DIY: Camry 2.2L 2001 VSV for EGR Replacement

[mdmm]

Originally Posted by mustang67408

The EGR Modulator is located next to the EGR valve on the top of the intake manifold by the firewall, it has 3 vacuum lines going to it. Clean the vac lines and replace the modulator.
The EGR VSV is located on the back of the cylinder head under the intake manifold and is very difficult to access without raiing the vehicle.
PM me for more info.

Thanks alot.I will do it tomorow.Today morning i got the light back and am getting three previous codes, PO441,PO446,Po401.
I saw a sonsor behibd EGR valve in my Camry2000.It say"" Toyota , Sensory Assay , VAC, 89420-060 40 and at the bottom is a number, 0136 .
Please let me know what is this sensor about and Do I need to clean it or replace it also if it may be causing the problem ???

[mustang67408]

Originally Posted by mdmm

Thanks alot.I will do it tomorow.Today morning i got the light back and am getting three previous codes, PO441,PO446,Po401.
I saw a sonsor behibd EGR valve in my Camry2000.It say"" Toyota , Sensory Assay , VAC, 89420-060 40 and at the bottom is a number, 0136 .
Please let me know what is this sensor about and Do I need to clean it or replace it also if it may be causing the problem ???

That should be the EGR modulator, check it. It either passes or fails. Usually they need to be replaced along with the EGR VSV under the intake manifold.

[mdmm]

Originally Posted by mustang67408

That should be the EGR modulator, check it. It either passes or fails. Usually they need to be replaced along with the EGR VSV under the intake manifold.

Thank you very much SIR.
I will get and replace EGR Vac Modulator next week.One more question please.
I saw a sonsor behibd EGR valve in my Camry2000.It say"" Toyota , Sensory Assay , VAC, 89420-060 40 and at the bottom is a number, 0136 .
Please let me know what is this sensor about and Do I need to clean it or replace it also if it may be causing the problem ???

[mdmm]

Originally Posted by mustang67408

That should be the EGR modulator, check it. It either passes or fails. Usually they need to be replaced along with the EGR VSV under the intake manifold.

************************
Thank you very much Sir.
Under your guidance by pdf pictures and repair notes,I clean EGR Valve and EGR modules and conneted all tubings.since last 2 days code po401 is gone.Now i am only getting two codes po441 and Po446. Now what is suggestions,that a quite new person like me can do with minimum money matters,please.
Do I need to clean or replace VSV switch or valve.Do I need to clean or replace charcoil canister by new or used??
Where is charcoial canister located??Is it a big drum on back bottom of Camry2000???

[mustang67408]

Originally Posted by mdmm

************************
Thank you very much Sir.
Under your guidance by pdf pictures and repair notes,I clean EGR Valve and EGR modules and conneted all tubings.since last 2 days code po401 is gone.Now i am only getting two codes po441 and Po446. Now what is suggestions,that a quite new person like me can do with minimum money matters,please.

I would start by replacing the VSV that is desrcibed in the attached TSB.

[mdmm]

Thanks for nice reply and advice.But now I am very confused because all 3 codes, "" PO441,PO446,Po401."" came back after one week.So what to do what not to change.
EGR modulator or VSV valve or what.How much they cost ??

[mustang67408]

Originally Posted by mdmm

Thanks for nice reply and advice.But now I am very confused because all 3 codes, "" PO441,PO446,Po401."" came back after one week.So what to do what not to change.
EGR modulator or VSV valve or what.How much they cost ??

you have 2 different problems

1: P0401 is for the EGR problem, replace the EGR VSV and modulator

2: p0441/p0446 is a EMMISSION PROBLEM. Replace the VSV on the air cleaner box per the attachment I provided above.

[JRCARNUT]

I'm new to tundrasolutions.com and I found this forum because I was looking for some information regarding "Insufficient EGR Flow" (read by the ODB II) for my 4-cyl 1997 Camry. The information I found here was extremely useful, specially what parts (there are 3, i.e., EGR Valve, VSV, and EGR Modulator) usually go bad.

I want to share some additional information for those that might run into this problem. Like the forum said, the problem is typically the VSV or the EGR Modulator or both. The Modulator is a piece-of-cake to replace but the VSV is another story if you don't know the tricks. Here are some tips:
1. I started with the VSV
2. Jack up the right front of the car; remove the right front wheel; use jack-stands.
3. Once the wheel is off, with a flashlight, look behind the engine, RIGHT ABOVE the engine support. It is very easy to see. It has a blue electrical clip which you can easily pinch the plastic clip to release/pull.
4. If in doubt, crawl underneath the car and follow the two small hoses that come from the EGR Modulator and it will lead you to the VSV. However, from underneath the car, you cannot see the VSV.
5. BEFORE YOUR START to put your arm through the tight space, find all the sharp clamps, corners, bolts, etc. that your arm might scrape against. Use some tape, rag, or any material you can use to temporarily cover the sharp edges. This will save your arm/skin from a lot of cuts and scrapes.
6. You will need a 12mm socket or wrench but here's the tirck. The bolt is fairly tight and you can easily strip the corners and before you know it, your socket or wrench will no longer work/catch. As soon as I felt this was starting to happen, I used my air-rachet (was a little tricky getting it in the tight space to make sure the socket was well-seated on the bolt) and the bolt came off very easily. Not as powerful, an air-rachet has a similar rotating action as an impact wrench and it works great! If for some reason you drop the bolt on the engine support, you will need to use a telescopic magnet.
7. I mounted the new VSV with the same bolt but I used a lock washer so I did not have to make it too tight but certain enough that it will not come loose
8. I reset the ODB code but the check engine came back on again.
9. I replaced the EGR Modulator and all ODB codes were cleared. Problem solved! The car passed inspection.
Thanks to all that have posted information on how to fix this problem. Hope my additional tips will be useful to someone.
Jesse

[Paul Milenkovic]

I just replaced the EGR VSV on my 1997 Camry 4-cyl by going in from the top. Took me three days -- somewhat like Ahab's combat with the White Whale, although fortunately, I did not get dragged off to my doom tangled in vacuum hoses and wire harnesses. I think I know enough now that I could probably do another one in 2 hrs.

Before you start this project, get yourself a flexible-shaft magnetic pickup tool. I come from multi-ethnic origins, and there is a family story about some friend's kids being prompted "Say something in German" to my grandma, to which one child replied with the worst Serbian curse word. "Where did you hear such a thing!" "Oh, Daddy says that all the time when he is fixing the car and drops the wrench." You are going to drop wrench sockets, the VSV bolt, etc into the engine compartment, and there are two places to sweep to get them back -- in this pocket formed by an engine mount bracket right under the middle of the intake manifold, and also on the crevice on the front side of the steering rack. I payed 10 dollars for this tool at a well-equiped hardware store. You have that tool at hand, so you don't have to say any "German" words.

The other thing to do is park the car with the steering wheel turned left so you can lie down on the ground and peer in through the passenger wheel well to get an idea of the location of the valve. I did a lot of looking, wearing one of those LED headlamps, squinting past the various brake and power steering hoses in the way, but I didn't bother with lifting the car and the jack stands required if you do that. But it helps to identify some landmarks because the rest of this is done by feel.

The next step is to remove the bolt holding the VSV to the firewall side of the cylinder head. Others have recommended removing the electric connector first, but you are going to get bruised and scraped attempting this, and you will give up in frustration. The release tab (on the passenger side of the connector when the VSV is bolted down) requires goodly amounts of pressure, and separating the connector requires a firm pull, and you simply can't get your hand in there to do this, at least not without going in from the bottom with the car up on jack stands and the passenger-side front wheel removed.

I ended up using six inches of extension on an ordinary socket ratchet with the specified 12 mm socket. After dropping and losing and recovering stuff a bunch of times, I ended up using electric tape to hold the extension and the socket together -- perhaps higher quality tools snap together more firmly and don't have this problem. Getting the wrench, extension, and socket in position underneath the intake manifold is not too difficult -- the challenging part is locating the bolt completely blind and doing it entirely by feel -- if you don't have a helper peering in through the wheel well, do some more looking down there to get "the lay of the land."

Where you are aiming for is a spot along the cylinder head in the gap between the paired intake runners. There is a bolt you can see that attaches the valve train cover or such thing to the cylinder head, and below that is a triangular indentation in the aluminum head that you can probe with your extension, and right below that is a kind of ledge of aluminum that has a round island of aluminum into which is fastened the mounting bolt. Again, peer in through the wheel well with a good headlamp or flashlight to get a picture in your mind, and recreate that picture by probing with the wrench extension when working topside.

I ended up rounding the bolt with a 12-point socket because I got confused and set the ratchet for tightening. My poppa once scolded my for not knowing the right-hand rule for tightening and removing screws and bolts, but these days I rely on "righty-tighty lefty-loosy" that I learned on the TV "Millionaire" quiz show, but you have to set the ratchet before diving into the engine compartment not to get turned around. I found a 6-point socket but with only a 1/4" drive in my motley collection of tools, but after having strained to tighten and rounded the bolt, the loosening was a pleasant surprise that happened without much trouble. Maybe that bolt is tapered to "cam out" on overtightening so you don't strip the threads in that aluminum.

Of course I promptly dropped the bolt into that pocket formed by an engine mount bracket and the engine block, hence the magnetic retrieval tool -- I put a bend in the stiffening wire of the tool and dipped the errant bolt out from the wheel well.

Upon removing the mounting bolt, you can reach in from topside and maneuver the VSV to where you see it -- I was able to get two hands on it to remove that stiff electrical connector, and I removed the two vacuum hoses -- one took some plier persuasion to twist off. The vacuum modulator has three hoses topside -- two to the thottle body, the third one I blew into to find which vacuum connection at the VSV is modulator. I also blew into the vacuum hose pulled from the EGR valve proper to identify the second hose connection to the VSV that is the EGR valve.

Having the VSV removed, you can get at the terminals easily with alligator clips, and I used a 12 V DC HO-scale model train power pack to test the valve. It tested OK, but interestingly enough, I had to blow hard in the modulator hose to get it going when checking vacuum connections, so maybe there was some blockage there.

The vacuum "logic" of the VSV is that deenergized, that is with no juice applied, there is a vacuum connection from the modulator straight through to the EGR valve. It seems that the "default" operation of the VSV is to allow the modulator to operate the EGR valve. When you apply 12 V, there is a click. Now there is a "dump vacuum to vent" connection between EGR and this little air filter thingy on the VSV, and the vacuum connection to the modulator is blocked. This energizing the VSV dumps or vents the EGR valve vacuum to prevent the modulator from causing EGR to happen, and the modulator line is blocked to prevent a vacuum leak in the system.

When you put the new VSV in, you are going to have to get the hoses straight -- putting the VSV hoses in reversed will not operate the correct way. It is easy enough to test which hose is modulator and which is EGR valve by blowing on the tubes and feeling where air comes out. Also, the modulator is connected to the "passenger side" or "connnector side" of the VSV, and it has the longer vacuum hose that has been bent into a kind of shepherd's crook, and the shorter vacuum hose is the EGR valve connection to the connection on the driver's or little airfilter thingy side of the valve. The open hood has an EPA Emission Control decal showing the vacuum hose routing, and there is a kind of cartoon of the valve that shows enough detail to confirm these connection.

The other strange thing is that I thought, well, the VSV works, and if it fails, it is because there is some crud in it causing an intermittent condition. I squirted spray can carb cleaner in it, and then the valve failed -- the solenoid would buzz instead of click, and the inside spool was stuck in a position where all ports were blocked, hence the P0401 Insufficient EGR code. Before someone takes me to the wood shed for putting carb cleaner in something that gets wrecked with carb cleaner, the next day, the valve started working again. I am thinking that maybe the way this valve fails is that insulation or plastic gets baked from engine heat to coat the spool inside the valve, and that the failure in intermittent is that it takes heat (or solvent) to liquify that coating to make it sticky to get the valve to fail.

Getting the new valve installed is an even better opportunity for German practice than taking it off. It is easy enough to put the vacuum hoses the right way from what I have outlined, and you may as well click the electric connector in place while you have the valve angled to where you can see it. I routed the modulator vacuum hose over the electric line. I suppose you could just leave the valve hanging there, but once the vacuum connections have been removed, they tend not to stay on when you put them back on, or at least until vacuum and engine heat bakes those connections on. There was a suggestion to use an alternate bolt hole on the intake manifold to remount the VSV, but I didn't see anything on my 97 Camry that was within range of the short leash of the electrical connector.

Next, all of one evening and an hour and a half of the next morning were spent on the quest to get the bolt through the mounting bracket and screwed into the proper bolt hole.

What finally worked was to use electrical tape to not only tape my socket to my wrench extension, but also to get the bolt held firmly to the socket. There may be magnetic sockets to do this, but I used electric tape. You also have to get the bolt taped straight into the wrench socket or you are going to have trouble getting the bolt threads started into the bolt hole. Make sure the electric tape holds the bolt firmly or you are going to say things Grandma doesn't want to hear from a young man. Once you get the threads to take in the bolt hole, you can angle off the wrench extension to leave the bolt behind in its thread hole without getting electric tape stuck to the bolt.

Here was my five hours worth of work question -- we are back to Herman Meilville's whaling analogy of maniacal persistence. How to you 1) position the VSV, 2) get the bolt threaded through the bracket hole, and 3) get the bolt thread started in the mounting bolt hole.

What I finally came up with was that you get the VSV in some semblance of the final position by looking through the wheel well to see where you are and then going topside to jockey the VSV into position. As mentioned earlier in this thread, there are constraints on four sides, and you have to maneuver the VSV with two attached vacuum lines and one electric cable, and the VSV is bulky, with the mounting bracket sticking one way and that air filter thingy sticking another way, wanting to get hung up on the wrong side of a flange on that engine mount bracket that catches your dropped bolts and sockets.

I started with the taped up socket extension, socket, and bolt without attaching the ratchet -- once you get the bolt through the bracket and threaded into the cylinder head, coming back with the ratchet attached is easy. I also practiced with this rig and without attempting to thread the bracket, in the blind and completely by feel, locate the bolt hole and thread the bolt into it. If you have the bolt taped the least bit off center, this will frustrate catching the threads, and you have to know this now before even attempting to thread the bracket. This exercise will also get you a feel and also a topside look through the gap between the intake runners of where the bolt hole is located. When you feel around for it, it is on an island -- you have to feel for the bolt hole in that island, and you have to feel for the exact angle that gets the threads to grab.

Once you have this feel for putting the bolt in blind, you are ready to thread the mounting bracket and thread the attaching bolt hole. And you can jockey the VSV to where you can sort of see the mounting bracket in that gap between the intake runners, but in moving the VSV around, be sure you don't pull off one or the other vacuum hose -- they tend to slip off at this point and you are back to having Grandma want to wash your mouth out. With the bracket hole threaded, and with your training on how to locate the cylinder head bolt hole blind, you are ready to probe for that bolt hole, capture the threads, and now you can breathe a sigh of relief before getting the ratchet out and tightening the bolt. Do one final visual inspection from down below that the two vacuum hoses are in place. I had also threaded the passenger-side modulator hose over instead of under the electrical cable as having less interference, but your mileage may vary.

As a final test, I went topside and blew air through the EGR line and verified that air came out the modulator line, verifying that the hoses were connected and that the valve was in its deenergized pass-through condition.

Were I do this again, I might go the the hardware store that sold me the magnetic pickup tool to look over their assortment of inspection mirrors in a variety of sizes -- if I could get a view topside of where I was sticking the bolt, finding the bolt hole could be done without all of that probing and checking from below. Following what I have described, it is possible to change the VSV without jackstands or without scraping and bruising your hands and arms.

[omarq]

Excellent writeups guys... if it wasn't for this site... I would have never guessed about the VSV, found it, or been able to replace it.

You guys rock... P0401 is now gone!

-Omar

[jer37]

Originally Posted by mavic

Just want to add something to what kodyw posted. Instead of installing it at the same spot, there is another hole left of it and in clear view that you could mount on. I used that hole and bolt works.

(snipped)

mavic

I am new here and have the 401 code also. This comment intrigued me. My thinking is if there is another place to bolt the vsv to why not just leave the old one in place and install the new one in this alternate location unless there is not enough room for 2.

I have so far removed, cleaned and checked my EGR Valve and and reinstalled it. I also installed a new PCV valve. I have cleared the 0401 code and I am waiting for it to come back. So far so good. I also cleaned and checked the modulator and it seems ok.

I am very glad I found this forum and this thread because it will save me some money and that's good thing.

Thanks for all of the good info here.

jer37

[shet]

Thanks to all you guys. I was able to change the EGR VSV on my Camry 2000 (4 cyl). Some of the things I did are as follows:

1) Wore a thick full sleeved t-shirt (thanks to others earlier who warned about sharp corners)

2) Did not remove the front right wheel but turned it all the way to the left. Then jacked up the car.

3) Then removed the plastic thing just after the wheel (mud guard ??). See the attached image 1_wheel_well.JPG for that plastic thing's pic.

4) Used the tools shown in attached image 2_tools.JPG. From left, ratchet wrench, 20 inch extension bar (craftsman), universal joint and 12 mm socket. All are 3/8" inch.

5) Removed the electrical connector after going underneath. Remember to press on the tab before yanking it off. The left blue colored thing in the attached image 3_vsv_locn.JPG is the connector. And the right blue colored thing is the one on the new VSV. It took me a while to figure out the tab.

6) Removed the bolt attached to the VSV by lying outside on the floor near the right from wheel. The 20 inch extension helped. See the attached image 3_vsv_locn.JPG. This image is after I had connected the vacuum pipes the new VSV but before connecting the electrical connector and before bolting it. The jutting non magnetic tool has grabbed the part of the VSV which has the hole for the bolt.

7) Go underneath the car and do what others earlier have told about changing the VSV

8) While installing the new VSV, the bolt is difficult to put using the tools (even with the magnetic inserts I had). However, I was able to screw the bolt using my hands by going underneath and then tightned it by using the tools from outside. I inserted the bolt in the hole in the new VSV with index finger and then took the VSV near the hole in the engine block and then screwed it with the same index finger. I could not believe that I was able to tighten it with my hands and that too with restriction of using only one finger. I was really relieved that this step turned out to be quick for me.


9) Also get all the tools mentioned by others. I purchased all the tools mentioned in step 4) above as well as magnetic pickup tool, non-magnetic pickup tool, inspection mirror, magnetic inserts. For e.g. the mirror was useful while putting back the plastic thing which I removed in step 3 above

Best of luck to others.

Thanks
Diwakar

[jer37]

Well my 401 code came back so I replaced the Modulator and have been driving
for about a week now with no code. I also checked with my code reader and where I was getting a yellow lite I am now getting green.

I still have a problem though, the car misses and bucks now and then after
it has warmed up. Could this be an oxygen sensor going bad. I had those
symptoms about 4 years ago and replacing the sensor took care of the problem
but I do not remember if a code was generated.

I did buy a VSV valve but have not installed it yet, looks like I may have wasted
money there but I will install it anyways. Cant hurt.

jer37

[descomcu]

I've got code P0401 on my Toyota Camry 2001 56k miles. I did replace ERG Modulator for a new one but code came back on few days later. Next, I replaced the VSV for EGR following step by step in previuos post, it was vary helpful. I've been driving for about a month a no code has show up. I want thanks for helping me solve this problem with my car.

Has anybody experienced problems with gas pedal on Toyota Camry 2001 getting sticky ? Sometimes my gas pedal gets stuck and I has to put a lot pressure on it to get throttle.I did clean my Throttle body butterfly only with TB Cleaner and no major improvement noticed, any suggestions ??? thanks in advance