I bought some pizza for the tech @ my local dealer & he hooked my '90 Loyale up to the computer - it threw code-34 "EGR Solenoid" .... went to my local parts store, and they don't even have an EGR valve LISTED (but they do have the gasket), and I see only minimal references to them here ... I search 20+ threads ...

 

Is it just me, or am I in for a world-of-hurt at the dealer? ....

 

This assumes the tech (who admitted he'd never worked on such an old one knew what he was doing ... he plugged his reader into an adaptor, and then into a yello DIN plug on the drivers' side by the firewall ..

 

(Gulp ....)

I've been meaning to make a block plate for the EGR valve on my rig with some 1/4" plate scrap metal laying around.

...tech @ my local dealer & he hooked my '90 Loyale up to the computer - it threw code-34 "EGR Solenoid" .... went to my local parts store, and they don't even have an EGR valve LISTED

(Gulp ....)

The code is for the solenoid, not the valve. The solenoid no longer has the proper resistance, probably either open or shorted. Get a replacement solenoid from junkyard, replace with proper value resistor, or try one of the solenoids from another make of car (someone was talking Toyota a week or so ago).

had similar problem with my audi when I had it. 1993 90cs. The egr solenoid controls when the egr valve itself gets vacuum so that it can act upon the diaphram and hence actuate (sp?) the egr valve. What I had experianced on the audi was that I would get a fault code after a long stretch on the freeway and just as soon as I dropped down to 40 the check light would come on. I suggest that you start replacing vacuum lines. They are a cause of many problems that are not easily identified. SO back to my problem with the audi, the vacuum hose from the egr solenoid valve did not seal well at all on the egr valve end and after I replaced that vacuum hose and "manually" worked the egr vale (lots of sucking and blowing on the egr vacuum line, not a proud moment) I did not have any problems. with codes. Lots of other problems with that audi but not codes Yes my spelling is bad and my writting somewhat conveluted, I know. If you need clarification I shall provide.

It's most likely the solenoid, because, as Northwet said, that's what the code is for. Replace it with a 68 ohm resistor. If that gets rid of the light, then it's definitely the solenod. The car will run fine if you leave the resistor in there. A replacement will cost you $60.00 at thepartsbin.com. Their part number is B7079-60044

I need to find the trick for the ecu into thinking it is good... 10 ohm resistor? or two resistors one ohm for open and another for closed, pretending to follow instructions.I can't find answer just yet.... I have completely taken egr out of mine and lovin it! no odors, gained power and fuel, engine cooler.....

It's most likely the solenoid, because, as Northwet said, that's what the code is for. Replace it with a 68 ohm resistor. If that gets rid of the light, then it's definitely the solenod. The car will run fine if you leave the resistor in there. A replacement will cost you $60.00 at thepartsbin.com. Their part number is B7079-60044

 

Wow, I totally can't believe how awesome this Discussoin Board is ...

 

That came-up as the Purge Valve ... that's not the same thing is it? My parts guy says it's not ... hmmm

Wow, I totally can't believe how awesome this Discussoin Board is ...

 

That came-up as the Purge Valve ... that's not the same thing is it? My parts guy says it's not ... hmmm

 

Yes and no. The purge control solenoid and the EGR solenoid are identical except that they have different connectors. You should be able to remove the copper contacts/pins from the connector housing of either solenoid and put them into the other's housing. Otherwise you could splice the connector of one onto the other.

That came-up as the Purge Valve ... that's not the same thing is it? My parts guy says it's not ... hmmm

 

The parts guys is sort of correct. The description is incorrect at thepartsbin, but check the Product Notes in the description for B7079-60044 - it says "for EGR valve"

 

The Actual Purge Valve is part number B7079-121116

 

They are basically the same thing, anyhow. Purge Valve has a black connector, EGR valve has a white one, but if you hook them up, either would work. All they do is open and close.

 

I need to find the trick for the ecu into thinking it is good

The 68 ohm reisistor (or any similar sized resistor) will do that. No CEL; it will run fine.

To make it permanent, cut off the plug from the old valve, solder in the resistor, and plug it back into the harness.

I've had resistors in place of the EGR solenoid for a couple of years now without any problems. I just stuck the resistor into the harness plug and left it that way. I go through all kinds of snow, mud and water with the car. No problems at all.

I bought some pizza for the tech @ my local dealer & he hooked my '90 Loyale up to the computer - it threw code-34 "EGR Solenoid" .... went to my local parts store, and they don't even have an EGR valve LISTED (but they do have the gasket), and I see only minimal references to them here ... I search 20+ threads ...

 

Is it just me, or am I in for a world-of-hurt at the dealer? ....

 

This assumes the tech (who admitted he'd never worked on such an old one knew what he was doing ... he plugged his reader into an adaptor, and then into a yello DIN plug on the drivers' side by the firewall ..

 

(Gulp ....)

 

Looks like you got your info.

 

Only one additional note.

 

You don't have to hook your car up to a machine to get codes. All the stuff is there to do it.. built in to the car. THere are even instructions here on how to do it.

 

Might save you the cost of a pizza next time

Wow.

 

You guys rock! But you're light-years ahead of me on this stuff ...

 

I'm not honestly 100% sure (Hell, I'm not even 25% sure!) what I'm reading here....You mean to tell me I can throw in something like this:

 

 

... that I get from Radio Shack for fifty cents? Find the old one, swap them out with a soldering-gun (or more simple yet, a crimp-cnnection!) and I'm good to go?

 

No way ...

 

Now we're talking this is the EGR Valve, yes? Attached to the passenger's side of the intake manifold ... the one with NO WIRES hooked to it?

 

 

Now for the Solenoid, all I can figure is this:

 

 

I know it's a bad pic, but it looks like a small sugar-cube sized gizmo a little more towards the front & definitaly burried.

 

Is this what we're talking about here? And am I reading the suggestions correctly that I should buy a PURGE VALVE and cannibalize it for the solenoid?

 

I guess I needed to be treated like a little baby - I'm a newbie, afterall, hehe. Hope that get me a "Pass" and I don't need to be Clipped/Whacked by Pauly Walnuts for asking the same question over & over...

That looks like the correct solenoid to me. the purge solenoid looks just like it, does the same thing and is located within 6 inches or so of that EGR solenoid.

The vacuum solenoids are really common on lots of Fuel Injected vehicles. Just look around in the junkyard for something simaler, then cut the wires on it so you can spilce your connector on. I used a solenoid off of a cadillac coupe deville, classy if I say so myself.

Here is how to replace them with Toyota solenoids:

 

http://users.adelphia.net/~davidtief/solenoid.html

I know it's a bad pic, but it looks like a small sugar-cube sized gizmo a little more towards the front & definitaly burried.

Is this what we're talking about here? ...

Yes!

 

And am I reading the suggestions correctly that I should buy a PURGE VALVE and cannibalize it for the solenoid? ...

 

No - not correct. Forget all about the valve - just buy the EGR Solenoid, and replace it. again the part number is B7079-60044 at thepartsbin, if you want a new one. They just made a mistake in the description. The other replacement options you see here will all work too, and a lot cheaper - just find a similar one and replace it.

 

good luck!

If you do put a canister purge solenoid in place of the EGR solenoid, make sure that it operates identically. If I remember correctly, the EGR solenoid applies vacuum when power is applied, while the canister purge solenoid vents when power is applied. Their operation can be switched just by changing which ports the vacuum hoses and the little vent cover go on.

Bump.

 

Okay, replaced both solenoids, connected the white connectors under the hood to clear the code ... and wham!

 

Check engine light on again ...

 

Grrrr ...

 

And i'm still all dirty from the solenoid extraction!

Okay, that's creepy ... went on a test-drive just now & the "Charge" dummy-light came-on, just like it did when I lost a belt .. hmmm. The only thing I did was swap the solenoids & put in the 2 side-marker harnesses ...

 

Wonder if I screwed-up something trying to re-set the computer.

 

d'oh, that sounds just like my 88 GL.

 

I've replaced the EGR solenoid with known good ones, with resistors, checked the wires between the solenoid and the computer (good), looked around in the computer, and I still get a code for it

 

Soooo... I've just resigned to having my CEL on, and occasionally I check it for any other codes. This works since we don't have vehicle inspections where I live (yet).

I guess I don't know for SURE that I swapped a good solenoid with the old one. I'll judge by mileage. I'm getting 28 or so now - if it goes-up, then I'll just assume I did it right ...

The resistor REPLACES the solenoid. You just cut the pigtail off the end of the solenoid, and solder/heat shrink the resistor to the leads. Plug it in and you are done. Don't forget to plug the vacuum lines with a couple small bolts or BB's.

 

GD

The error code is generated when the ECU doesn't see the correct current flow in the valve circuit. This is why you can fool the ECU by swapping a resistor in place of the solenoid.

 

Since you replaced the valve with another one and the code didn't clear it may be the real problem is with the connection to the valve. It would be a good idea to check the circuit using a ohmmeter on the connector pin that ties to the valve at the ECU. You should see about the same resistance of the solenoid coil there as when you check it directly. If the connection looks good then the trouble may be internal to the ECU.

The error code is generated when the ECU doesn't see the correct current flow in the valve circuit. This is why you can fool the ECU by swapping a resistor in place of the solenoid.

 

Since you replaced the valve with another one and the code didn't clear it may be the real problem is with the connection to the valve. It would be a good idea to check the circuit using a ohmmeter on the connector pin that ties to the valve at the ECU. You should see about the same resistance of the solenoid coil there as when you check it directly. If the connection looks good then the trouble may be internal to the ECU.

+1, your original unit may be just as good as the other junkyard solenoid..

The error code is generated when the ECU doesn't see the correct current flow in the valve circuit. This is why you can fool the ECU by swapping a resistor in place of the solenoid.

 

Since you replaced the valve with another one and the code didn't clear it may be the real problem is with the connection to the valve. It would be a good idea to check the circuit using a ohmmeter on the connector pin that ties to the valve at the ECU. You should see about the same resistance of the solenoid coil there as when you check it directly. If the connection looks good then the trouble may be internal to the ECU.

 

If that's the case, do as I did with my conversion, and cut the leads next to the ECU and solder the resistor right there.

 

GD