Back fire problem

KJT said:

I have a 4.6 1999 autobiography. I am getting a backfire though when i drive it from cold. once driven a mile or two it seems ok. What could be typically causing this?

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Asuming you mean the vehicle and not yerself personally getting the backfire I'd say unburnt fuel in yer exhaust is normally the culprit

Great, so how do you solve that?

KJT said:

Great, so how do you solve that?

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Buggered if I know I've got a TD5 Defender. You just asked what would cause it.

Is yer timing out, do you have knackered plugs, leads ?
You said in another post yer havin trouble gettin it to accelerate above 4000 rpm sounds to me like there's a connection there somewhere.

Yeah probably is. Think it's time for a tune up.....

try warming it up and unplug the maf senser..

what on earth is that? and why?

KJT:

The miss could be a number of things... Check you plugs, leads first.

The MAF is the Air flow meter -give the ECU info about the air gussing down the air intake. Sits just after the Air filter box and hsould have a multi plug on its right hand side (looking from front to back). Unlplug this and go for a spin. If no difference then this may be your problom. Logic here is that if somthing that should make a difference is unplugged and doesn't - then it be fu**ed.

The 4K rev limit may be the MAF aswell plus check that the Air box is clear and flter isn't blocked.

You could always try spaying a can of carb clearer down the air intake infront of the MAF whilst on idle. This will clean or go some way to cleaning the MAF and might just sort you out before you spend £50 on a new unit.

£50? More like £130! That's a great price. Where can I get one?

Could be a lead. for peace of mind get magnacore leads. The set costs £90 from rpi but the car will feel like new. Dont get cheap leads. Done that got the t shirt and £350 worth of new gas injectors froma robbing barstool when the wife took it in.
The maf would play up all the time when mine went (thor engine like yours) . Plugs, leads then go down other routes. A plug lead may have come loose so check all those first

Hi Guys,

Thanks for the advice. Leads n plugs changed 3 days ago but just put a trolley jack on my acc pedal and removed MAF sensor - car ran perfect! Just popping out to buy a nice replacement.