Vectra conks out - ECU error code 0100

The symptoms you describe are typical of an engine that requires a new idle air control valve, and to have the throttle valve reset to give a higher base idle setting. This is an involved job, and requires use of a diagnostic computer to interface with the vehicle ECU and monitor engine parameters while the throttle is being reset. An oil trap is also installed in one of the crankcase breather pipes to prevent contamination of the new idle air control valve.

As a temporary measure, the idle valve and throttle body could be cleaned out with carburettor cleaner, although if it does make a difference, it will only be temporary.

When I last carried out this modification, a new idle valve was £140+VAT from Vauxhall. Labour was 1 hour, and about £20 for other parts such as gaskets and the oil trap.

HTH

Anthony Remove eight from email to reply.

Thanks for your reply. Someone on the Vectra-Sport forums has suggested that I get one from a scrap yard incase the wiring is faulty.

Also, are the MAF sensor and "idle air control valve" the same thing?

--Nick.

Nick wrote on Mon, 03 Jan 2005 20:58:34 +0000:

Er, just one, rather obvious idea. Try actually replacing the MAF sensor?

Depending on the type, new air-flow sensors aren't massively expensive and it's possible you may not have to go to a main dealer to get one (the local parts factor near me stocks coolant temperature sensors for engine-management systems). As you've already located it then you'll have a good idea what you need to do to remove and refit it. I wouldn't have thought that the RAC would do this for you, and you've probably already worked out that you don't need the dealer to be involved at this stage.

There has been mention of the idle-speed control valve; this is a possibility but almost certainly would be a dealer-only part so it'd be worth replacing the MAF first to see if that cures it, especially as that's what the ECU is reporting (and let's face it - is the first thing the dealer would replace after hooking up their diagnostic tester)...

Final thought: have you checked for air leaks between the sensor and the engine itself? A split pipe or blowing (sucking?) gasket will allow a different amount of air into the engine to what the sensor is reporting and that could fool the ECU into thinking it was a sensor fault...?

Darren

I haven't checked anything yes - I'll have a look at the area around the MAF sensor today and then have a look to see if I can see anything wrong.

I'll report back tonight or tomorrow.

--Nick.

Good suggestion, the rubber hose connecting the MAF to throttle body was badly split on the wife's Vectra when we bought it (not that I knew how it drove as it had shed it's timing belt!). A new replacement from Vauxhall was about 5 quid. New MAFs are around 150 I think, tune-parts may sell them cheaper.

Be worth spending a few minutes talking to a breakers yard, got an ICV from there (previous posts here have introduced this as a possibility) for a few quid; probably only cost a couple of extra quid to bundle that with the air pipe (with MAF embedded if this is DIY dismantling) - waved in front of the face of the breakers they shouldn't charge much.

FWIW, if it is an ICV (easily checked with £5 can of carb. cleaner), and you want a new replacement, don't just try Vauxhall, try some independent motor factors - picked one up for a Ford Ka for a very reasonable £70.