[Splieslife]

Hello,
I’m an intermediately skilled mechanic. I have a California emissions 95 Camry 2.2 that has an erratic idle when warm. After going through IAC valve and other first checks including replacing aging vacuum lines, all signs point to the EGR and EGR Vacuum Switching Valve being the likely culprits.
I wanted to buy a Toyota EGR VSV so I could move it to the firewall. However, Toyota tells me that the California emissions EGR VSV (Toyota #25860-74160) is discontinued and a brief search on the internet indicates this part is hard to find.

Above is a diagram that I obtained from the dealership. The top is federal, the bottom is California. You’ll notice that the two parts look different, the California part looks like two of the federal parts stacked on top of each other. Conversation and limited research has indicated that the California EGR VSV may have a third vacuum line going somewhere. It’s been hard to find information or a video that is specific to California emissions.
I’m just looking for insight and suggestions on locating this part. Some sites will indicate that their part will work for a 25860-74160 such as this;

https://www.sixityauto.com/aisin-vs...0-3092000871.html?find=1995-toyota-camry-3753

I’ll probably scoop this part and give the firewall move a try. If anyone has any info on differences between California and federal EGR VSV and related vacuum hose routing, it would be very helpful. As you all know, the EGR VSV is in a difficult location; my goal had been to just unplug the electrical connection and plug back into my new part on the firewall with the two lines going to the EGR and EGR Vacuum Delay Valve as is standard with federal emissions.
Worst case, I can always try to move my current part, but this just seems like a pain. I also would be hard pressed to know exactly where any third vacuum line was going to, should it exist (the working area is very difficult to access).

I appreciate your time for the long read, thank you.

 

[Splieslife]

Hey,

I spent half an hour writing a detailed response only to have it get deleted after being prompted to sign in.

Thus, I'll be brief.

Thank you for your help. I'll try the Aisin part I linked. I'll likewise clean the EGR and follow up.

I'll trouble shoot some of the other systems you mentioned.

Cheers

 

[Splieslife]

Hello,

Still have yet to dive back in on this one but I'll briefly provide clarification for my attention to the EGR system;

The car has been in my family since 1995. My parents owned it and for the last 10 years its been sitting mostly idle in their driveway. My parents ran it every couple months and kept up with maintenance, but it was barely used. A few years back it developed this wandering idle when warm and was only ever periodically warmed up afterwards (they didn't want to drive it far). My dad and a friend who's a veteran Toyota mechanic have chipped away at the issue on and off for years(it was low priority as my parents have other vehicles). They've replaced and gone through many of the obvious culprits for idle trouble; IAC valve, ECT sensor. The only system that they had not addressed was the EGR and vacuum lines.

A few weeks back, my current vehicle began to show signs of going soon, so I bought the Camry knowing its history. I replaced all the vacuum lines that are easy to access, cleaned the throttle body and generally gave everything a liberal hit of carb cleaner, short of opening up the EGR. I also hit all connections with contact cleaner and then dielectric grease. The EGR and EGR VSV are some the only untouched systems left.

I know the car was running great in years past (currently only has 160k miles) and in my experience valves like the EGR can easily become stuck through long periods of disuse. The EGR VSV is difficult to address in it's current location (I can't properly inspect the state of those vacuum lines) so I plan to move it in conjunction with a cleaning of the EGR.

If this is fruitless I'll look into the O2 sensors and possible air in the coolant as my friend above stated.

I'm confident it's the EGR as the car is incredibly smooth for the first 15 minutes of driving before the wandering idle begins. After, cutting the throttle causes the RPM to rove between 500 and 1000rpm. The steering wheel also shakes mildly when I cut throttle. Applying throttle smoothes everything out. When I come to a stop, the car can die if the idle is allowed to dip too low. If this happens multiple times in quick succession, then the car is difficult to start like the engine has flooded. My theory is that the EGR is stuck open or closed, causing the computer to dump more fuel when the O2 sensor is indicating an incorrect fuel mixture.

To summarize, I'm in a unique situation where I have a ton of information regarding the cars history and what has already been addressed.

 

[Splieslife]

Hey,

So I've only taken it for a spin once since I've acquired it. This was after I had replaced all the vacuum lines as described above (battery had also been disconnected during all of this).

I drove 6 blocks to the gas station, then a mile to a station that has a free air pump, then half a quarter mile to the freeway. I then drove three or four miles on the freeway to where I exited to turn around. Thats when the idle issue kicked in.

I only suspect the EGR as the car is very smooth prior to warming up. I would imagine that an issue with the injectors would be constant, but I could certainly be incorrect.

Which vacuum hoses do you specifically recommend disconnecting on the EGR and do you leave them open or seal them with a clamp?

Cheers.

 

[Splieslife]

Hello all,

Great news, I plugged the vacuum line that goes from the EGR VSV to the EGR and the idling problem went away. My new EGR VSV is coming tomorrow which I will be relocating and rerouting.
The only other issue to report is that the intermittent wheel shaking is still an issue. It comes and it goes.

 

[Splieslife]

Alright, so further updates;

I installed the new EGR VSV and relocated it onto the plenum. When I fired up the car the problem came back unfortunately, though it felt slightly less severe. I’m going to clean my EGR and investigate the booster.

I’m hoping it’s not an electrical issue somewhere making the EGR act up. When I unplugged the vacuum going to the EGR, the car ran perfectly.

 

[Splieslife]

Hello and thank you for your detailed response. I’ll address 93Celicaconv;

I’ve viewed several vacuum routing diagrams and have replaced all hoses except those than run from the EGR booster underneath to the two ports on what I believe is the exhaust. As mentioned before, I moved the EGR VSV to the top of the plenum.

My next planned move was to remove and clean my EGR valve. I’ve already vacuum tested the diaphragm (it’s holding vacuum fine). Unfortunately the 24mm crows foot that I ordered was stolen off of my front step by a package thief and I’m waiting for a new one to come.

I’ll briefly address some other systems that I’ve serviced;
-all new spark plugs
-coolant flush and change to HOAT coolant w/ new radiator hoses
-air filter replacement
-oil change
-PCV change
-added fuel injector cleaner to fuel
-throttle body removal and clean
-IAC was replaced with oem unit by my family
-they may have possibly replaced the throttle position sensor, not sure if they would’ve recalibrated it, I’ll need to look into this.
-they replaced the coolant sensor, I think it may not have been OEM, I’ll also need to follow up on that

As mentioned before, deactivating the EGR by removing the vacuum hose to the diaphragm fixes the problem. I’ve had to commute with it deactivated this way all last week for my freelance job (100 mile round trip). I’ve noticed poor mileage; close to 23mpg with mostly freeway driving, I’m not driving aggressively or heavy on the throttle. Also there’s a rush of air either in or out of the gas tank when I remove it to refuel. I understand this could be a symptom of the deactivated EGR not allowing the EVAP system to function(or it could be a clue worth looking into).

As you say, EGR is likely not the source of the problem. I still plan to remove and clean it so that I can rule it out as a possible issue.

I’ll look into the throttle position sensor (calibration as well) and the coolant temperature sensor. Is there any simple way to diagnose an ECU as being potentially faulty? My imagination would be that these are expensive and difficult to change; I’ll do some research.

Aside from not being able to pass emissions, is there any negative effect to continuing to drive with the deactivated EGR? Am I going to ruin my Catalytic converter by sending unburnt fuel into it?

 

[Splieslife]

Hello all,

Thank you for your patience waiting for my reply; I’ve been busy in the shop.

I have solved the issue, the idle is completely normal now. It ended up being the EGR modulator (and possibly replacing the EGR VSV contributed to the fix as well). The EGR modulator is one of the only parts available from Toyota, so I figured I’d throw a new one in. It set me back $110 (I’m not normally a throw new parts in guy) but thankfully the gamble paid off.
The car runs great. I really appreciate all the input and contributions from everyone. No doubt that some of the other suggestions will be helpful to others who don’t have my exact fix.

To summarize my symptoms and the fix;

Idle was erratic once the car was warmed up and had been driven for 10-15 minutes. It fired up fine and ran smooth prior to this. Once the idle became erratic, I would have to apply throttle to keep the car from dying at stoplights.

The route fix was;
-Replaced the EGR modulator with OEM factory Toyota part
-(may also have contributed to the fix) replaced the EGR VSV with a unit made by Aisin (makes parts for Toyota)

Other things I did that could have contributed to the fix;
-used contact cleaner and then applied dialectic grease to all connections relating to emissions, fuel/air, throttle, ect
-replaced as many vacuum lines as was practical (almost all relating to the EGR system)
-replaced coolant with new HOAT coolant
-replaced spark plugs with laser Iridium
-replaced radiator hoses
-changed oil
-replaced PCV valve
-IAC valve was previously replaced
-Cleaned throttle body
-new air intake filter
-applied dialectric grease to the battery terminals
-ran red line fuel cleaner through the fuel

That about sums it up.

I’m not in the process of;
-replacing all struts
-replacing all cv axles
-replacing all brakes and rotors, swapping rear drum for disc
-replacing numerous broken handles

The car only has 165k miles, wish me many hood driving years, cheers!

 

[Splieslife]

I’m am in the process of replacing those last items (not was a typo)

cheers!

 

[Splieslife]

Hello there,

So I’ve got bad news. After a couple hundred miles of smooth sailing, the idle problem has returned, though thankfully, it seems very infrequent.
It started again after I was testing the ECT function which delays transmission shifting and allows the engine to rev higher. I hopped on the freeway with the ECT engaged, hit 4,000 rpm getting onto the freeway, and then almost immediately noticed a subtle irregular feeling. I took the next exit and found that the problem had returned.
This seems to happen once per long drive. I’ve discovered that if I pull over and turn the vehicle off for ten seconds, the problem goes away.
In an effort to address this I replaced my coolant temperature sensor with an OEM one from the Toyota dealership.
I’ve also replaced the following:
-thermostat with OEM
-both accessory belts

I still need to;
-clean the EGR
-test the TPS to make sure it’s within the correct voltages
-replace the two vacuum lines that run from my EGR system, under the engine, to the upper coolant port
-I also want to investigate the port that these connect to make sure it’s sound/not compromised
-I need to double check all the coolant lines running to and from the IAC valve

 

[Splieslife]

Hey,

Yes, I actually read the other linked thread about the sticking EGR. I just ordered a new EGR valve from Napa. Gunna throw that thing on when it comes on Friday.

Overall though, my MPG has improved from 22.5 to 28mpg. Hopefully this EGR seals the deal, because the car otherwise is doing great!

 

[Splieslife]

Hey,

I work in cinema so I have very little time once work picks up. I gotta just get this thing buttoned up ASAP.

 

[Splieslife]

Hello all,

New EGR from Napa has solved the problem once and for all. As some of you mentioned, I may have been able to clean the stock EGR but I’m short on time and wanted to do a one time fix. The part from Napa was $250 but will be worth it if I don’t need to work on the system further. Thanks for all your help, I may invest in silicon hoses in the future.