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Pissed'n'broke
Wednesday 10th May 2006, 13:25
Hi there

I have a problem with my V70R in that the engine seems to drop the revs when the car is idling AND whilst driving. The problem is intermitent, which is always a pain when trying to resolve.
I have put Optimax into the tank and it stops the problem. It also feels slightly faster!!
Every time I change back to a lesser fuel the problem reoccurs. Should I just stick to Optimax?

Has anyone else had this problem?
Can you tell me the cause and correct remedy?

By the way. Optimax on Bath Row in Birmingham is £1.02 per litre at the moment.

t5owner
Wednesday 10th May 2006, 13:35
That`ll be the poor engine management trying to adjust itself for the crapper fuel you put in if your gonna use cheapo fuel i would suggest a full tank and then disconnect your battery for 24 hours to allow the ECU to dumb down and then when you reconnect the ECU will learn the settings for the new fuel and adjust everything itself this should stop the erratic revs

Otherwise as you say stick with the optimax as our engines prefer and volvo reccomend higher octane fuel for best performance

Cheers

stuart

blackbooty
Wednesday 10th May 2006, 13:38
Hi there

I have a problem with my V70R in that the engine seems to drop the revs when the car is idling AND whilst driving. The problem is intermitent, which is always a pain when trying to resolve.
I have put Optimax into the tank and it stops the problem. It also feels slightly faster!!
Every time I change back to a lesser fuel the problem reoccurs. Should I just stick to Optimax?

Has anyone else had this problem?
Can you tell me the cause and correct remedy?

By the way. Optimax on Bath Row in Birmingham is £1.02 per litre at the moment.

cant help with your prob but heres a suggestion....
i always used opti until i tried out tesco 99, car runs lovely, is quicker and 5p a litre cheaper than opti.

Pissed'n'broke
Wednesday 10th May 2006, 13:44
thanks for that

by the way. how do you disconnect the ECU?

the last time i tried to fill up at tescos they only had 97 ron. Does anyone know where you can get the 99 stuff from.

cheers

t5owner
Wednesday 10th May 2006, 13:58
thanks for that

by the way. how do you disconnect the ECU?

the last time i tried to fill up at tescos they only had 97 ron. Does anyone know where you can get the 99 stuff from.

cheers

Don`t need to disconnect the ECU itself unless you want to easiest way is to disconnect the battery for 24 hours as the ECU will dumb down to default settings after its been starved of power and then it will reconfigure its self to the new petrol when you reconnect the battery and have a say 20 minute drive

Cheers

stuart

blackbooty
Wednesday 10th May 2006, 14:37
not sure on that one mate, i was under the impression it was available at all tescos.

jeleebaby
Saturday 13th May 2006, 21:58
I think that tescos have replaced the 4 star pump with 97 Super unleaded. Only some stores have the 99 Super unleaded

pzorb
Saturday 13th May 2006, 22:05
I've never understood this. VT say that if a car is mapped to n octane, then putting more octane in will make no difference power-wise (maybe better mpg etc).
Yet there's often talk of the car readjusting itself to cope with different types of fuel, like running it on 98 for a month then switching to 95 will somehow trigger something to readjust?
They can't both be true, because they're opposite :confused: Or have I misunderstood something?

T5ER
Saturday 13th May 2006, 22:07
put it on a diag and see what pops up but as said if you have the RICA 304 chip apparently you have to run 97 octane upwards,but check with ADAM or Hamish to confirm

pzorb
Wednesday 17th May 2006, 18:22
Any update? :)

Engineer
Wednesday 17th May 2006, 18:44
I've never understood this. VT say that if a car is mapped to n octane, then putting more octane in will make no difference power-wise (maybe better mpg etc).
Yet there's often talk of the car readjusting itself to cope with different types of fuel, like running it on 98 for a month then switching to 95 will somehow trigger something to readjust?
They can't both be true, because they're opposite :confused: Or have I misunderstood something?

Its an ethanol thing Mart 5% seems to be the norm, loads of info on the internet and various threads/posts here and other sites discussing this subject some for some against as the case may be.