Frequently Asked Questions (updated 8/22/2012)


1)  Do you remanufacture injectors?
2)  Can you just do my nozzles and send them to me, my truck is a daily driver and I can't pull it out of service to send you the injectors?
3)  Is testing and balancing really necessary?
4)  How do you test and what does it mean to me?
5)  Do you sell injectors?
6)  Are reman injectors any good?
7)  If a body is cracked the injector is bad, are there other reasons for having to replace an injector?
8)  Are stainless steel 5.9 injectors better than standard 5.9 injectors?
9)  Do you do 12 and 24 Valve mechanical Injectors?
10) Do you repair CP3 pumps or have high output pumps available?
11) How big of an injector (or flow of nozzle) do I need?
12) Do you make larger bore custom High pressure lines?
13) Do you service Ford 6.4 injectors?
14) Do I need to replace my High Pressure cross feed tubes when I replace my Cummins injectors?
15) Can I remove the injector edge filter for better flow?
16) What about extra filtration?
17) I have nozzles from someone else and want to find out what they flow. Can you do that and what is the cost?
18) My balance rates are off, what can I do?
19) Do you modify the latest Piezo injectors for the 6.7 Ford and the LML Duramax?


1) Do you remanufacture injectors?

At this time we do not remanufacture injectors. The time and component costs of doing the job correctly are equivalent to purchasing a new Bosch remanufactured unit. From what we have seen to date they are the only ones remanufacturing them correctly.

We can however repair injectors for items such as broken stators, damaged high pressure fittings, blown internal high pressure seals, or a no fire condition caused by gummed up fuel or extended downtime. We do not “remanufacture” your injectors which by definition means the injectors are made “as good or better, than new.”

2) Can you just do my nozzles and send them to me, my truck is a daily driver and I can't pull it out of service to send you the injectors?

As much as we would like to help out we really would't feel comfortable with sending nozzles out without final assembly and testing on our side. We have done hundreds of engine sets now and can say that most of the time we find an issue with a used set of injectors that requires attention. Sometimes major, sometimes minor, but we correct them if possible at final test. We have done a few (a very few) nozzle only sets but based on our experience, when we do, we are playing with fire.

Our suggestion is to keep running until your injector set needs attention. We could then work up a set of new/reman oversized injectors and send them to you, at which point you install and send your old injectors back as cores. We allow a 30 day window for core return so this works out well for most in your situation.

This brings up another issue regarding modification of a daily driver. If the vehicle is your only source of transportation, be careful with any modifications. Keep in mind, in general, the greater the modification, the lower the reliability. Even mods disguised as "reliability improvements" such as filters, fuel pumps, and dual HP pumps can compromise reliability if done carelessly. Breaking into the fuel system whether on the low or high pressure side must be done with extreme care, for example, lint from a shop towel in the wrong place can keep an injector from firing or worse, hang it open and burn down a cylinder. Have fun but be careful. Having a spare vehicle down for a few days is usually not a big problem, losing your primary mode of transportation can be.

3) Is testing and balancing really necessary?

Take a look at the comments from some of the most prominent tuners and builders in the country shown on our "Why Exergy" page. The real question is can you really expect top performance without it? Do you want to take the chance that all is well on an install only to find later you have a bad injector and have to do it all over again? Take a look at the top mechanical fuel system users in the country (P-Pump 12 and 24V) they balance the pump and injectors as a set. Bottom line - equal fuel and equal timing for all cylinders converts into wins.

The mechanical guys can change injectors in a flash compared to common rail systems so there are many that do no testing whatsoever. However, the design of mechanical systems yields a much "softer" failure mode. If a mechanical injector or nozzle fails, smoke is the result. Failure of a common rail injector can lead to engine destruction.

When we test and balance we adjust internal assembly dimensions that may have drifted over time from their proper specifications. We measure and correct for proper operations across the operating range from idle to full power. This becomes increasingly important with higher nozzle flows.

4) How do you test and what does it mean to me?

We fully test from idle to full power using factory calibration points and a few of our own added for the high performance market (see sample datasheet). We can fully map injector sets and have done so for a number of customers who want to best utilize their stand alone ECU or EFI Live capabilities.

We use equipment developed and used by Bosch for the design and development of diesel fuel systems (specifically Common Rail) and have the expertise on staff to properly operate and maintain this very sophisticated equipment. Some on our staff were involved in the development of this equipment and Common Rail Injectors when we were at Bosch. Our "toolbox" is very extensive along with our knowledge base. Most of us have been in the diesel business in excess of 20 years and have worked on the design and development of mechanically and electronically controlled diesel fuel systems for everything from ships to single cylinder utility engines.

With our equipment we are able to measure not only injection quantity and timing, but shot-to-shot consistency. Based on the results of the injector sets we have analyzed from others neither is being controlled let alone measured. Changes are made that bring the injectors into calibration at a few low pressure test points, but in doing so the hydraulic response of the injector to the electrical drive signal is affected. We have seen the beginning and end of the injection event vary in excess of 3 degrees crank on a freshly "rebuilt and blueprinted" injector set. Our testing capability is far beyond normal service center capabilities.

If you choose to work with another performance supplier, ask first for a copy of a typical test summary sheet. Do they provide injector output at multiple test points? Do they test at full rated pressure and output (24,000 psi for 5.9, LB7/LLY... 27,000 psi for 6.7/LBZ/LMM)? Do they measure injector stability? Can they provide an output vs pulse width map at various rail pressures? Can they measure injector response time to drive signal?

If we test your injectors and find them to be within factory specifications for output timing and consistency it does not however, mean they are as good as new. The wear they had when they arrived is the same as when we are done testing. We do not magically make them better. In general 5.9 and LB7 injectors are worn out at 140,000 miles. LLY/LBZ/LMM and 6.7 injectors last longer. We have tested many sets that meet specifications with over 200k miles on them. This is a VERY general number and depends on many factors including fuel, duty cycle and modifications. Keep this in mind for your end use. If you are building your dream vehicle with top of the line components, using old, worn injectors may not be the best way to go. If you are on a tight budget, and the injectors test fine, then that may be the best way to go. Something in-between is a more difficult decision. It is easy to put 1/2 to 2/3 the cost of a set of reman injectors into baseline testing and repair of a worn set. When we are done, the injectors function as they should, but the time to "wear-out failure" is the same as when we started.

5) Do you sell injectors?

Yes, see our website or check with our dealers for pricing and availability of Genuine Bosch remanufactured or new injectors for Duramax and Cummins. We also have injectors available for the 7.3 and 6.0/6.4/ 6.7 Powerstroke. Our prices are seldom the lowest but we only sell injectors and components that are the best available. Standard core return requirements apply.

6) Are reman injectors any good?

When done properly (and at this time in our opinion, the only proper remanufacturing is done by Bosch) the injectors are as good as new and better than the original injector design. All wear components have been replaced with new, and in most cases improved parts, making remans an excellent value.

7) If a body is cracked the injector is bad, are there other reasons for having to replace an injector?

There are components in the injectors that wear over time with the LB7 Duramax and 5.9 Cummins having the shortest life of all Bosch Common Rail injectors. After introduction of these groundbreaking products Bosch continued to tweak the design in effort to improve fuel control and durability. The LLY/LBZ/LMM and 6.7 injectors are the fruits of this labor and hold up much better than the first generation series. In talking with service shops, customers and others across the country the general consensus is under normal conditions you can expect to need injector replacement at 140k miles with the 5.9 or LB7 series (give or take, there are exceptions to everything). The replacement injectors (Genuine Bosch remans or new) are more durable than the OEM versions but are still not as good as later model (LBZ/LMM 6.7) design iterations.

8) Are stainless steel 5.9 injectors better than standard 5.9 injectors?

Stainless steel bodies do not exist, the 5.9 series injectors have been changed over to the same material used for the higher pressure rated 6.7 series injectors. With the new body material the new 5.9s are stronger but still not as good as the 6.7 injector which has been designed from the ground up to handle higher injection pressures. In terms of reliability and strength the new body material is an improvement over the original. But is not, repeat, is not stainless steel.

9) Do you do 12 and 24 Valve mechanical Injectors?

Yes, we can EDM and hone to your to your specification. Spray angle changes are possible within limits. You must know exactly what you want in terms of nozzle, flow target, and NOP for us to do the work. If you need help several of our dealers have extensive application knowledge for 12 and 24V engines that you can access to meet your goals.

10) Do you repair CP3 pumps or have high output pumps available?

No, we do not repair CP3s. We do have a line of high output CP3s, the first design with 30% greater displacement known as the 10mm Stroker pump. A larger pump is in development with 50% greater displacement known as the 12mm Stroker pump. We are basing these pumps on either a LBZ/LMM or 6.7 pump. We do not offer stroker LB7/LLY or 5.9 pumps at this time. We can fit a "straight" FCA connector on the LBZ pump for easier mounting in the LB7 application. We can also equip the LBZ/LMM pump with a rear output HP fitting for additional mounting options.

11) How big of an injector (or flow of nozzle) do I need?

Making a set of injectors to achieve your power target as smoke-free as possible is no problem. However, specifying a set that best meets the targets for your application is best done by a dealer, especially at high power levels. There are a number of variables to consider, and our specialty is more in building the injectors than specifying them. The price from a dealer, or direct from us is the same, so it is best to get as much dealer application experience involved as possible. Please visit our website for a list of our dealers. We believe the experienced dealer approach to any project is the best way to maximize your performance investment dollar.

12) Do you make larger bore custom High pressure lines?

Yes, see our website or call for specific information regarding fabrication. Typical line size is 8mm OD with a 3.5mm bore. 12 x 1.5, 14 x 1.5 and 18 x 1.5 fittings are available.

13) Do you service Ford 6.4 injectors?

In 2008 - 2009 we spent several months developing test equipment and a test procedure for this injector. Throughout this time we were unable to match the results on our test bench with those in the vehicle. In other words, the outputs/performance on bench did not match the power levels observed in the truck. After this time and effort we decided to stop the development work. At this time we can test the injectors, but cannot quantify good from bad with high confidence. Rather than conducting further development "on the back" of the customer and risk getting a "black eye", we do not test them. We recommend you strongly question any company that can promise accurate testing of these injectors. In our opinion, if the diagnostics on the truck say it's bad, it probably is.

14) Do I need to replace my High Pressure cross feed tubes when I replace my Cummins injectors?

We re-use the same high pressure feed tube on our test bench. However, if it leaks on our bench it is easy to spot and fix. For an engine, at a minimum, careful inspection of the end of the feed tube is necessary. If there is any scratch, ding, dent or other signs of damage replace it. If you suspect the system may have been contaminated with debris or water, replace them all. There is no way to be sure you have cleaned the inside of the tube with the edge filter in place. If you choose to remove the edge filter (see question 15) and run the system without it, then the tube can obviously be cleaned. We do not recommend the removal of any edge filter unless you are prepared to rebuild the engine when a piece of debris gets lodged in the injector control system and holds it open, dumping as much fuel as the pump(s) can put out in the meantime. "Official" Cummins, Bosch or Dodge recommendation is to replace all feed tubes when the injectors are removed. Some shops always replace the tubes as they have been "burned" too many times with leaking tubes and have had to redo the job. The choice is yours.

15) Can I remove the injector edge filter for better flow?

The injector output is incrementally increased by removal of the edge filters, but in our opinion the cost of the smallest piece of debris locking the injector open is not worth the small gain. Better to properly size the nozzle to hit your desired fuel level. We have the tools to properly disassemble the high pressure fittings and re-crimp the locking collar, but we do it only under direct customer order and after they have been warned of the possible consequences.

16) What about extra filtration?

Typical stock filters are rated at 5 micron and are sufficient for stock applications when serviced at proper intervals. For higher output, and higher flow, staged filtration as used extensively in the heavy duty diesel world is best. A 10 micron primary filter followed by a 5, or even 2 micron, secondary filter is recommended. End use and geography comes into play as well. In northern climes fuel waxing must be taken into consideration with lower micron rated filters subject to quicker plugging with gelled fuel.

As a rough guideline, the filter package should be able to flow 150 Gallons per hour without generating excessive backpressure for each CP3 pump (stock or modified). This assumes each one is being fully utilized. If not, lower supply flow may be acceptable.

17) I have nozzles from someone else and want to find out what they flow. Can you do that and what is the cost?

We can baseline flow your nozzles if you send them in without the injectors. Do not clean them other than spray them off with solvent and bag individually keeping the needles and bodies together. They are match ground to each other, and cannot be mixed. Do not attempt to wire brush the nozzles as it will destroy them. Cost to determine flow is $20 per nozzle which includes cleaning and flow testing to industry standard and a summary sheet for the set.

18) My balance rates are off, what can I do?

Balance rates are an indicator of how evenly each cylinder is accelerating the crankshaft. Anything that affects cylinder firing "strength" will affect the balance rate readings. We have heard of normal things, such as valve lash and low cyl compression (copper seal, loose injector cup - LB7, rings, head gasket...) affecting balance rates. We have also seen a few unusual things such as bent connecting rods causing high balance rates as well. So there are a number of things besides injectors affecting balance rates, and those should be eliminated as possible contributors before removing the injectors.

To help determine if the root cause is related to the injectors, or one of the other items mentioned above, exchange the injector in the questionable cylinder with one from another cylinder. If the excessive balance rate does not follow the injector to its new position, begin checking the engine related items listed above. If the balance rate does follow the injector, the injector needs to be repaired (if possible), or replaced.

When installing a set of modified injectors in an engine that is equipped with injector output codes (NIMA codes), it sometimes helps to set all of the cylinder codes to the same value. Once modified the injector likely no longer has the output characteristics that are mapped in the factory NIMA code. Since we already have balanced the injectors on the bench, it is best to have the ECU treat them all the same rather than try to compensate for an output characteristic (high or low) that is no longer there.

19) Do you modify the latest Piezo injectors for the 6.7 Ford and the LML Duramax?

Yes, we can increase the injector output of the latest Piezo injectors. We have completed our test program for these modifications and are moving forward with several injector sets to assure excellent set balance and consistency. E-mail us through the contact link for the latest status.