Slow starting i have a 2000 3ltr. bighorn which requires a lot of cranking befor it fires, no problem once it is running, I have changed the glow plugs but this did not cure the problem. any ideas would be great, cheers Allan.

Faulty glow plugs or air in fuel system

I think 1st off the battery should be checked for load test. If the battery is not good everything will struggle.

problems include
slow cranking speed
faulty injectors
no fuel to the injectors -- check stop solenoid , air in the fuel system, fuel control module (if common rail diesel and high pressure pump not delivering the required extreme high pressure for the injectors)

Do you mean it cranks a lot before it fires up or starts?

Not sure what baffles and what are slip ons (thought they were(are) a type of smart casual shoes).

An engine needs compression, fuel, spark and timing in order to run. Although some engines need cranking more than others before the fuel is present in the cylinders in the right quantity for combustion, it is never more than a few seconds for an engine in good order, though some older engines seem to need a moderate amount of throttle opening in order to start successfully and fairly quickly.

If the engine doesn't start at least one of those essentials is absent, sometimes due to an immobiliser not disarming. I suggest you physically check the presence of a quality spark. If it is there as soon as the key is turned the problem is likely to be related to the slow build-up of fuel pressure for a number of possible reasons.

If your truck is a diesel, it is probably a glow plug problem, check the glow plug fuse, if not blown, check the glow plugs

First it's "diesel" , your not giving a lot of information here but for a diesel to fire it will require 350 psi of compression. It sounds like it will run if you pull it, that indicates you may be spinning it faster to get higher pressuer or heat build up in the cylinders to actually fire the fuel. I take it the glow plugs or working? If not get them working first before you go on. I assume it may be a high mileage diesel it could have been dusted and have low compression.

First, lets be clear with terms. To crank is to turn the engine over, you can do this manually with a wrench on many vehicles. It requires no spark or air. To turn over or to fire is when you achieve combustion. Example: You could pull the spark plugs on a vehicle and turn the key and it would crank, but it wouldn't fire or turn over.

Now it sounds to me like your vehicle is cranking but not firing unless you pour gas in it. My first thoughts are fuel system. I'm assuming it can't be fuel pump because it runs once it fires. Perhaps the fuel pump isn't priming itself, or perhaps somehow air is getting in the line between the injector and fuel pump? Test the fuel pump first by turning the car from off to on (not starting, just on). You will usually hear a short buzzing noise coming from the engine bay that stops shortly afterwards, that's your fuel pump pressurizing the line. (Pro Tip: If you ever try to take your key from off to straight to start and the vehicle doesn't start on the first try, but does the second time no problem, try delaying at on for a moment before trying to start. This gives your fuel pump time to pressurize the line.) Assuming your fuel pump is charging the line, the next place to look would be at the path the fuel takes to the throttle body. When you crank it over and it doesn't start, are you getting any fuel? If you can't see where the fuel enters the system try smelling the exhaust while cranking without it firing, if it smells of fuel you're good and need to look at air flow and spark, if not it's a fuel issue.

Past that, I'll leave it to someone more experienced than myself, but that would be how I troubleshot my own vehicle.

Did you pull a spark plug placing it against the block while cranking the engine over and see the spark ? or "fire" as you call it. Theres a number of things that could be wrong, first is the engine cranking over fast enough ? you say you had too boost it if the engine cranks too slow it won't start. Another thing you can check is if you have the digi 2 fuel intake (I've had this problem before) they were know to flood themself if you held the key to start too short, if this is the case simply unplug the fuel rail connector on the far end of the transmission side of the engine keep cranking the engine if its flooded it will start (hood the gas pedal too the floor while cranking and fuel rail unplugged) once it fires let off pedal and its always easier to have some one ready to plug that connector back on as soon as the engine fires before it runs out of fuel then your back to square one. The only other thing (worse case) is when the person crossed the battery while boosting it you may have fried your ECM, its located on the left side of the car under the windshield you have to get at it from the outside by removing the black trim peace that is under the hood where your wiper arm linkage is, a small box with about 2 to 4 main wire harness connectors its held in place by four 10mm bolts. Well thats a few things you can check out hope it helps and good luck.

vdubs 4-ever

I have a 1998 Bighorn 3.0L if the wrong grade of oil is used in the motor it miss fires and runs rough, due to the injectors being oil pressure controlled, I have heard of extreme cases causing a failure to start when cold. good luck

Sounds like your glow plugs are bad. Have them checked.