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Al115
Monday 9th May 2005, 17:35
Here's a poser for all you Volvo-heads out there...

My T5 fuels beautifully up to ~5000rpm, and then *suddenly* runs massively lean and starts to detonate. It's like someone's flicked a switch!

I have swapped (and thus can discount) the injectors, and have recently replaced the intake air temp sensor and the MAF. We've even tried a new ECU map and we get the same effect, at the same rpm, but with different boost levels. And I checked the fuel pressure about six months ago, when it was fine, so the pump *might* have failed since, but it seems less likely.

Can anyone suggest the likely culprit(s)? So far I've got on my list - boost control solenoid (replacement from main dealer: £38 + VAT) - boost pressure sensor (replacement: £63 + VAT) - fuel pump (replacement: £260 + VAT)...


Alastair