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Greg, Technician
Category: Car
Satisfied Customers: 1130
Experience:  Automotive diagnostic tech
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We have a ex military L/R 110 with 3.5 V8, problem has occured

Customer Question

we have a ex military L/R 110 with 3.5 V8, problem has occured over the last 150 miles
bad back fire thro exhaust over 1000rpm and no power over that, not overheating good sparks, changed fuel filters, has electronic ign fitted over the last few years, new plugs 1500 miles ago, starts first turn hot or cold so have ruled out compression but not checked them checked vac adv pipe OK, not checked ign timeing yet, problem came on gradually over a 150mile journey, does not use oil or lose water
Getting a bit frustrated
Submitted: 2 years ago.
Category: Car
Expert:  Greg replied 2 years ago.
Name is***** goal is to provide you with excellent service – if you feel you have gotten anything less, please reply back,
First do a compression test , if shows all the same compression
then do a intake manifold gasket vacuum leak test .
Typical on this engine is the manifold leaking ,
If you see on the compression test a few cylinders down then do a leakdown test on these cylinders , also known to burn valves
Then the ignition timing would be a good check maybe a tod lose and moved get the timing light on it .
Sometimes best to forget the book timing set up and adjust the ignition by retarding or advancing to the point the engine runs smooth
and takes on accelaration with out a hick .
Do this first then get back to me ,