Want a second opinion on my VSV diagnostics

[john_eckels]

Like everyone else on this forum, I have an P0401 CEL. After checking the modulator, I sucked on the tube to the EGR valve and the engine died, so I assume that the EGR valve works. I then felt the metal tube on the EGR valve and it was luke warm. I disconnected the line that runs from the EGR valve to the intake (I think the VSV line), held my finger over the EGR valve connector that I removed the line from, reved the engine for a while. The metal tube is now hot. EGR must be working now, or at least exhaust gas if flowing. I then sucked on VSV line at various engine rpm's and it always appears to be open. I am 90% sure that I have a VSV that is stuck open. Is there Anything else I should look at before giving C-Dan ~ $125 for a new VSV? Also, I really do not want to remove the intake and saw that there are a couple of success stories with using a 3' extension method. Does anyone have a link to a good thread? I tried searching and it is like finding a needle in a haystack. Finally, if I decide that this is too hard for me to fix, will the lack of EGR make the engine run too rich and fowl things up? Thanks in advance for your suggestions.

 

[Proven]

If I am reading the manual right (I still have the page marked, lol) you should get air flow without any voltage to the VSV. You should get NO airflow through the VSV if you HAVE voltage applied to the VSV from a 12 volt source.

The side that you can see coming through the intake up to the VSV is pushing air into the EGR if I read the schematic right and I remember what I was looking at.

Two things I found when I had to do this famous repair:
1- The passage way through my intake (the metal tube that bridges the hoses) was plugged with "crud" I won't confirm it was carbon, nor deny it was dirt...so it is just "crud". Once I removed the intake I took a drill bit and waller'd it out clean again.

2- The VSV was frozen with rust. The cheap metal pieces inside had corroded thus causing it to sieze.

The previous owner said she had the Check engine line for a long time and since her state isn't a smog state she never worried about fixing it.

Be aware that there are two vacuum valves under the intake. You want to mess with the ORANGE one and not the BLUE one. So if you read the part number off the ORANGE one to the guy at the parts counter he should sell you another ORANGE one and not a BLUE one like my hero did. I got all the way home and forgot the golden rule...LOOK AT THE PART AT THE PART COUNTER TO ENSURE IT LOOKS LIKE WHAT YOU WANTED!

So...I hope you found this informative....

 

[john_eckels]

I want the one that is hard to get to. I am sure C-Dan has the part number memorized.

 

[Sanchez]

I replaced mine last week and let me tell you it wasn't an easy task for me. I tried the long extension method from underneath. I only got to one bolt. I had to remove the throttle body to get to the other bolt. I tried looking for the other bolt from the bottom but I couldn't find it. I bit the bullitt and took the throttle body off. To my surprice it wasn't that complicated. I reccomend you take the throttle body off just to make things easier on you. I was able to remove the bolt with an open end wrench after removing the throttle body. One thing I found a little difficult (For Me) was removing the small hoses that are attached to the unit itself. This is where removing the throttle body helped me.

 

[alia176]

This pic shows the VSV well!

 

[MoJ]

This pic shows the VSV well!

I have the TB off (but haven't removed intake) on my 94 right now and thought I'd order an egr vsv while I was at it. Looking at this pic and comparing it to my 94 there appears to be a couple of other components on my 94 mounted to the same plate that the pictured vsv mounts to. Is anyone familar with a difference between 94 vsv and later years or was something not installed in this pic?

thanks
jason

 

[john_eckels]

I tried the long extension method from underneath. I only got to one bolt. I had to remove the throttle body to get to the other bolt. I tried looking for the other bolt from the bottom but I couldn't find it.

I dont think I every saw that bolt. After moving the support bracket out of the way. I suck my hand under the manifold and I could feel the bolt. A 12 mm ratchet wrench made removal easy. If you have huge hands, they may be a difficult task.

 

[billmiranda]

hmm,.. there is no blue and orange at my parts dealer... I got the one that had the serial number pictured on one of the threads here... 12079 I believe... it's black.

Havne't installed it but also got an EGR modulator and stuck that on... haven't had my light on for days... but the damn 7 step dignostics haven't finished... where as before I had a CEL,.. and the P0401,.. when I scanned my system,.. Everything except egr compnents had passed... now,.. I have no CEL and the first 6 steps are done,.. and passed,.. but the catalyst test hasn't finished... have to get this thing emissioned before neext week when I leave the country.