Ideally, I could just test it myself on a working max, but I am spending the summer in Williston, ND. I haven't seen another maxima since I've been here. If anyone has a multimeter and a minute, I'd greatly appreciate it!

 

I'll paypal anyone 5$ who will do this. It just takes 2 minutes. If my instructions are too vague or incomplete, I will be more than happy to clarify. I know I'm kind of new here (heck, does 13 posts even get me into the "newb" category?), but if someone could help me out, I would be more than grateful. Thanks!

 

To check operation of this EGR control solenoid, dissconnect the electrical connector and connect a ground wire to one of its terminals and a fuesed battery voltage to the other terminal.
It should be possible to blow air through the two vaccum ports that are adjucent to one another when there is battery power applied, but impossible to do so when it is not energized with battery voltage.
That is out of hte Haynes manual.



Fix EGR before doing KS.

 

It also says :
Disconnect the solenoid vavle harness connector and check for battery voltage between terminals with the ignition key ON. Battery voltage should be present. If battery voltage is not present, check wireing harness.

 

Thanks for the reply! The EGR solenoid does work. I've tested it already. The problem is, as you mentioned in the second post, is that there is not battery voltage between the wires (what I'm trying to do now is to troubleshoot the wiring harness). One of the connectors is not functioning correctly. I don't know which wire is supposed to have the +12V and which wire should be connected to the ground. One of my wires has about +12V and the other has +10V. There is something wrong with the wiring, but to figure out what is wrong, it would be a whole lot easier if I knew the correct polarity of the wiring in a functioning vehicle. That's basically what I'm trying to figure out. Thanks again for the reply!

 

I will check mine tomorrow morning if it is not raining, I can't right now--it's too dark and it is about to rain.

 

Thanks a ton! I have to head back to college in Indiana on Sunday, so I'm trying to get this thing fixed before I head out.

 

I didn't get any voltage from hte blue/black wire.
I got 12+ from the red/yellow one.

 

Post or PM email address and I'll send you the pdf.

 

I check the polarity in my coonector and here's what I got:
Red/Yellow = 12.26 V
Blue/Black + 0.17 V

 

Thanks kevlo911 and GarciaMaxima ! You helped me out a bunch. Hopefully I'll get everything working before the nights up.

DAVE Sz, is that a wiring diagram that you have on a PDF? I have the engine control wiring diagram from the haynes manual, but if you have something better or more detailed, that would be excellent. My email addy is:

broschbj@rose-hulman.edu

BTW, there should be some more detailed info about the EGR system in the stickies. There are at least a couple new threads per day about a clogged EGR system or a solenoid valve error code. Perhaps when I have some free time this semister I could gather as much info as I can regarding EGR problems/solutions and add it to a sticky thread.

 

I just sent it, it's specific to the 1005 code. If it's not enough just say what else you need and I'll try to dig it up.