Hiya Jerry,

Happy Mundae.

How many miles on your 1991 240?

Your hands are too large? I also have ham-handed hands. Didja remove the air intake piping between the air filter box and the throttle body. Should have good access there after. Great time to inspect the accordion like hose for cranks and chafed holes, also.

You received a socket (ignition) fault code of 4-1-3. You repeated the process in socket 6 for any other fault codes? No socket 2 (fuel) fault codes?

Reference our Uncle Art Benstein's current image posting guidance in your brickboard.com posts:



Avoid Photobucket like a plague as I've recommended for many years.

For your Volvo-related images, we have the BrickPix. Press Ctrl + mouse click BrickPix link at the top of this page to open a new tab of the BrickPix page. You only limit is the max one megabyte file size, no matter the image pixel size. Also, use the full URL in the browser address field after you have opened the uploaded image. BrickPix is the same as what Art references as the "Brick Board Gallery" in his bright and happy image you see here. Imgur may be okay for general image sharing.

I also have a 1991 Volvo 240, German Market, grey market import to Yoo Ess Aaaaaay, with EGR.

Image of the EGR temp sensor in the EGR pipe downstream of the valve.

A Volvo TSB relocates the temp sensor to the EGR valve, should you replace the EGR valve, as the EGR valve vacuum diaphragm can fail. (Remove vacuum line, and suck. Comes to a stop and holds? Okay! Or use a vacuum gauge.) EGR valve replacement also requires a replacement of this pipe from the EGR valve out to where it secures at the air intake port manifold.

EGR vacuum servo, sometimes called a pump, As Machine Man Phil mentions, yet is merely a valve opened (energized) by the EZK116 controller when the coolant temperature rises (and closed - de-energized).

You see the cap, and prise up with bladed screw driver. Made of metal. Just don't let it fly away. Hold a hand over it as you prise it up.

EGR Temp Sensor again.


Where the EGR pipe 'downstream' of the EGR valve secures to the air intake port manifold.


As Phil Machine Man says with the EGR controller servo doo-hickey. I agree this may be the cause.

Your temp sensor reads fine for resistance at the two connector pins. Though with multimeter test probes secured to the two connector pins, gently wiggle the wire at the sensor end and the connector end. There is no strain relief for the two wire cable between sensor and connector. 27-28 years of vibration may cause the conductor to break inside the wire. Though quality copper alloy stranded conductor wire is encased in high temperature insulation. The fault is unlikely save for maybe very high mileage EGR equipped 240 with the EGR vapor stream electrical thermistor temp sensor.

You can buy a new replacement. Can you solder? If enough lead remains, solder and seal for underhood conditions.

Else, replace.

Though while not reported, there could be issue with EGR flow as the EGR piping can come clogged as exhaust vapors condensate to clog the piping at the EGR valve and usually downstream of up and at the EGR pipe section where it secures to the air intake port manifold.

Though sort of doubt that as you indicate the single fault code.

If no fault in the sensor wire wiggle test, and a disconnect / connect of the EGR temp sensor after clearing fault socket six fault codes and Phil Machine Man's check of the EGR controller filter material, and the fault continues, than EGR temp sensor may need replacement with new. Or you may have corrosion at the EZK ignition ECU on the fire wall bulkhead at the passenger foot well. Or some other wire route fault. Follow the wires.

Volvo PN 9135404. Rock Auto (81-84$ for two choices), Autozone, Tasca Volvo Parts, FCP Euro have them. Dunno about closer to you iPd. Ebay? Amazon?

Questions?

Hope that helps.

My 1975 Volvo 244 DL in the early or so 1980s.

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