Zafira-engine cooling problem

Curlywurli

Typical whenever we get any savings something goes wrong! Whenever I drive the car the engine cooling light lights up. The manual says I can drive it. We've just had it serviced today and they can't find what's wrong with it. We've now got it booked in to the Vauxhall dealership and they are going to do a £50 test on it.
Sometimes when I've turned the engine off I can hear the fan still running and it only stops when I put the key back in the ignition and turn the engine on and off again and it's also eating up petrol (same journey- another third of petrol). I don't suppose anyone has any idea what could be wrong with it or how much it roughly might cost. I just don't want to be conned. Last time we took it to the dealership they charged us £400 for an exhaust which we later found out they had not fitted correctly! Thanks for any info.

Pssst

Maybe there is a temp sensor somewhere which is faulty and therefore telling the EMU that the engine is cold when its actually up to temp?

This might explain the fuel consumption as the mixture will be being constantly enriched (for cold running-warm up) even when the engine is warm.

Another sensor will be calling the fan to run to cool down the warm engine when you stop driving/turn off ignition.

The two conflicting messages lay well be generating the fault light as the EMU will be wondering why the fan is running when the other sensor is saying > engine cool>enrich mixture for cold start /warm up.

Just my theory.

Sirbendy

First thing: what age Zaf?

Second, which light comes on? They're based on the Astra, so is it the engine block, the "spanner" or the radiator with a "*" in it?

I know if I get the engine block lamp (and it MAY apply to the others, in fairness I've not seen them light up yet), I can read the faults on mine by turning the car off, then putting my foot flat on the throttle and the brake at the same time, then turning the ignition to "II", without starting. Once the initial self test has finished, one of them..might be the spanner, can't recall..will flash out a sequence.

10=0, other amounts = numbers, so 10,4,10,10 would be 0400. This you can reference online to find possible faults using https://www.topbuzz.co.uk.

This IS accurate, as I had a 0400 error on mine, confirmed when I bought a copy of the vauxhall diag system from eBay and plugged it in linked up to my laptop..a 0400 is an EGR failure.

Only hitch is I think they wrote this "backdoor test" out of the system in 2001ish, or so I've heard. Might be worth a shot regardless.

Don't feel you have to go to Vx for the readout..any garage with the Tech2 or equivalent kit can do it. My "home" kit cost me a grand total of £40 and allows me to do everything from reading errors to clearing them and testing all the sensors etc, as well as logging the data as I drive for review. It was well worth it. I can program keys with it as well it seems..not tried yet.

When I contacted Vx about my error, they said "you need to bring it in for diagnostics". When I said "Actually, I can do this..", the guy admitted he'd never heard of it. Heh. I love finding out little tricks like that.

I did see a cooling error on mine yesterday..I got a "sensor range error"..no warning light though. That said, I literally just had the belt/thermosta/water pump replaced today, and apparently my pump was piddling water..that might explain it.

Rolandtheroadie

Pre 2000 vauxhalls can be diagnosed with a paperclip as well.

Sirbendy

very true..not all can though. I had a 97 astra auto before that wouldn't yield to it. It was missing a pin from the diag link.

mikey72

Depending on the engine, there are two or maybe three coolant sensors.
The fault code can usually be read by either on the methods above, dependant on the age of the car.
Try the test and post up the fault code, check it a couple of times, it's hard to count first time round.
Same light can come on with an air con fault as well.