High revs no power

[mehlolo1979]

I have a 2000 Bora V5 engine code AGZ.Recently during this cold winter months it has developed some problem as follows; I have to start it in the morning and let it idle for some minutes or it will just be revving above 3000rpm with the engine taking quite some time to reach at least 50km/h once i get on the motorway.The gear changes are also erratic especially gear 3 and the heating system only barely blows out warm air.Took it to have some faults diagnosed yesterday and the mechanic cleared the errors which had been shown by the diagnostics though i did not get the error codes.He then told me that sometimes the ECU can throw up some errors due to some bugs in the unit needless to say the car was okay for the rest of the day but this morning it did the same thing again.I should point out that it only does this when its cold or when it's been standing for more than 8 hrs.Help will be appreciated

[zollaf]

what temperature is it reaching as indicated by the gauge ?

[mehlolo1979]

Thanks for the reply

The temperature goes to 90 and stays there but this morning i also noticed that the fuel consumption has risen considerably

[zollaf]

get the computer on it with the engine hot and look at the temperatures. i think you will find the coolant sender has failed and telling the ecu its a lot cooler than it is.

[mehlolo1979]

Appreciate the reply.

Maybe i should mention that the diagnostics was done with the engine not running just the ignition on so you suggesting that i have it done again with the engine running this time right?By the way the initial errors which came up with first diagnosis were as follows;

1.Engine electronics - fault
2. Transmission - fault
Air con/Heating - fault

Could this faults in any way be resulting from a failed coolant temperature sensor

[zollaf]

yes, run the engine with the computer connected and looking at the live readings. the coolant temp should be around 87-92 degrees.

[mikeybutch]

High revs and no speed is clutch slipping

[mehlolo1979]

Yes it is but only when it shifts into 3rd

[mikeybutch]

You will notice it more in higher gear mostly when going uphill.It will get worse quickly and can suddenly fail completely.Just happened on my wifes Bora and the plate cracked from side to side

[mehlolo1979]

By plate i take it you mean the clutch will i have to replace the dmf as well coz that seems to be the general consensus in these forums