sidepod
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Chaps,
Following a recent minor (escalating quickly into a major) incident, here’s my get you home guide to the Westy fuel injection. (2.4D, NA).
Engine cranks but won’t fire.
The engine is cranking so we’re happy it’s not starter motor related. For the purposes of this let’s assume we have compression.
The fuel injection system has two basic elements. Mechanical/fuel and electrical.
If the engine is cranking with no spluttering or attempt to fire then it’s a reasonable bet the fault is electrical. If it’s spluttering and low on power then it’s probably a fuel fault.
There are essentially three electrical components involved.
First thing to check is the glow plug fuse link. Under the bonnet, on the bulkhead by the battery is a small black box with two thick red/white wires going in.
Flip open the lid and examine the metal strip fuse. They have a bad habit of cracking. If it’s cracked, replace it. 75p from G&S or the main VW dealer. Good to carry a spare in the van.
Now check the supply to/from this fuse box. The input comes via the glow plug relay (102) in the main fuse box in the cab. Connect the voltmeter to the battery neg and the any of the terminals in the glow plug fuse box. Switch on the ignition so the orange glow plug light shows on the dash.
You should hear the relay (102) pull in and you should see 12v on the meter. Do this quickly as the relay will time out. If there is no 12v at the meter then it’s likely your relay is duff or (in my case) the connection inside the fuse box has failed. It’s a relatively simple task to test the relay on the bench with a 12v supply/continuity check.
Assuming there is a healthy supply at the glow plug fuse then you can confirm the link to the glow plugs. Simply locate the glow plug (choose the one nearest the battery as they’re linked in series. If this one has a supply then it’s likely all the others do.) Test for voltage between here and the battery earth.
Worth noting, the glow plug relay times out after a short time (approx. 10 seconds) but it does re-energise during cranking.
Next thing to check is the fuel cut off/solenoid. This is a simple electrical valve that flips open when you turn on the ignition and off when you stop the engine. It simply cuts the fuel supply to the engine (without it, you’d need to stall the engine). It’s designed to fail closed so if you have no 12v supply or its failed then you have no fuel.
With the radiator in service position (bonnet up/cross member unbolted), locate the fuel pump and you’ll see the solenoid with a single wire connected to it. Later vehicle will have a plastic anti-theft cover which is part of the immobiliser.
To confirm its operation get somebody to switch on the ignition to the glow plug light (orange) position. You should hear/feel the solenoid pull in. This can also be done with a test lead/crock clips linked directly from the battery. Take a long screwdriver and touch the tip on the spade terminal of the solenoid. Clip the test lead to the top of the screwdriver blade, the other end to the positive of the battery. (make sure the blade of the screwdriver isn’t touching any earthed metal!)
Next check is that you still have a supply to the solenoid whilst cranking the engine. The ignition switch can be problematic causing loss of supply.
Take your voltmeter. Clip the positive lead on to the solenoid terminal, the neg on any convenient metal work or battery terminal. Crank the engine and make sure you have a consistent 12v.
If all of the above prove ok then it’s a fuel supply issue.
Start by removing the two fuel lines to the filter (one blue, one black). These are flow and return from the tank. The blue is the return (I think), the black is the supply. Blow down the black one.
You should hear bubbles in the main tank. Debris in the tank can block the take off.
Next take a 17mm spanner and trace the supply line from the filter to the injection pump.
Crack open the union and crank the engine. (Note – If you’re doing this on your own you can easily crank the engine from under the bonnet. Starter motor. Large red cable is the battery supply. Next to this is a spade terminal with the link from the ignition switch. With a short test lead link the large cable to the spade terminal and the motor will crank the engine. Again, take care not to short this out). You should see fuel dribble out. Nip up the union.
Check the fuel supply to all of the injectors. Crack each union in turn and crank the engine. Fuel should be visible at reasonable pressure. Nip up the unions again.
If all else fails then try Easy start in the air intake. Remove the large hose connecting the inlet manifold to the air filter. Spray Easy start in the manifold and crank the engine. It should start.!
So, if it turns out to be an electrical fault it should be a relatively easy get around to by pass whatever has failed. If the glow plug relay proves to be problematic then disconnect the input cable from the glow plug fuse box and simply touch it to the positive battery terminal. Hold it the there for a count of 7-8 seconds to heat the glow plugs then turn the ignition key.
If the stop solenoid has failed or it turns out the ignition switch isn’t allowing a supply then simply hard wire the solenoid to the battery to hold it open. You could even unscrew the valve (24mm spanner – very fiddly) and remove the plunger from the pump thus allowing fuel to flow. (Note a new valve costs about £65).
Good luck.
Pod.
Following a recent minor (escalating quickly into a major) incident, here’s my get you home guide to the Westy fuel injection. (2.4D, NA).
Engine cranks but won’t fire.
The engine is cranking so we’re happy it’s not starter motor related. For the purposes of this let’s assume we have compression.
The fuel injection system has two basic elements. Mechanical/fuel and electrical.
If the engine is cranking with no spluttering or attempt to fire then it’s a reasonable bet the fault is electrical. If it’s spluttering and low on power then it’s probably a fuel fault.
There are essentially three electrical components involved.
- The glow plug circuit consisting of a relay in the fuse box (102), a fuse link located under the bonnet next to the battery and the glow plugs themselves.
- The fuel cutoff/stop solenoid located on the injection pump.
- The ignition switch.
First thing to check is the glow plug fuse link. Under the bonnet, on the bulkhead by the battery is a small black box with two thick red/white wires going in.
Flip open the lid and examine the metal strip fuse. They have a bad habit of cracking. If it’s cracked, replace it. 75p from G&S or the main VW dealer. Good to carry a spare in the van.
Now check the supply to/from this fuse box. The input comes via the glow plug relay (102) in the main fuse box in the cab. Connect the voltmeter to the battery neg and the any of the terminals in the glow plug fuse box. Switch on the ignition so the orange glow plug light shows on the dash.
You should hear the relay (102) pull in and you should see 12v on the meter. Do this quickly as the relay will time out. If there is no 12v at the meter then it’s likely your relay is duff or (in my case) the connection inside the fuse box has failed. It’s a relatively simple task to test the relay on the bench with a 12v supply/continuity check.
Assuming there is a healthy supply at the glow plug fuse then you can confirm the link to the glow plugs. Simply locate the glow plug (choose the one nearest the battery as they’re linked in series. If this one has a supply then it’s likely all the others do.) Test for voltage between here and the battery earth.
Worth noting, the glow plug relay times out after a short time (approx. 10 seconds) but it does re-energise during cranking.
Next thing to check is the fuel cut off/solenoid. This is a simple electrical valve that flips open when you turn on the ignition and off when you stop the engine. It simply cuts the fuel supply to the engine (without it, you’d need to stall the engine). It’s designed to fail closed so if you have no 12v supply or its failed then you have no fuel.
With the radiator in service position (bonnet up/cross member unbolted), locate the fuel pump and you’ll see the solenoid with a single wire connected to it. Later vehicle will have a plastic anti-theft cover which is part of the immobiliser.
To confirm its operation get somebody to switch on the ignition to the glow plug light (orange) position. You should hear/feel the solenoid pull in. This can also be done with a test lead/crock clips linked directly from the battery. Take a long screwdriver and touch the tip on the spade terminal of the solenoid. Clip the test lead to the top of the screwdriver blade, the other end to the positive of the battery. (make sure the blade of the screwdriver isn’t touching any earthed metal!)
Next check is that you still have a supply to the solenoid whilst cranking the engine. The ignition switch can be problematic causing loss of supply.
Take your voltmeter. Clip the positive lead on to the solenoid terminal, the neg on any convenient metal work or battery terminal. Crank the engine and make sure you have a consistent 12v.
If all of the above prove ok then it’s a fuel supply issue.
Start by removing the two fuel lines to the filter (one blue, one black). These are flow and return from the tank. The blue is the return (I think), the black is the supply. Blow down the black one.
You should hear bubbles in the main tank. Debris in the tank can block the take off.
Next take a 17mm spanner and trace the supply line from the filter to the injection pump.
Crack open the union and crank the engine. (Note – If you’re doing this on your own you can easily crank the engine from under the bonnet. Starter motor. Large red cable is the battery supply. Next to this is a spade terminal with the link from the ignition switch. With a short test lead link the large cable to the spade terminal and the motor will crank the engine. Again, take care not to short this out). You should see fuel dribble out. Nip up the union.
Check the fuel supply to all of the injectors. Crack each union in turn and crank the engine. Fuel should be visible at reasonable pressure. Nip up the unions again.
If all else fails then try Easy start in the air intake. Remove the large hose connecting the inlet manifold to the air filter. Spray Easy start in the manifold and crank the engine. It should start.!
So, if it turns out to be an electrical fault it should be a relatively easy get around to by pass whatever has failed. If the glow plug relay proves to be problematic then disconnect the input cable from the glow plug fuse box and simply touch it to the positive battery terminal. Hold it the there for a count of 7-8 seconds to heat the glow plugs then turn the ignition key.
If the stop solenoid has failed or it turns out the ignition switch isn’t allowing a supply then simply hard wire the solenoid to the battery to hold it open. You could even unscrew the valve (24mm spanner – very fiddly) and remove the plunger from the pump thus allowing fuel to flow. (Note a new valve costs about £65).
Good luck.
Pod.
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