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Matt, Engineer
Category: Car
Satisfied Customers: 21871
Experience:  Honors degree in Mechanical Engineering, worked 8 years as a Formula 1 engine engineer.
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land rover discovery: 2000 land rover discovery 2...rough almost

Customer Question

2000 land rover discovery 2...rough almost impossible start...diagnostic said to replace camshaft sensor...did, ran 1 day , now same issue, but no diagnostics??
Submitted: 3 years ago.
Category: Car
Expert:  Matt replied 3 years ago.

can you tell me what engine this is please?

the 3.9 V8 petrol?

how many miles are on it and when was it last serviced?
Customer: replied 3 years ago.

Yes, & was serviced less than 5k ago...motor was rebuilt approx. 20k ago...vehicle has 96k on it thx, Hayden

Expert:  Matt replied 3 years ago.
Hello Hayden

Ok if this is the V8 then I'd suggest the next thing to replace is the crank position sensor at the back of the engine

sometimes the diagnostic will confuse the cam and crank sensor and throw up the wrong code
Customer: replied 3 years ago.

ok, It started & ran well for 1 day. OK but doesn't look easy to get to...any tips?

Expert:  Matt replied 3 years ago.

The crank sensor is best accessed from underneath, once you've got the car up in the air its relatively easy to get to
Customer: replied 3 years ago.

I haven't installed it yet...I will answer when I do..thx, Hayden

Expert:  Matt replied 3 years ago.
no problem
Customer: replied 3 years ago.

wasn't the problem, still wont run? h


Expert:  Matt replied 3 years ago.

next step is to go back to basics a little

1st check for spark by removing one of the spark plugs and plug it back into its lead and rest it on the metal of the engine ( DO NOT hold it on place by hand) then have your assistant turn the engine over whilst you watch the plug. It should give a fat blue spark at regular intervals.

If not then check that there's power to the coil pack (at the other end of the plug lead) using a meter. If there’s 12V at the pack but no spark then check the ECU power supply (fuse and relay) and also the connections to the crankshaft speed sensor.

If there is a spark and its still not starting then its likely that the ECU isn't opening the fuel injectors, if the injectors are working you can hear them click - its difficult to hear them with background noise so use a long screwdriver like a stethoscope, placing the handle end in your ear and the metal tip against the body of the injector whilst your assistant turns the engine over.

If you can't hear anything check the ECU power is present by measuring voltage at the fusebox and on its relay socket if OK then check the connections to the crank speed sensor and consider replacing this sensor if the wiring / connections look OK

If the car will start using a squirt of quick/ easi start into the intake then this confirms the problem is lack of fuel

Also its worth checking that the electric pump that feeds the injectors is working correctly, it should run for a few seconds then switch off when you first turn the ignition on. If you remove the filler cap to the fuel tank and listen inside while your assistant flicks the ignition you should hear it clearly

Customer: replied 3 years ago.

OK, it has spark & is getting fuel, a local mechanic has checked it out & is thinking a timing chain/belt...what do u think, he cannot do this kind of work as u recommend anyone in this area...Rehoboth beach, De.

Expert:  Matt replied 3 years ago.

if its the 3.9 V8 then its very unlikely to be the timing chain as its a very short and almost never gives issues as this is an OHV / cam in block / pushrod engine like a chevy small block

what can happen with these engines is the cam wears badly so valves no longer lift fully

this can be checked by popping off the rocker covers and turning the engine by hand to check the amount of valve lift on each position

as for a Landrover mechanic


CJ's Beach Bays Inc XXXXXbr/> Lewes, DE 19958
Customer: replied 3 years ago.

So I would need new camshaft? or complete rebuild?

Expert:  Matt replied 3 years ago.

usually you can get away with a set of new followers and a new cam - you usually replace the cam chain at this point as well

also fit a new oil filter and fresh oil at the same time typically

this is about $400 of parts and a days labour
Customer: replied 3 years ago.

CJs now says its the flywheel :( what do u think ? $3000. repair

Expert:  Matt replied 3 years ago.


that sounds pretty unlikely to me as the trigger wheel is a series of holes drilled into the flywheel


unless something has gotten into the bellhousing and damaged the edges of the holes then there should be no need to replace the flywheel

this can checked out by removing the crank sensor and looking into the hole whilst turning the engine by hand