Check engine light: EGR troubles

[arcas]

Okay. So my CE light came on this evening. Pulled in to Autozone and had them check the code figuring it was the O2 sensor that has been acting up lately. Nope. This time it looks like the EGR position is wrong.

I've never dealt with an EGR valve before so this is pretty much uncharted territory for me. I suspect that the valve's pintle is stuck thanks to carbon deposits. Given that the vehicle (a '97 Honda Passport (~=Isuzu Rodeo)) has 45k miles, I wouldn't be surprised if the valve's vacuum port is also clogged. From what I've been able to gather this evening, it's usually sufficient to just clean the valve and port with a special intake cleaner spray (am I correct in assuming that regular "Gumout" carb cleaner will damage an O2 sensor?) rather than replace it outright. I won't have time to do that until maybe this weekend.

My question: is the vehicle safe to drive until I get around to fixing this? The Autozone guy seemed to think this wasn't a big deal but I'd like a second opinion

 

[Pepsi90919]

yes

 

[Maximus96]

its safe to drive. you just won't pass smog test, if you were to bring it in to test.

 

[Wingznut]

If the pintle valve is stuck open, the engine would idle horribly. Presuming it's not that, then more likely it's either not getting vacuum, or it's not holding vacuum.

I've seen many occasions where the code is a "fluke" or basically a one-time occurance. First thing I'd do is clear the code and see if it comes back.

Again... Presuming the engine's running ok.

 

[arcas]

Thanks. I'll disconnect the battery to reset the code and see what happens. Engine seems to be running fine (so far).

 

[redly]

I have found automotive forums .com to be very helpful in discussing and diagnosing problems with my vehicles

 

[Maximus96]

is there a better way to reset your ECU other than disconnecting the battery? I don't know about hondas, but on nissans there is a scew on the ecu itself that you turn to reset. usually you need to leave the battery disconnected for a long period of time before the ecu resets itself.

 

[tomstevens26]

Well, only speaking from personal experience, my wife's service engine light came on back in early September. Also took it to Autozone and got the same diagnosis as you. The guy said the same thing...shouldn't hurt anything to drive it, it just probably won't pass the emissions test when it's time.

She's been driving it since that time without any trouble. Sometimes the light goes out, but comes back on later. We won't have to take it through emissions testing until May and we might sell the car before then anyway, so unless it starts causing problems she'll continue to drive it like that.

But like I said, YMMV.

Tom

 

[Toastedlightly]

Run some seafoam down it if you think it is carbon deposits. 98 Grand Prix had same problem.

 

[Pepsi90919]

Originally posted by: zaku
is there a better way to reset your ECU other than disconnecting the battery? I don't know about hondas, but on nissans there is a scew on the ecu itself that you turn to reset. usually you need to leave the battery disconnected for a long period of time before the ecu resets itself.

depends on the car. most OBD-II vehicles you have to reset it from the scan tool.

my taurus, you have to be running in diagnostic mode (jumper from one pin to another) and then remove the jumper and put it back in again, that clears all KAM/continuous memory codes