Lexus LS400 (1990 - 2000) - 94 4.0 petrol, bad misfire - front 4 cylinders

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Mon 26 May 2008 23:49
94 4.0 petrol, bad misfire - front 4 cylinders - dubz
hi my bosses lexus has done about 149,000 miles, and its now misfiring extremely badly on the front 4 cylinders, after driving it in and out of the workshop every day for 6 months, we've put new plugs and leads on it had the inlet manifold of and nothing seems like nothing was blocked, but very coked, we thought it may be something to do with the E.G.R. valve (exhaust gas recycling), please can some one help?

Edited by Pugugly on 27/05/2008 at 00:11

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Tue 27 May 2008 16:20
94 4.0 petrol, bad misfire - front 4 cylinders - drivewell
Hi Dubz

I guess the lack of response is not down to dis-interest, but simply a reflection of the rarity of the vehicle, and therefore lack of technical experience on here.

Did find this thread over on the Lexus forum which may be a starting point?

www.lexusownersclub.co.uk/forum/index.php?showtopi...9
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Wed 28 May 2008 23:52
94 4.0 petrol, bad misfire - front 4 cylinders - Screwloose
dubz

Does this misfire happen at idle or driving? Have you had it checked for fault-codes? [Probably only the dealers have the kit.]

What about the compressions - have they been checked for stuck valves? Could this be stuck injectors - are the plugs wet? What else has been checked or tested? Was it only the front of the inlet manifold that is coked?
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