why does my alpha 156 lack power/acceleration, I have put in fuel cleaner etc?

Answer 1

Hi

We need to know which engine is in your 156. For the purposes of this question I am going to assume it is the Twin Spark engine.

Disconnect the wiring plug from the MAF sensor (located at the air filter housing). If the Alfa then runs any better then you have a faulty MAF.

Your next check is the VVT actuator which I believe to be on the left hand side of the cylinder head on the end of the inlet camshaft.

Pull the rubber boot away from the actuator and disconnect the two wires from it and then start and drive the vehicle. If it runs worse then reconnect the actuator, but if it runs no differently then read on:-

With the engine idling, check the wires of the actuator for battery voltage. There should be NO VOLTAGE at idle.

Next, raise the revs to over 1200 rpm and check for voltage again. There should be battery voltage at one of the wires at speeds of over 1200 rpm.

If not then there may be a problem with the VVT actuator relay or its wiring.

If there is voltage then with the engine at idle, apply battery voltage to the live terminal of the actuator. The engine should either run rough or cut out.

If it idles normally with voltage applied then the actuator is at fault.

Apart from the above you could have a faulty coolant sensor, low fuel pressure due a weak pump, blocked fuel filter, or faulty pressure regulator, and a few other different things, but the above will do for starters.

Cheers

Geordie

Answer 2

The main reason your Alfa 156 could be lacking power is the air mass meter located between the air filter housing & the throttle body housing, disconnect it, if it makes no differences then this is more than likely the problem, the wires going to this sensor can also break, so check inside the protective boot, its worth checking first. The coolant temp switch can also give trouble.

Answer 3

You forgot to buy a Honda!