1995 Toyota Camry EGR sticking?

Try Autozone to see if they have a free loaner MityVac pump. Use it to operate the EGR valve to full engine vacuum several times quickly and see if you can knock some carbon off and get the valve to close in minor cases.

Test the EGR valve using the pump and see if the engine stalls. EGR valves don't usually go bad. You just have to clean it in rare cases.

Could also be a vacuum leak or a sticking IAC valve. Use the MityVac and see how strong the vacuum is when you are having problems. I think normal should be 17-22".

Have you ever changed the timing belt?

snipped-for-privacy@comcast.net wrote:

Timing belt was changed out about 10k miles ago. That would be... scary... to say the least, if it were that.

Plugs changed also. Also, both front side oxygen sensors (not the catalytic monitor, after the catalytic converter).

What has not been done is valve lash, which is daunting, from what I can see of the procedure. Basically have to strip the entire throttle assembly and plenum to do that. I am not sure... would bad valve lash present a symptom similar to this?

That thought occurred (and I suppose a valve lash will have to be done sooner or later), but it would not present as an intermittent condition if it was valve lash, I wouldn't think...?

IAC valve is a real possibility. That would not code if it's sticking, only in case of electrical failure. Friend of mine's 4 Runner had that, but the idle in his case was erratic and prone to dropping off during starting.

I tried the knocking things loose technique, using a length of hose and... just... sucking on it like a straw. EGR holds vacuum (diaphragm is OK). It did not sound as though it was moving at first. After a while, you could finally hear the pintle whack into the seat when vacuum was released, little metallic click. I haven't had a chance to road test it since then.

My thought was it was stuck just a little bit open, and exhaust gas was getting through. However, for this theory to be true, a few other things also have to be true...

First, the car can't be able to throw a P0401 / P0402 code... Too little / too much EGR gas. It can't have a monitor for this condition, or I would think it would have coded already.

Second, whatever the EGR is dumping in can't be enough to cause the fuel trim to go out of range. It must be small enough that the injector could compensate, or you'd get a code once again.

So first of all, in my thought process here, and for future reference as well, does the car have the ability to throw a P0401 / P0402 code?

Second of all... how do you clean up an IAC valve... and how can you tell if it's sticking? I've never looked at one, just seen the effects of a failed one on my friend's 4 Runner.

My '95 Camry pulled a P0402 code. I replaced the ERG value and the code disappeared for about 10 miles then came back on. I am going to air compress the hoses next.

Does anyone have any other ideas besides spending another $80 for another modulator/sensor/VSV?

Thanx, Cathie