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TrevHelpsYou, Mechanic
Category: Car
Satisfied Customers: 74
Experience:  10 Years Salvage
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1997 Toyota Camry: the check engine light comes..EGR valve..cleaner

Customer Question

1997 Toyota Camry, sometimes the check engine light comes on and stays on for 3 or 4 days then will go off and stay like that for 3 or 4 days as well. I had Auto Zone check the code for free and it flags the EGR system as the problem. A friend said to remove the EGR valve and clean it with berry-mans cleaner and reinstall it as it could just be dirty and sticking form time to time. What is your advice ?
Submitted: 9 years ago.
Category: Car
Expert:  TrevHelpsYou replied 9 years ago.
Hi, Trevor here.

Can you tell me what motor you have? It should be under the hood on a sticker with the belt diagram on it if you do not know. Some EGR valves and systems do not handle being cleaned like the older models. I always suggest replacing them. Cleaning I feel is always temporary.

Please let me know and I will prepare some instructions for testing and replacing your EGR system.
Customer: replied 9 years ago.
It is a 4 cylinder 5S-FE
Expert:  TrevHelpsYou replied 9 years ago.
Ok below you will see tests for the system and removal and replacement instructions.

5S-FE Engine

1. Check and clean the filter in the EGR vacuum modulator. Use compressed air (if possible) to blow the dirt out of the filters and check the filters for contamination or damage.
2. Using a tee (3-way connector), connect a vacuum gauge to the hose between the EGR valve and the vacuum modulator.

Exhaust Gas Recirculation (EGR) system components—5S-FE engine

3. Check the seating of the EGR valve by starting the engine and seeing that it runs at a smooth idle. If the valve is not completely closed, the idle will be rough.

The check connector is located near the air cleaner.

4. Connect terminals TE1 and E1 in the check connector.
5. Inspect VSV and EGR vacuum modulator operation with hot engine. With the engine coolant temperature above 140°F (60°C) on AT and 131°F (55°C) on MT, check the vacuum gauge and confirm 0 vacuum at 2500 rpm.
6. Warm the engine up and check that the vacuum gauge indicates low vacuum at 2500 rpm.
7. Disconnect the hose from port R of the EGR vacuum modulator and connect port R directly to the intake manifold with another hose. Check the vacuum and make sure the reading is high at 2500 rpm.

Port R is the lower of the two ports. As a large amount of exhaust gas enters, the engine will misfire slightly at this time.

8. Disconnect the vacuum gauge, SST or jumper wire and reconnect the vacuum hoses to their proper locations.
9. Check the EGR valve by applying vacuum directly to the valve with the engine at idle. (This may be accomplished either by bridging vacuum directly from the intake manifold or by using a hand-held vacuum pump.) The engine should falter and die as the full load of recalculated gasses enters the engine.
10. Remove the jumper from the check connector.
11. If no problem is found with this inspection, the system is OK; otherwise inspect each part.


1. Remove the EGR valve.
2. Check the valve for sticking and heavy carbon deposits. If a problem is found, replace the valve.
3. Reinstall the EGR valve with a new gasket.


1. Label and disconnect the vacuum hoses from ports P, Q, and R of the EGR vacuum modulator.
2. Plug the P and R ports with your fingers.

Blow air into port Q and check that the air passes freely through filter of the vacuum modulator

3. Blow air into port Q. Check that the air passes freely through the sides of the air filter.
4. Start the engine and maintain 2500 rpm.

Repeat the test with the engine running at 2500 rpm. Air should not pass through the filter

5. Repeat the test above. Check that there is a strong resistance to air flow.
6. Reconnect the vacuum hoses to the proper locations.


1. Check that air flows from port E to port G.
Check that air flows from port E to port G of the VSV

2. Connect the vacuum switching valve terminals to the battery.

Apply battery voltage across the terminals of the VSV

3. Check that air flows from port E to the filter.
4. If the VSV fails this test replace it. Any doubts perform the following test.
5. Remove the VSV.
6. Check for an open circuit. Using an ohmmeter, measure the resistance (ohms) between the two terminals of the valve. The resistance (cold) should be 33–39 ohms. If the resistance is not within specifications, replace the VSV.

Check for an open circuit in the VSV using an ohmmeter

7. Check for a short circuit within the valve. Using an ohmmeter, check that there is no continuity between the terminals and the VSV body. If there is continuity, replace the VSV.

An ohmmeter can be used to checked for a shorted VSV also
EGR Valve

  1. Disconnect the negative battery cable.
  2. Remove the air cleaner hose and lid. Disconnect the IAT sensor wiring.
  3. Disconnect the accelerator cable bracket from the throttle body.
  4. Remove the throttle body from the air intake chamber.
  5. Unbolt and remove the engine hanger, air intake chamber stay and EGR vacuum modulator. Discard the vacuum modulator gasket.
  6. Loosen the union nut of the EGR valve. Disconnect and label the hoses attached to the valve.
  7. Disconnect the EGR gas temperature sensor wiring.
Click image to see an enlarged viewPrior to EGR valve removal, label all hoses for the EGR valve (1) and vacuum modulator (2)
  1. Remove the nuts, EGR valve and pipe. Discard the gaskets.
Click image to see an enlarged viewRemove these three nuts to separate the EGR and modulator from the intake manifold
Click image to see an enlarged viewPull the unit from the engine . . .
Click image to see an enlarged view. . . and discard the old gasket

To install:

  1. Place a new gasket on the cylinder head facing the protrusion downward. Install another gasket on the EGR valve and pipe and secure with the mounting nuts. Tighten them to 9 ft. lbs. (13 Nm).
  2. Connect the EGR gas temperature sensor wiring.
  3. Attach the vacuum hoses to the valve in their proper locations.
  4. Tighten the union nut on the EGR valve to 43 ft. lbs. (59 Nm).
  5. Install the air intake chamber stay, vacuum modulator and engine hanger. Place a new gasket into position facing the protrusion downward. Tighten the assembly down with the bolt and attach the hoses.
  6. Install the throttle body with a new gasket. Attach all wiring and hoses removed.
  7. Connect the accelerator cable bracket to the throttle body.
  8. Install the air cleaner and hose. Attach the IAT sensor connection.
  9. Attach the negative battery cable.
Hope this helps. If so please click accept. If not then please let me know and I will try to help.
Expert:  TrevHelpsYou replied 9 years ago.
YOu will see the removal instructions below. I imagien you get or got a code like a

P0401 EGR Flow Insufficient.
P0402 EGR Flow Excessive.

I suspect 402 as it is stuck open from getting gunk in it.
Customer: replied 9 years ago.
It must have been code PO401 as I remember the print out saying EGR Flow Insufficient. Is the procedure you suggested the same for this code also ?
Expert:  TrevHelpsYou replied 9 years ago.
Yes I gave you full testing for the system. And it is best to test before replacing any part. The after market parts are cheaper but they can be spendy still. The newer EGR valve parts are a little more involved then teh old ones you could flush out and reuse for a long time.

an example of OEM parts is below just ot give you an idea
But the tests I gave you are not hard to do. Also if you need some help with instructions for the volt/ohm meter just let me know and i will get some for you.