Bugeye Fuel Knock Sensor problem. 15MPG!
 

Hello guys. The engine light had been appearing on the dash intermittently so i took it to the local mechanic diagnosed it with the hand-held device and said something like its the fuel-knock sensor.

I recall having a similar issue about 18months ago when a different mechanic cleaned out the "butterfly valve"

The car drives fine without any noises, jerking or problems but it is burning fuel like crazy. Only does around 180miles on a full tank (urban and motorway miles with careful driving as well).

The mechanic said he might have to take out the whole fuel-knock-butterfly section (i forget the exact teminology) and clean it properly and see if that resolves the issue.

Has anyone had any similar problems before? What aspects of the car could lead to it burning way more petrol than it should? Any links to any other info or websites would be much appreciated. Thanks

Mechanic doesn't know his arsehole from his elbow. Never heard such tripe,

The knock sensor is located in the engine block and cannot be cleaned its a simple single bolt fixing. And a multiplug. I'd suggest changing this if that's the code you've been presented with as the vehicle will be limp home mode.

Knackered lambda sensor...

dunx

You got any other symptoms?
A faulty knock sensor will really kill MPG as the Fine Knock Leaning sporadically retards and advances the timing due to random signals from the dodgy sensor. The knock sensor can fail with no warning or even a CEL. IIRC knock sensors have about a 10 year life span so that would be about right with your bugeye.
I recently replaced the one on my bugeye and its back to normal now.

The only syptoms I had were random hesitation and poor MPG. Only way i realised it was possibly faulty was that on a diagnostic run it showed pulled timing.

Unfortunately the bugeye knock sensor is about the most expensive one you can buy but Import Car Parts will do you one for about £80 delivered :thumb:

Thanks for the response guys. £80 is a small price to pay compared to the fuel i have been buying. I might have had this problem for a while but only just realised it.

Yeah, the symptoms creep up on you slowly until you realise there is a problem. My knock sensor didnt show up faulty on the diagnostic run, the only clue was the retarded timing.

I found the link where I got mine for you: http://www.importcarparts.co.uk/part...knock%20sensor

Looks like its down in price slightly which is good :thumb:

Figured i had better give an update (for others with similar issues).

It was the knock sensor. Purchased it from importcarparts.co.uk for around £70. Local Mechanic fitted it for free - as it took him less than 5mins. Problem Solved. MPG now looks like what it is supposed to!