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Alfa Romeo 145 - 146 Forum > Technical > FAQ
During my recent troubleshooting of my fuel pump, I found a way of testing the variator's operation, and the fuel pump operation.

The Variator
I had always wondered if my variator has been operational, it's been rattling since I got the car, and I have a new one at home, but I haven't been bothered fitting it. If you attempt this, you do so at your own risk. Neither me or this website take responsibility for any damage or injury which may occur!

I found that the relay which is most frequently cycled during the normal operation of the engine, is the variator relay by miles. It closes every time you accelerate above idle, opens when you get to around 4000 RPM, and then repeats the cycle as you drop the rev's. This explains why mine looked like it did in the following photo...

To test the operation of the variator, its electro-mechanical solenoid which controls the oil flow to the variator, and the relay itself, you've got to do a simple bit of dismantling. You must firstly locate the variator relay. It's listed in the vehicle handbook as being to the left of the battery under the black dust cover. Remove the dust cover and you should see the following: A relay to the rear of the battery, a fuse block or two, and a relay to the front. The relay to the front is the variator relay. Remove it. To confirm you have the correct relay, start the car with it removed. It should start OK. If not, you have either removed the fuel pump or general ignition services relay. If so, replace it and try another.

If you have correctly removed the variator relay, you now need to open it. With a screwdriver, push out the four tabs on the two sides to allow the internals to slide out from the metal BOSCH shell. Now, look at the device and locate the actuator... the part that 'switches' when the coil gets power. Replace the relay in it's block, and start the engine again. Let it idle for a while until it's stable and running at approx 900RPM or so. Then, push the contact closed for 1.5 seconds or so and release. The solenoid will push the pin to allow the oil to flow into the variator, the variator will shift phase and turn the camshaft 25 degrees, and the engine will stutter and should recover. If you are able to hear the stutter, then you know it's all pretty well functional!

The Fuel Pump
This is quite easy if you have done the variator. Simply move the exposed relay into the position of the fuel pump relay, and with the engine off, close the contacts of the relay. The relay's power is hard wired to the battery, and it will start pumping and making a distinct rushing noise through the injector distribution rail. This confirms the operation of the fuel pump.
Thanks for the very useful testing tips. Had a go on my 146 as it rattles all the time, and was worried it could be something more serious than the Variator! But the test worked and as the switch is engaged the car splutters and the rattle stops for a while but comes back, so im guessing that confirms it is just my variator which need replacing.

Just had the cam belt done 9k ago, but i guess they failed to replace the variator!?

I filmed the test but it won't let me attach it to this post? Is there any type of video formats you can upload? Sorry im a newbie!

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