FSM scans for EGR VSV/Modulator testing? (1 Viewer)

[Pskhaat]

Got the infamous P0401. Reading the FAQs and other threads. Howevever, due to a gross oversight on my part for many years, I don't have an FSM for my 1996 FZJ80

FAQ says to test EGR VSV/Modulator per FSM. Does anyone have a scan or two of the appropriate pages for this?

Or link thereto

 

[reffug]

Order one it'll pay for itself many times over..........

 

[Pskhaat]

I am, just want to fix the EGR prob ASAP in the meantime.

 

[reffug]

Understood, would love to help unfortunately I'm at work and don't have my bible handy. I'm sure somebody will scan it in before I get home.

 

[Pskhaat]

Bump. Would anyone have a scan of the EGR test procedures? Wanna get this fixed and FSM won't be in for a while...

 

[landtoy80]

Have you replaced the modulator yet? What color is the top of it? The new and improved blue modulator is the one you want.
Is there carbon in the filter of the modulator?
If so then teating the VSV is a waist of time untill you replace the modulator with the blue modulator.
If you have carbon in your vacuum system, you will have intermittent failures of the VSV when carbon blocks the valve in the VSV.
Once you replace the modular with the blue one (if its blue now and full of carbon, replace it again) remove all the vacuum hoses, one at a time and blow them out. Cheak to make sure you ports on the intake are open too.
DON"T BLOW OUT THE VSV as it may damage the valve in it.
You will need the FSM to test the VSV as its best to remove the intake chamber to remove the VSV.
WIth the intake chamber off, you will need to clean up the carbon in the EGR port. You should replace the gaskets when removing the intake chamber. Some don't but do you want to take a chance on having a vacuum leak???

See, this is the reason you NEED the FSM when testing the VSV.

 

[turbocruiser]

A few things to add...

The FSM tells you how to test the modulator by blowing air in to one port while holding the others closed etc., buuuttt, it does not tell you how much air to use - the first two times I did this test I used air from the compressor at about 80 psi WAAAYYYY too much air, so, guess what, both my modulators were bad! - instead just blow through by mouth I simply took a long section (2 foot) of vacuum line and connected it one port at a time to do the test - you have to remember that the modulator is used to low pressures, probably always below twenty psi.

The VSV is easily removed from under the intake plenum by removing first the diagonal stamped steel brace bracket that supports the intake plenum. 80's prior to a particular year did not have this bracket making removal of the VSV even easier. I agree that removing the plenum is prefered but only because it makes cleaning the complete intake system much easier but if your intake is okay and you just want to work out the 401, you can save some time by leaving it on, again taking the time to clean the whole works is prefered but in my case, after the first, or let's see maybe it was the second time I "fixed" my 401, I thoroughly cleaned the intake so when the VSV popped after that, there was no need to remove the intake plenum. HTH

 

[Pskhaat]

landtoy, thanks for the info. We still got to get together for a when I'm up in New Lisbon area sometime...

[remote the] intake chamber

Do you mean the throttle body?

You should replace the gaskets when removing the intake chamber. Some don't but do you want to take a chance on having a vacuum leak???

I'm assuming you're talking about the gasket between the throttle body and the intake manifold? If not, which one again? Also, do you have a part # by chance?

 

[turbocruiser]

I'm assuming you're talking about the gasket between the throttle body and the intake manifold? If not, which one again? Also, do you have a part # by chance?

There are gaskets between the throttle body and the upper intake plenum, between the upper and lower halves of the intake plenum and probably also between the lower half of the intake plenum and the cylinder head although I have not removed that one so I cannot say for sure. HTH. P.S. Dan can provide all the above at great rates!

 

[Pskhaat]

One doesn't have to separate the top and bottom of the intake manifold (plenums) for this do they?

 

[fzj80kidpen]

Welcome to the club

I threw this code on my 96 a few months ago.
It does not take much carbon to clog those little holes.
I just replaced the vacuum modulator ( like previously said, no green old go blue new)
Removed the EGR valve. Tricky part, I learned a new respect for wd40. Spray some on the pipe union and let it sit over night then remove the next morning. I sprayed some throttle body cleaner in the valve and moved it around put it all make together. Went ahead and cleaned the throttle body while I was at it. I have been about 1500 miles since and no code return. I did not clean out all the vacuum lines to the intake but will return to that soon.
If you decide to go deep and remove the entake manifold then you might as well replace the fuel filter while its off.

Bill M
96 FZJ80KidPen
285/75 needing hardening

 

[turbocruiser]

One doesn't have to separate the top and bottom of the intake manifold (plenums) for this do they?

Yes, if you really want to clean them completely you at least have to remove the upper half of the intake plenum. IMHO you do not really need to remove the lower half of the intake plenum to clean it but as always, removal makes for superior results. FWIW, and this might be major shortcutting but with me I typically take the throttle body off and clean it completely and then with that thing totally cleaned, I reinstall, and manually hold open the butterfly while I repeatedly squirt some BG Air Intake Cleaner past the TB and into the intake plenums. I squirt for about ten seconds in all directions (past the butterfly, not on it) and then reconnect the intake plumbing and start the engine while revving it between 1500 and 2500 rpms. I repeat this until the cleaner is gone. I was surprised after searching it seemed like this would not work really well but in my case it worked amazingly well. I have one of those flexible fiber optic type flashlights and as I snaked it through the two plenums after this cleaning method I saw only shiny cast metal, no soot, no dirt, no debris, it was like new! I thought it would be wasting time to do the cleaning this way but apparently its not; even the tops of the tubes in the plenums were clean...I wonder if the pressurized intake/ forced induction with the turbo helps to have the cleaner blast all through the total plenum cavity? Anyway, hope that answers the question and hope that helps.

 

[landtoy80]

3fj40,
Do you think we could find place to drink in NewLisbon, we may have to go to LindonStation?
Depending on what year FSM you have the intake chamber/plenums is the BIG aluminimunuiumnun thing that goes to the intake manifold.
If you are going to remove the intake chamber, you may as well seperate the throttle body and intake chamber.