EGR Trouble

[bcossa2001]

1997 Toyota Avalon, 183K...

Check engine light came on--code shows EGR trouble. I checked the EGR valve per the Haynes manual--run engine, disconnect vacuum line to EGR, attach manual vacuum line, apply vacuum: if the vacuum is steady and the car runs poorly then EGR is ok. That is what happened.

I would like to check the vacuum switching valve to see if vacuum is getting to the EGR valve--since there is not supposed to be vacuum at idle, how can I do this??

 

[StevieC]

Disconnect the vacuum line to the vacuum switch and plug it with a screw and attach your manual vacuum line to the switch and apply vacuum if the engine starts stumbling you will know that it's getting vacuum at idle and the switch is defective.

 

[artificialist]

The plastic components in the vacuum system will shatter like glass in your old Toyota. Buy some brass tubing nipples, and heat them up, insert them where the plastic tubing nipple was, they will then melt into the plastic and create a new mounting point that is durable.

And now would be the time to replace the vacuum hoses, odds are some are leaking.

 

[bcossa2001]

Well, the CEL light turned off by itself on the way to work this morning. This has been happening (light on for a while, light turns off) for the past few months. Guess I'll wait until it comes back on to do more troubleshooting, although I am going to check the VSV as suggested above.

Replacing the vac hoses seems to be an excellent suggestion.

 

[StevieC]

If it's intermittent like you say I would be more inclined to think you have a leaking vacuum line or the switch is the problem.

Check all your lines and then check the switch and replace as necessary.

Good luck!