Hello,

This is my first post on here so please go easy on me. I was just wondering if anyone with greater knowledge than I could shed some light on my problem.

I have a Fabia 2001 1.4 classic, and the Engine Management light is always on, I had it checked out at my local garage and their diagnostics came up with

Fault Code: P1640, fault location: Engine Control Module - defective

They are reluctant to proceed and suggest taking it to the Skoda Dealer, but I do have concerns over their abilty to solve the issue as I have read many of the previous threads on very similar problems.

The car has been MOTd and Serviced with the light on and runs perfectly so I am not too concerned but would obviously like to find the cause.

So if anyone could share their opinion or expertise on this I would greatly appreciate it.

Eddie

I found this - 18048/P1640/005696 - Ross-Tech Wiki

Possible Causes

Engine Control Module modified (e.g. Chip Tuning)

Engine Control Module faulty

Possible Solutions

Contact your Tuner

Replace Engine Control Module

Thanks for that,

Do you have any idea how much it would be to replace the module? and does it need to be done immediately?

Depends on the model etc of your car but there is a similar thread running at the moment and somone has paid around £700 IIRC.

They are not cheap and if you haven't got your immobiliser code can really only be done by a dealer. If you got a used one you will need the immobiliser code for that as well.

Thanks again for your comments,

Doesn't sound too great, but does it have to be done or can I just run the car with the light on? What exactly does the module do? (sorry I'm a bit of a novice)

It basically controls the engine, how much fuel to inject into each cylinder and when, when to produce the spark to ignite the fuel.

To be honest if I was looking at that sort of repair bill and the engine was running well and the emissions were upto MOT requirements, I would be inclined to leave it. Whatever you spend on it will not add to the cars value. A cheaper option that any garage could do would be to fit an Engine Control Unit, a dash panel and a lock set with keys all from the same donor vehicle (this is so that all the immobiliser data tallys up), though the mileage reading won't.

At present it is OK, it could stay that way or get worse, poor starting, cutting out and general running problems. If any of thses crop up in the future any garage would want to replace the control unit first before they will even consider finding the cause of the new problem.

No reason why you cant use a second hand engine ecu and code it to your car. The chassis info from the other car will still be on it but it will write yours next to it.

Thanks again for your comments,

I did do a quick search online and a company called auto tek electronics have offered to "supply, test and recondition" my module for £39.99 but they need a part number before proceeding.

Do you guys know the part number, and do you think this is a wise idea?

It seems a bit to cheap to be true. Whenever we have taken that route at work they usually report to say no faults were found, that'll be £XX please. It depends on whether (in my opinion) that you are willing to gamble £39.99.

If you look under the bonnet, the ECU (a silver box with 2 quite laege electrical plugs) is clipped to the bulk head on the passenger side, it will have a label on it with a part number. This may well begin 047.