[dadu]

Did you try to swap them, only one seems to be connected to the servo.

If the one already working(and not cleaned) was connected then perhaps a same treatment to it.

But as I posted earlier, they are not repairable.

[RedMM340]

Originally Posted by RedMM340

Hi,

I am not an expert on the Hyndai diesel motor, nor have I ever looked under the hood of one.

But it sure looks like that setup is part of an Exhaust Gas Recirculation system. I would try and see if it was possible to plug the vacuum line going down to the round disc shaped vacuum diaphram. This would keep the EGR valve closed at all times, and give you more power.

Those solenoids are electrically controlled valves that allow the vacuum circuit to pull vacuum on the EGR valve. If they are stuck open you will be getting exhaust gas recirculation at all times, which will lower power. But rather than trying to repair it, I would see if it is possible to push it shut permanently. Then pull the vacuum line going to the EGR valve, and you will have more power and not spend any money.

Good luck,

Gaurav

Another idea: Just leave the solenoid alone. Pull the vacuum hose and plug it with a good airtight plug. Make sure it is airtight otherwise your brakes will be affected.
This will permanently leave your ERG valve shut regardless of the solenoid condition.

[AbhiJ]

Dadu, tried that as well, and strangely it didn't work. Maybe I killed the semi working valve

Originally Posted by badri

Do you need to replace both the valves or only the one that is stuck?

apparently they come as a set, and also, the service advisor said that one valve is dead, and one is sticking.

Originally Posted by RedMM340

Another idea: Just leave the solenoid alone. Pull the vacuum hose and plug it with a good airtight plug. Make sure it is airtight otherwise your brakes will be affected.
This will permanently leave your ERG valve shut regardless of the solenoid condition.

Good idea dude....

Plugging them well should be easy.

So if I plug both the black hoses (I checked, they ARE vacuum hoses) my brakes start working?

Also, what is the function of the other hose, other than the one you pointed out?

[RedMM340]

Originally Posted by AbhiJ

Dadu, tried that as well, and strangely it didn't work. Maybe I killed the semi working valve



apparently they come as a set, and also, the service advisor said that one valve is dead, and one is sticking.



Good idea dude....

Plugging them well should be easy.

So if I plug both the black hoses (I checked, they ARE vacuum hoses) my brakes start working?

Also, what is the function of the other hose, other than the one you pointed out?

Hi AbhiJ,

Plugging the black vacuum hose going to the solenoid will eliminate the solenoid and subsequent devices from the vacuum circuit. The EGR valve should be normally closed. It opens when vacuum is applied (via the solenoid & electronic control). By plugging the vacuum hose, the EGR will always be closed.

This should keep your vacuum circuit in tact, therefore not affecting the brakes (which use the same vacuum source).

The EGR is a pollution control device that opens the exhuast manifold to the intake manifold, thereby sucking exhaust gas into the intake. Typically the EGR will open at full throttle. With the EGR bypassed, you should get more power, better average, but a bit more smoke.

Not sure of the other vacuum hose, since I cannot see where it is going in the picture that you posted. Perhaps you can post a pic that shows where it connects to.

Best Regards,

Gaurav

[AbhiJ]

Thanks for the info Gaurav. It really clears things up!

Better Average??

The whole investigation began due to low average and the Hyundai Service diagnosed the PCSV's as the cause for low avg.

So if I seal up the vacuum hose, where will the exhaust gases from the other pipe go... ? I am assuming that the tubes with the green stripes pumps exhaust gases into the valve... right?

Is it safe to release them into the engine bay (possible fire hazard?)

[AbhiJ]

My query to RedMM340 ... illustrated

[AbhiJ]

Thanks a ton RedMM340

I tried the method you mentioned by sealing off the vacuum pipe, and it worked perfectly! My brakes are back to normal!

My only concern currently is, what happens to the gases coming out of the exhaust manifold? If they are getting released at full throttle as you suggested, is it safe for them to be released inside the engine bay?

[rider60]

Originally Posted by AbhiJ

Thanks a ton RedMM340

I tried the method you mentioned by sealing off the vacuum pipe, and it worked perfectly! My brakes are back to normal!

My only concern currently is, what happens to the gases coming out of the exhaust manifold? If they are getting released at full throttle as you suggested, is it safe for them to be released inside the engine bay?

well they being released in the bay might not be safe after all even i am watching this thread closely enough for a reply redMM340 are you listening?

[headers]

the gases released in the engine bay should not pose any problem IMO.

Redmm..whats your POV?

[RedMM340]

Originally Posted by AbhiJ

Thanks a ton RedMM340

I tried the method you mentioned by sealing off the vacuum pipe, and it worked perfectly! My brakes are back to normal!

My only concern currently is, what happens to the gases coming out of the exhaust manifold? If they are getting released at full throttle as you suggested, is it safe for them to be released inside the engine bay?

When the solenoids' vacuum source is blocked, they will not be able to open downstream EGR valve(s). This means that the EGR valve(s) will be closed, and all exhaust gas will flow out of the exhaust manifold and vent through the tailpipe. No exhaust will be recirculated into the intake.

[headers]

Originally Posted by RedMM340

When the solenoids' vacuum source is blocked, they will not be able to open downstream EGR valve(s). This means that the EGR valve(s) will be closed, and all exhaust gas will flow out of the exhaust manifold and vent through the tailpipe. No exhaust will be recirculated into the intake.

Which means -
1. Does the car fail the emission tests ?
2. Does the FE get affected?

[RedMM340]

Originally Posted by headers

the gases released in the engine bay should not pose any problem IMO.

Redmm..whats your POV?

Not sure what you mean by gases released in the engine bay?

Exhaust gases released in the engine bay would mean smoke billowing out under the hood right?

Please clarify what your definition of "gases released in the engine bay" means.

Thanks,

[headers]

Originally Posted by AbhiJ

Thanks a ton RedMM340

I tried the method you mentioned by sealing off the vacuum pipe, and it worked perfectly! My brakes are back to normal!

... If they are getting released at full throttle as you suggested, is it safe for them to be released inside the engine bay?

Originally Posted by RedMM340

Not sure what you mean by gases released in the engine bay?

Exhaust gases released in the engine bay would mean smoke billowing out under the hood right?

Please clarify what your definition of "gases released in the engine bay" means.

Thanks,

Hope this clarifies your question?

[RedMM340]

Please look at the attached pic.

1 = vacuum line in
V1 = valve 1
V2 = valve 2
V1i = valve 1 inlet
V1o = vlave 1 outlet
V2i = valve 2 inlet
V2o = valve 2 outlet
2 = unknown line
3 = EGR vacuum actuator

You say that you plugged point 1 and your brakes work. Good. By doing this you have disabled V1, V2, and 3.

Please find out where line 2 runs

I would leave all other vacuum lines as they are. Don't pull any more lines and plug. See how your engine runs. Do you have excessive smoke? Is the fuel consumption o.k.?

Please carefully monitor how your engine is functioning, as newer diesel engines do have complex EGR systems, and I don't want you to damage something in your engine by plugging point 1.

[RedMM340]

Originally Posted by headers

Hope this clarifies your question?

No it does not. I really do not understand.

No exhaust gas should ever be released in the engine bay.

Abhij, can you clarify since you said it first?