Realtime: egr VSV replacement, and throttle body removal (1 Viewer)

[TLCgrappler]

Hi guys,

I'm doing the throttle body first, and have read the threads, but any gratuitous advice is welcome.

On the VSV, I see the bolt that can be remove with the long extensions from underneath, but looking at the part, it looks like that should be the only one?? The write-ups say you need to get a second one from above, but its not clear to me why (yet). The service manual drawing appears to show the vsv sittin in a little bracket that is secured to the engine block by two bolts. Do I have to undo one of these to remove it, or am I missing something. I'm obviously doing this without removeing the plenum, but it will be after I get the throttle body off.

Thanks for any input

 

[fzj80kidpen]

So why is it you are doing this?
Most just replace the EGR vacuum modulator (green top) and replace it with a new blue topped one. They are about $55 if I remember right. When I did mine I removed the EGR valve as well and cleaned it. Be sure to use penetrating spray on the pipe union on the very back as you do not want to damage that. Also be very careful of the engine wiring harness. I did not remove my TB so I can not comment on that.

 

[Rookie2]

Hi guys,

I'm doing the throttle body first, and have read the threads, but any gratuitous advice is welcome.

On the VSV, I see the bolt that can be remove with the long extensions from underneath, but looking at the part, it looks like that should be the only one?? The write-ups say you need to get a second one from above, but its not clear to me why (yet). The service manual drawing appears to show the vsv sittin in a little bracket that is secured to the engine block by two bolts. Do I have to undo one of these to remove it, or am I missing something. I'm obviously doing this without removeing the plenum, but it will be after I get the throttle body off.

Thanks for any input

It's been a while since I replaced mine (to rid the infamous P0401). If you've got the throttle body off, then you should be able to get to both bolts that hold the VSV bracket on, from the top side. I think you only really have to come at it from underneath if you don't remover the TB. Once you have the TB off, you should be able to see both bolts... IIRC, one is upside down (the one you could access from underneath with a bunch of extensions) and the other is at 90 degrees to it (facing the TB). Again, I'm going off a couple years of memory, but both bolts are definitely readily accessible from the top side with the TB off. A rachet wrench will make pretty quick work of it.


Rookie2

 

[TLCgrappler]

thanks for the replys

Im doing the vsv because i did the other parts months ago and still have the insufficent egr code with CEL.

Having gotten to the vsv after removing and cleaning the throttle body, it measure 18,000 ohms of resistance, as opposed to the 30-34 ohm specification. The new one measured 31, as it should, so I guess I can be reasonably sure this is the culprit. MOre later.....need to use remaining daylight to reattach throttlebody.

Later edit: All done, code cleared, and no more CEL.

The VSV for the EGT is attached by a phillips head screw to a bracket that is under the "plenum", or air intake. It took me about a half hour to remove the throttle body, which was dirty on the back lower half of the throttle plate. I frankly don't know how you could get to this VSV without pulling the throttle body first, although I guess some have done it. Its a mild PITA, but at least you can get your hands in there if they're not too large, and it wasn't tough to get a a Sears "ratchet flex wrench on the two bolts that hold the bracket into which the VSV is mounted. I can't imaging how you would get an ohmmeter on the contacts to check the resistance spec without removing it from the brackets first.
I happened to have a throttle body gasket on hand from a previously planned cleaning, so I finally got to use it. The service manual shows it as a mandatory replacement if you disassemble it.

 

[super90]

VSV

I pulled the top from in the intake manifold to get to the VSV, but it was a couple of years ago. Once the intake was apart it was easy to replace the VSV. It doesn't sound like you are going that far though.

It does sound like you have narrowed it down to that part. I have heard it can be replaced from below. You might span a couple of well padded 2x4's across your fenders and see if you can lay on them and reach under the intake to gain access. I find that sometimes helps when doing the fuel filter, which is in that same area.

I would be sure that the port that goes from the EGR valve back into the top of the intake is clean and is not plugged. Mine was plugged with carbon right at the opening to the intake, and that was the culprit of the insufficient EGR flow in my case. I think you might be able to shine a light into the intake through the throttle body and use an inspection mirror to look and see if that port is open in the top of the intake. It would be the cheapest fix of all, so I would want to rule that out first.

I did replace the EGR valve and the VSV while it was all apart, and all the vacuum lines too. I figured at ten years of age and 150k miles, these parts were worthy of replacement to make things right and good for another decade.

YMMV.