For almost a year, my 240 has been dying when at a stop light/sign. Since this has begun, I've replaced the fuel tank, fuel sending unit w/filter, some of the fuel lines, fuel relay, and just replaced the crank position sensor. The check engine light is on and hasn't turned off since. Any one else experience this and could help with a solution? Thanks for your time!

 

Have you read the codes triggering the check engine light? What are they?

 

Have you cleaned the throttle housing, set the basic idle and made sure your idle motor/iac/auto air valve/whatever you want to call it works?

And also as others have asked - what codes do you have stored?

 

I am not familiar with how to get the code/s for this car. And no I have not cleaned the throttle housing. Any guidance would be much appreciated. Thanks

 

The pcv system dumps oil fumes (crankcase) into the plastic pipe before the throttle plate - those condense and form deposits where the plate closes and reduce the volume of air - that the engine relies on to idle. More air = higher idle, less air =car stalls. I would suspect the idle motor does not work correctly at this time - that's ok - you can adjust around it. Older cars/Volvos did not have a automatic idle valve - they relied on the throttle plate setting and /or a separate air bleed valve that was easier to adjust. Buy a can of carb cleaner and clean the inside of the throttle housing - it's easier with it off the car (3 nuts) but you should replace the throttle housing gasket if you take it off. Many times carb cleaner sprayed in the housing and on a wiping rag does a good enough job. Just make sure it is completely clean - aluminum is silver and carbon is black.

This website should be helpful for code/self diagnostic info.

https://www.volvoclub.org.uk/faq/EngineOBDCodes.html

 

i should be getting my gasket in the mail today (09/03/2021) and I'll clean the throttle housing over the weekend. And I'll let you know the outcome. Still haven't figured out how to read the codes, but I haven't given up and am still trying. Thanks for your help

 

Copied from above link, it's really quite a usefull tool and the first thing you should check if you have running problems. You can read most codes with the engine running, and read further in the link for erasure instructions.


1. Diagnostic Test Mode 1: Fault Code Retrieval

• Place the cable into socket 2 (LH2.4/Regina/Motronic 1.8fuel injection test) or 6 (EZK116 or REX1 ignition test) as above
• Turn the ignition ON to KPII without starting the engine
• Select Mode 1 by pressing the button once and holding for more than 1 second but less than 3 seconds
• The LED lamp will flash in successive series of three digits followed by a three-second pause. If there are no fault codes stored, it will flash 1-1-1 indicating the fuel injection system is operating correctly. (If nothing flashes, see No Code.)
• Count the successive flashes and record the fault code.
• Press the button again.
• Record the fault code. If it is the same as the previous one, then no additional codes are stored. Repeat until all the codes stored are retrieved (maximum of three.)
• Refer to Table 1 for the interpretation of fault codes from the LH2.4 Fuel injection System and Table 2 for codes from the EZK 116 Ignition System.
• Move the cable into socket 6 (for ignition codes from EZK116 or REX1) or socket 2 (for fuel injection codes from LH2.4/Regina) and repeat the above.

NO Code?Can't Obtain an OBD Code? Malfunctioning OBD Code Reader?

[Inquiry] I tried obtaining a fuel injection diagnostic code and can't even get 1-1-1.

[Response: Chris Herbst] I have run into a LOT of Volvo products with bad diagnostic readout units, usually caused by corrosion. While it is possible that there is no signal TO the diagnostic unit, it is just as likely that either the connection in the terminal, or the connection TO the unit from the ECU computer, is bad. You should try cleaning those connections, and if necessary you can jiggle the connections until you DO get proper readings. I've never had it where I wasn't able to at least read codes and reset the computer, although sometimes it was when I was squeezing the connections into the diagnostic readout unit, or jiggling them around. While your problem could be the ECU, more likely it is corrosion or a bad connection, especially if the engine is operable. [Chris Mullet] When I could not get the LED to illuminate, it turned out that the LED itself was burned out. I picked up another one off a wrecked car and it got me back into business.

If you have an ohm meter to test continuity, you can pop the unit open and check out the LED, resistor, button contact, etc. Be careful as there are a couple tiny springs that can go flying when you open it up. [Doug Bennett] Remove the unit from the fender wall. The there is a plastic cover that covers the button. There are two small tabs, facing inward. Depress these with a small screwdriver, and carefully swivel the plastic cover away. The button will now come out. BE CAREFUL NOT TO LOSE/DROP THE TWO SMALL SPRINGS ON EACH LEG OF THE BUTTON! Luckily, I had a magnet handy. On both the bottom of the button and down in the test unit itself, are the contacts. Mine were filthy. 15 seconds with a Dremel, reassemble, and all is well!

 

Hoonk, cleaning the throttle body did not help. And what did you mean by "set the basic idle"? Since I cleaned the throttle body, the car seems to be idling a little high. The engine started revving up and down while idling. Are these issues connected and any idea why the motor would be revving up and down? Thanks for your time.

 

I have only worked on older Volvos that have no scanners so I will suggest what to look for on trial and error basis and are simple to perform.

When you clean the throttle body you should check the throttle position sensor. It has a micro switch that clicks when the throttle plate is released to close. Adjust it so you hear that click.

To check your MAF sensor or AMM, with the engine running on idle, pull out the plug. The engine should cut out and stop if the sensor is working properly. If engine continues to run after pulling out the plug, the sensor is dirty or faulty. Get some CRC MAF sensor spray cleaner and shoot it through the tunnel. Try again.

I would also check the fuel pressure regulator. With engine running, just pull out the rubber hose. If fuel drips out, the regulator is faulty. Replace it.

The IAC valve was already mentioned but this does not affect the engine as much as the previous items. Hope this helps!

 

On a," Haynes or Chilton book,they show you the," old school diagnostic reader on the driver's side,and how to use it,and basic things like," MaF,etc.. as the "240" were pre- OBD 1 or 2.very basic& very easy too..