An OBD2 scan has revealed that my check engine light is being caused by
"Insufficient EGR Flow"
Looking at the suggestion found at
formatting link
i tried pulling themodulator (which I think is the plastic piece that has 1 vacuum tubegoing to the EGR, one out the bottom, and two more out the side goingwho knows where) I tried blowing air into the bottom of the modulator.Air goes through regardless of which one of the upper vacuum holes Icover. I'm guessing its broken.
I've called my favorite parts house, and they can't find anything named
"EGR Modulator Valve" or anything similar. Am I calling this the wrong
Toyota calls that thing an 'EGR vacuum modulator', but you aren't going at it the right way. The modulators themselves rarely fail, and the test you performed tells you nothing of its operation. The normal culprit with the modulator is the small air filter in under the round lid. Pop the top cap off and see if the filter element is melted or clogged. Sometimes it can be blown out and cleaned, sometimes it needs to be replaced. You can't get the filter by itself anymore, but you can cut out a small piece from a fish tank filter and it'll work like a charm. The other usual suspect would be the EGR valve itself. If you have a vacuum pump/gauge you can test it by applying vacuum to the small line going to the top of the valve. If it is clean and operational, it will stall your engine from idle when you do this. But try the filter angle first. If you need a hand post. And you have the same engine as Camrys, so when these people bitch to you about posting in the wrong forum, tell 'em to screw.
I was helping a couple of owners to diagnose EGR problem. One turned out to be the VSV that operates the EGR valve, the other turned out to be dirty throttle body with vacuum ports plugged up. Here were some exchanges from then, see if this helps:
The modulator usually do not go bad, neither does the EGR valve, although it may get blocked by soot.
Throttle body: ============== Air blown into the hoses from the modulator's Ports P and R into the throttle body should flow freely into the throttle body.
To be tested: =============
Test 1 -- To rule out VSV as the problem. Test 2 -- Whether the EGR modulator is indeed the culprit.
Step 1 for VSV:
1A. Disconnect hoses from Port Q at the modulator and at the EGR valve. This leaves VSV with two long hoses to test. Mark them so you can put them back in the right places.
1B. With the engine cold, stopped and ignition ON, Port Q hose leading to the VSV should hold vacuum, use about 15". And blowing through the EGR valve end of the hose you will hear air coming out of the VSV filter, which will help you locate it as well.
1C. With the engine warm and at 2500 rpm, Port Q end of the hose should loose its vacuum automatically as VSV is opened. This means the Port Q hose now opens all the way to the EGR valve end of the hose.
This confirms VSV and its control circuit is working; otherwise the VSV or the vacuum hoses leading VSV to are leaking or VSV is not energized. Verify proper electrical connection to VSV. Clean or change the VSV and hoses.
Step 2 for VSV while also checking out modulator:
2A. Now your engine is warm in diagnostics mode from Method 1, tee Port R of the modulator to the MAP hose (getting full engine vacuum now).
2B. At 2500 rpm, you should measure about 13" at Port Q of the modulator.
If the numbers are the same at Port Q of the modulator and at the EGR end of the hose, then VSV is working.
But if Port Q of the modulator shows a higher vacuum than at the EGR valve, then the VSV or the vacuum hoses leading to VSV are leaking. Clean or change the VSV and hoses. In this case of higher vacuum at Port Q, a direct hose from Port Q to the EGR valve should cause the engine to run rough in the diagnostics mode at 2500 rpm. If not, you may have problems at both VSV and modulator.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.