Hello all. I have a silght problem with my 1980 Volvo 240 DL B21F k jetronic fuel injection. The damn thing won't start when it's cold. I've just replaced the air bok, pipe above the air box, cold start injector, and i just got done replacing the warm up regulator. All the parts are new from my local Volvo dealer. I've had a mechanic who's good with Volvos look at it and he told me do replace the warmup regulator. so Please help me befor I do kill my volvo by shooting it with a 12 gauage Shot gun.
Thank you all,
Ian Schilf
ischilf@yahoo.com

If it won't start "Period" when it is cold , I would look at the cold start injector, wiring and thermal cutout switch. I usually check the injector first by unplugging it and routing a hot wire and ground from the battery to the injector. Ground one terminal on the injector and "touch" the other terminal with the hot wire. The relay should click. If it doesn't, replace the injector.
If it does, connect a test light across the wiring harness connection and try to crank the car. If the light shows current flow, then the problem is not with the cold start injector circuit. If it doesn't, you either have a bad thermal switch or a bad wiring connection. The thermal switch limits the amount of time that the injector can fire (about 5 seconds). This prevents flooding the engine with gasoline. If it goes bad the injector will not work at all.
If it is only hard to start when cold, I would check for residual gas pressure when the engine has been shut off for a few hours. There is a spring loaded gas accumulator mounted beside the fuel pump that maintains a standing gas pressure on the injection system. This allows the fuel pump to pressurize the system rapidly during starting. If this pressure leaks down during shutdown, it causes hard starting. If the leak is slow, the car will start fine after the first start, and any following starts until you let it sit for a while and the gas pressure leaks down. Possible sources for the leak includes the cold start injector, any of the (4) fuel injectors, the check valve at the fuel pump discharge or the fuel distributor. The leak will be into the tank return line and is not visible.

No need to start shooting, this is most likely a very simple thing and of electrical nature. Typically these symptons are related to the start injector fitted on the earlier models.

As per other comments, check for voltage on the injector (lightbulb) it should go on during cold start only. If nothing happens, you will find the connector on the cold start relay has a broken wire. The regulator is fitter at the back driver side of the engine, near the heater hoses. It is screwed into the block like the temperature sensor. It has three wires going to it, two are for the switch, one is power for heating it up. The switch is basic reed type that switches off when warm.

It's a pig to get to, but you can follow the wire from the cold start injector and unplug the plug to check wiring/voltage. Repair costs a few cents.

Work fine on an 84 B23E I owned, knocked about $500 of the price for the fault, fixed it in half an hour.

Good luck,

Jorn

It doesn't start at all, or it's difficult? What's your temperatures like?

One easy thing to do would be to check if the cold start injector is getting voltage at startup. Use a test lamp and have someone crank the engine while you check. Use caution, the engine may start while you are doing this.

Which part did you replace when you say the "warm up regulator"? The thermostat valve (on the head), or the control pressure regulator (on the block)?

Greg

I'd shoot it, OO magnum load. Stand back and wear safety glasses. Gets boring real fast though. Then soak the whole thing with kerosene, two gallons. That's the real fun. "Love affair", over, and real pleasant memories.