So today I got off work. I started my car and let it warm up for about 2 mins. I drove for about a minute and the damn check engine light comes on. I've only had this thing for about 3 weeks and I'm not even trying to go through this route. Anyways i got home and plugged in the obd2 scanner and it gave me a p0402 Exhaust gas recirculation flow excessive detected... Can you guys please help me out. I have a 97 5sp if that helps any. Thank you

 

On my 97 auto I had that come up. I was planning on removing the whole egr valve assembly and doing the resistor trick so the ecu thinks it's working fine. I never got around to doing it though because the car was totalled. Do a search on egr valve and it should come up. If you plan on boosting it, then it's a good idea to eliminate it all together. But you're in Cali so you have all that smog testing.

 

Yeah, mine did that too. Turns out the engine was trash - excessive blowby from running too much boost. That's probably not your issue.

 

Yeah no boost in mine. I wanted a stock ride to stay away from all these problems and now i have a check engine light. I just bought the car, will i have to smog soon?

 

no one has ever had this problem?

 

LOTS of people have had this problem - try searching.

Also, verify all your vacuum lines are in good shape and properly routed. Remove your EGR valve and pipe and clean and inspect them both.

There is an entire procedure for checking the EGR system. I'm sure if you searched, you could find it.

 

to the original poster: Did you figure out what it was and did you get it fixed?

EGR related issues tend to become common as our cars age.

I drove for a while with a P0401 (EGR insufficient flow). It turned out to be the EGR modulator (plastic pod). It had a hole in the internal membrane. The cost to replace that was $65 from a dealer in WA + shipping.

That fixed the problem. Several weeks later I get a P0402 (excessive flow).
I checked the EGR valve itself and it checks out fine.
I'm about to test the EGR VSV (vacuum switch valve) that actually turns the EGR system on/off next. The VSV as I recall was ~ $85.
My question is this - if it's not the VSV and my EGR valve checks out O.K. what else could case this code in an SC 300.

I see several posts on the forum from ES 300 fellows, but their EGR system while seemingly similar, is not.

I need to smog my car within the next 30 days so this is an urgent matter.

 

followup on the post above.

I just tested the VSV sitting above and to the side of cylinders 2-3 (the one connected to the throttle body) opens and closes as it should.
Looking at the EGR system diagram, there are other VSVs, which I will have to test as well for proper functioning.
I'm puzzled as to what is causing the P0402 code. Any ideas on resolving the issue are welcome. I have 3 weeks before I'm due for smog.

 

sorry i haven't been on for a while.. Well when i took my lex in, they tested the egr valve and it wasn't that. So they replaced the vsv(vacuum switching valve) and it disappeared. Hope this helps.

 

Thanks Kevin,
There are 4 different VSVs on the EGR diagram on the hood of the 2JZGE.
I've tested the one hooked up directly to the throttle body and it switches on off fine.
Can you point me to which one they swapped for you and possibly a part number ? (even though I suspect 3 of the 4 may have the same part number, while the only different one is the one hooked up to the fuel pressure regulator).
I am a bit puzzled still.

 

After spending $55 at a local Toyota dealer to diagnose my problem, it turned out to be a sticking EGR valve (the most expensive fix from the choices). I'm upset at my mechanic, who told me that the EGR valve checks out fine. Apparently it doesn't. Toyota tech checked the vsv's and modulator,etc.

Got a quote for a new EGR valve part number 25620-46061 at $229.41 and $157 in labor.
I sourced one out at Titus-Will Toyota in Tacoma, WA for $165.56 + shipping and another at Autozone's warehouse in California for $149.99 + tax and free shipping.

Add the EGR valve gasket for $1.50 and the Autozone EGR comes out to $164.73 shipped to me.

I doubt Toyota will be willing to match that price and I'll swap it out myself.
Hopefully this is the end of the P0402.
I'll post again when I have swapped it out and driven it enough to trigger a code if this hasn't fixed it.

 

Update:
after swapping out the EGR valve with a brand new one, the P0402 code came back up about 100 miles later. Luckily I had already passed smog inspection.
Now, with a new EGR modulator and new EGR valve, what else is left there to replace to get rid of this pesky code.
The vehicle runs much better than before. There is no gurgling sound at idle and no hesitation during acceleration.
I cleared the code with an OBDII scanner yesterday and now I am monitoring to see when and if it will pop back up. I have a feeling that it will.
Any other ideas would be appreciated.

The dealership is going to get hell from me, for misleading me into replacing the EGR valve.

 

Code popped back up. 60+ miles later. I notice that it pops up at a particular time and condition, not anytime.
Since I've already reset it a few times, it always comes back under the same conditions: about 1/3 mile down the road after a cold start.
What else could be causing this code, apart from the EGR valve itself and the EGR modulator?
I'm getting sick of looking at the CEL with no fix in sight. If it keeps coming back something is wrong.

 

off topic but kevin are you hmong?

 

is your problem fixed now? What was it?