Grid Heater Light

If your grid heater light comes on while driving is a sign of a high return rate to the fuel tank or the fuel pressure in the rail is dropping. In my case, I was traveling towards McCall ID and climbing a grade with my utility trailer. All of a sudden the grid heater light comes on and chimes multiple times. Which I thought was weird. I had to complete my climb up the grade for a safe spot to pull over. Once I did get pulled over I shut down and looked there was fuel everywhere. I the grid heater light comes on while driving I highly suggest you get to a safe spot and shut down as quickly as possible.

Checking The Injector Lines

Now that I've got the truck home in the yard. I took some time to re-prime the rail and get it started. Even with as big of a leak, it was very possible to prime the rail fairly quickly and start the engine. 

WARNING: Being fuel is present and fire danger is always a risk make sure to have a fire extinguisher handy that is rated for fuels and oil fires.  

WARNING: Do not put your hands near the injection lines while running. High-pressure fuel injection injuries are very painful and can cause serious infections. Please keep your hands away from the lines. Use cardboard chunks if you want to see where the fuel is sprayed from. 

Once the engine is running look closely and you can see which line is spraying fuel. Again do not put your hands or body near any spraying fuel. 

If it's not possible to start because of too big of a leak you can order a rail plug that you can remove one line at a time then cap the rail and see which line is leaking this way so if the line you remove is plugged and now it starts it could be the line or a bleeding injector. I know this is kind of tough being every time you open the rail to change the plug you have to reprime the rail. Just as you'll see in my video first turn of the key the ECM will do a prime cycle, after the lift pump stops, just bump the starter again it will re-run for the next prime cycle of time. Make sure you give time to let the pump prime the system and allow for cool-down time on the starter. 

Installing Number 4 Injector Line

It is pretty straightforward for installing the number 4 injector line. Count back to the number 4 injector line from the front. Now you'll need a 3/4 inch wrench and a 10mm socket and ratchet with extension. First, remove the two 10mm bolts one in the manifold just under the injector line nut at the head for the intake manifold cover and the other 10mm bolt holding the number 4 injector line. Now Using the 3/4 inch wrench loosen the two injector line nuts and remove the injector line. Install in reverse order.

• Sockets - 8mm, 10mm, 11mm (or 7/16"), 13mm, 15mm, 24mm

• Torque Wrenches (1/4" and 3/8" inch)

• Wrenches - 10mm, 24mm, 3/4"

• Torx bit driver - T10

Removal of all 6 common rail injectors

1. Disconnect both negative battery cables from both batteries. Cover and isolate the ends of the negative cables. This is just done for pure safety for you and the electrical system.
2. Remove the decorative cover (10 mm) breather tubes hooked to the valve cover.
3. Remove the valve cover. There are six 10mm bolts holding the valve cover in place. 

4. Remove all the 8mm nutted electrical connections on top of all injectors and unplug the 3 electrical connectors on the driver side of the lower valve cover.

5. Remove the lower half of the valve cover, which has seven 10mm bolts. Be aware that there is one at the very front edge and the very rear edge.

6. Remove all 6 exhaust rockers. Make sure to lay them out in the exact order you removed them from the engine. Have a small table covered with rags and set the table beside the truck, and from front to rear, lay the rockers out in that order.

7. Remove the intake horn. There is one 10mm bolt holding the dipstick tube, then 11m (7/16) socket loosen the intake boot clamp. Then there are four 10mm bolts holding the intake tube to the intake manifold and grid heater. Lay them over to the driver's side out of the way.

8. Remove all 6 injector lines from the rail to the head. There are 10mm bolts holding some of the lines that are bolted to the intake cover plate. Using a 3/4 inch wrench, you'll loosen both ends and remove each line. Again, lay them out in the exact order next to each cylinder rocker arm in order. 

9. You'll need a 24mm open-end wrench or a box-end that is thin. Remove each connector tube nut. Using a flat-blade screwdriver and carefully pry each tube from the cylinder head. Suggested to lay each connecting tube next to each cylinder rocker arm for inspection.
10. Remove all twelve 8mm bolts holding the injectors in place. 

11. Using a flat-blade screwdriver and place the tip under the hold-down collar of each injector and either twist the screwdriver to lift the injector out or lever off a head bolt and lift each injector out. Suggested to lay out each injector next to its cylinder's rocker arm for inspection. 

WARNING: Do not attempt to replace just one injector that is damaged. Injectors should be replaced in complete sets.

NOTE: I also highly suggest that you do not replace with Bosch stock injectors; Bosch stock injectors are not flow-matched or pop tested before sale. This means you do not have a matching set for your truck, and the injector failure rate is much higher on unmatched injectors. You should buy a set of injectors that have been pop-tested and flow-matched for your application. 

NOTE: Bosch injectors typically come with an 8-digit hexadecimal code on the injector, which is supposed to be programmed into the ECM to set the offset of each injector, hence why Bosch injectors are not tested as a set. I highly suggest you DO NOT buy Bosch injectors!, but an aftermarket set that can be tested as a set of 6 injectors.

WARNING: Always replace common rail injectors as a complete set of 6 injectors. Not doing so results in poor engine performance, and economy being older injectors will most likely be out of spec (Advanced timing, poor spray pattern, etc)

WARNING: There are differences in injectors between early and late 3rd Generation trucks. Do not exchange early and late injectors; engine damage will occur. 

NOTE: If your truck happens to be an automatic transmission, be aware that the added power of injectors might make the transmission slip. This depends on the final ratio of the truck to the ground, and oversize tires will impact this issue.

Inspection of the injectors

To inspect the common rail injectors, you will need to clean off all the fuel and oil from the injectors. Brake clean and rag should suffice.
1. Look for burrs or wear on the injector inlet.
2. Check nozzle holes for hole erosion or plugging. You will need a magnifying glass to really see the nozzle.
3. Inspect the end of the injector nozzle for mechanical damage. Strike damage etc.
4. Look for cracks at the injector nozzle end. 
5. If any of these conditions occur, have the entire set of injectors rebuilt.

Installing common rail injectors

Most injectors are rebuilt these days. There are a few companies that do sell new flow match injectors like Big Bang Injectors (BBI), even Diesel Auto Power (DAP) 

1. Unpack all 6 common rail injectors and verify that the copper shims are included on the nozzle. If not, you will need to install the copper shims. If the shim slides on easily, you will need a small dab of axle-bearing grease to hold the shim in place during installation. A new copper shim with the correct thickness must always be reinstalled after removing the injector. Measure the thickness of the injector shim. Shim Thickness: 1.5 mm (.060”)

2. Thoroughly clean the fuel injector cylinder head bore, making sure there is no debris or old copper shims in the bottom of the bores. You can use a shot of brake cleaner and a rag to wipe out the holes. 

3. Most injector suppliers typically already have the O-rings on the body of the injector. If not, make sure to install that o-ring at this time and lightly lube the o-ring with clean engine oil.

4. Install the new injector. Pay attention to the location of the inlet port on the side of the injector, and it should face the intake manifold in line with where the crossover tube goes. Push down the injector hold-down collar and seat the injector completely into the bore. 

5. On each injector, you want to tighten the two 8mm bolts alternately till 44 inch/pounds. This just ensures the injector is fully seated in the bore. I typically back off this torque to allow the injector to find the center of the cross-over tube in the next step.

6. Install all 6 crossover tubes. Torque the crossover tube nut to 11 foot/pounds. This will now seat the crossover tubes into the port of the injectors. 

7. Now torque all the injector hold-down bolts to 89 inch/pounds. Make sure to alternate back and forth and not get one side buried into the bottom. Should be even and level. 

8. Torque the crossover tube nuts to 37 foot/pounds. You will need a 24mm socket and then torque the crossover tube nuts.

NOTE: You need a T10 Torx driver to remove the MAP/IAT sensor to gain room for torquing crossover tube #4.

9. Inspect the o-ring gasket before installing and replace it if any damage is seen. Reinstall the lower half of the valve cover. There are seven 10mm bolts. Remember, the front and rear have a bolt near the sealing lip.

10. Hook up all the injector wiring back to each injector. There is no polarity to the injector, so it doesn't matter which wire goes on which post. Do not over-torque the wire nuts; they only need 11 inch/pounds of torque. Plug in the 3 engine harness plugs to the lower half. 

11. Install the exhaust rocker in the order you had laid out. Make sure the push rods are down in each tappet. The torque on the hold-down bolt is 35 foot/pounds. Be aware that maybe a few cylinders where the tappet is up on the cam lobe, but also even a pushrod that isn't seated will look similar. Make sure the pushrods are in the tappets. If you kept the rockers in order, then you would not need to do a valve lash.

12. Install all six high-pressure rails between the rail and the crossover tubes. If you kept them in the order, it shouldn't be too hard. Torque the line nuts to 22 foot/pounds.

13. Reinstall the upper valve cover and crankcase vent tubes. The six valve cover bolts are torqued to 18 foot/pounds.

14. Check the condition of the grid heater gaskets. Replace if needed. Reinstall the air horn and grid heater. Torque the four 10mm bolts to 120 inch/pounds. 

15. Attach the dipstick tube with the one 10mm bolt. Tighten snug.

16. Tighten the intake boot clamp.