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Model specific boards => Golf mk4 => Topic started by: Sas on 23 August 2009, 21:11

Title: 1.8 20V fuel/boost question?
Post by: Sas on 23 August 2009, 21:11
Alrighty,

Been running super unleaded in the golf since it's remap. It's been quite laggy and eratic when trying to hold boost. Checked all the boost pipes and there's no leaks or kinks.

But.... We were caught out with 0 miles to empty  in the tank and a petrol station at didnt stock super.... so we just stuck in standard unleaded to tide us over. Now, the car has ran perfect all weekend, and holding boost at 17psi no probs, not laggy and didnt seem to be as bad at all! but.... tonight I filled up for going to knockhill tomorrow and managed to fill her with super again and right enough on the way home the bother all started again!!!

Surely this is the wrong way round if the car has been mapped? and we were told to use 98ron once it had the map

any advice would be great ...
Title: Re: 1.8 20V fuel/boost question?
Post by: dubcruiser on 23 August 2009, 21:14
Save your money and stick with normal unleaded!!  :grin:
Title: Re: 1.8 20V fuel/boost question?
Post by: topher on 23 August 2009, 21:22
I'd be surprised if it was the map. Check the condition of your spark plugs, and try going for a drive with the MAF unplugged

also are you using the same petrol station every time? tried vpower?
Title: Re: 1.8 20V fuel/boost question?
Post by: Sas on 23 August 2009, 21:24
it is vpower, i use the same petrol station everytime i fill one of the cars - we both do.
Someone had said it could be the turbo, but that wouldnt explain the difference in the car with different fuels surely?
Title: Re: 1.8 20V fuel/boost question?
Post by: topher on 23 August 2009, 21:30
nah i wouldnt think its the turbo.. try the maf trick first with super in the tank

the higher octane is possibly enough for your maf to spit its dummy.. i had something similar recently when i was experimenting with different maps, 2 broken maf sensors.. one worked with a certain map but the other wouldn't.. and vice versa.