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Injector Removal and Installation

Please review this page when removing injectors whether you are shipping them to us for overhaul, or for those using our HotSwap program this will assist you during the installation process.


NOTE: When sending injectors to us for overhaul (or those returning cores) Remove and Re-use the #3 injector return fitting which is easily removed using a 10mm socket/wrench. The fitting uses two copper seals that can be re-used upon re-installation. The tightening torque is measured by securing hand tight and then rotating 1/8th of a turn. Use caution to NOT use excessive torque or you may deform the copper seals and this can result in fuel leaks at the fitting.

When you are selecting the “I’ll be sending in my injectors for overhaul” option, we have twice daily FedEx and USPS pickup and  delivery, and once daily UPS delivery options.

Ship your injectors when sending us your cores for overhaul marked:

DBW LLC
ATTN: (your last name) – DBW INJECTOR OVERHAUL
5737 S Graphite Way
Meridian ID, 83642
USA

Phone if required for shipping contact: (208) 863-7496

NOTES for Packaging your injectors:

VE TDI Injectors: Please package so that they are wrapped so as not to move around loosely in the package. MAKE ABSOLUTELY sure the #3 wire is protected, we strongly suggest this injector be wrapped separate from the other 3 (or 4 in some cases) so that the wire is not damaged at the junction to the body. Shipping insurance WILL NOT cover injector damage, and if we discover any damage upon receipt we will notify you with photographs and documentation as received.

After wrapping in paper towel, place in a gallon sized zip-lock bag, this will prevent any fuel from leaking and causing issues during shipping.

PD TDI Injectors: Wrap these individually with paper towel, be sure the plastic connector is protected and use a single piece of bubble wrap or some other shock protective packaging. Place the individually wrapped injectors in a box with some additional protective wrapping, again to be sure they don’t hit against each other during shipping. Damaged wiring connectors can be replaced, but this solenoid repair is approx $150 due to the rarity of these parts… Be thorough when shipping these to insure they are well protected.

Common Rail Injectors: Just like the PD injectors, wrap them individually, and be certain to protect the upper plastic portion of the injector from damage. This cannot be repaired if broken!


Removal and Installation Guide: DBW Injector And Removal Guide

CAUTION: Debris 1/100th the size of this ” . ” will damage an injector nozzle, Sterile operating practices cannot be over-emphasized! We use Sterile fluids and ultrasonic cleaning and we functional check EVERY injector before leaving our shop.


Okay, now lets get to dialing in your injectors!

Once you have completed the Removal and Installation DO NOT drive the car until the following steps are completed. Excess smoke, poor fuel economy or in some cases engine/turbo damage MAY occur!

You will require the use of VCDS to read the values from the ECU for:

  1. Injection Quantity
  2. Injection Timing.

STEP 1: Setting Injection Quantity (IQ)

Injection Quantity Adjustment Procedure

Because the injection pump cannot directly measure fuel quantity delivery, these values are therefore derived by monitoring the crank position sensor and computing actual crank acceleration values between the teeth of the sensor wheel. These values are converted into equivalent fuel delivered and displayed by the ECU in the Group 13 data.

NOTE: Since crank acceleration is used, normal variations in compression from cylinder to cylinder can cause variations in the group 13 value for each cylinder. Although the injectors are flowing identical, the combustion pressure generated will vary if a cylinder is higher or lower on compression…So you can expect to see some variation from cylinder to Cylinder in respect to these values.

WARNING: Gross deviations can be a sign of contamination introduced to the injector during install, if you see a variation of more than 1.0 for any cylinder in group 13,  STOP the engine and contact us so we can prevent damage to the new injector.

When setting the IQ value, keep in mind the following which is OPPOSITE what you may think:

  1. a HIGHER IQ value results in LESS fuel delivery
  2. a LOWER IQ value results in MORE fuel delivery

Adjusting the IQ value is required due to how the pump functions, without getting into specifics, the following values will help you get your car dialed in with the least hassle and get you on the road with a perfectly running car.

NOTE: An IQ value of 2.8 or less causes a Smooth Idle Control Conflict, this will not harm the pump or the engine, it just makes it difficult for the ECU to smoothly control the cars return to idle during deceleration and when the engine resumes IDLE rpm at any other time. If set below 2.8 you may notice a momentary “chugging” as the engine stabilizes at Idle RPM.

** A Maximum IQ value of 9.0 insures that Starting is within reasonable response times.
*** As IQ values increase above 2.8, this causes an commensurate increase in the period of time (1/10 of a second) for the engine to start. This slight increased delay in starting is simply the result of the pump going from ZERO fuel delivery to the point that fuel delivery can commence at the injector. Experience has shown that when going above IQ values of 6.0 or higher, only does this slight delay become more pronounced. Again there is no risk to the engine or pump, only that the delay is NORMAL and due to injection pump function.

To alleviate this delay, we try to set the flow range of the injectors so that the pump operates in the 2.8-6.0 range for the ECU IQ value. This insures the fastest starting, lowest smoke, and most efficient fuel delivery for your application. However due to variations from one injection pump to another its impossible to match our settings to the variables associated with your specific injection pump, THUS some variation is to be expected with your specific pump and the settings applied to your set of injectors.

Start with the values below, we suggest adjusting the IQ value UP or DOWN as needed so that you get a “Light Haze” under full throttle in 3rd gear, this simply indicates where the engine is getting the best power, and cleanest combustion.

NOTE: REMOVE ALL ELECTRONIC CORRECTIONS IN ADAPTATION, This should be set to “32768” before proceeding. All changes should be made MECHANICALLY, and then after that you can use the Adaptation for small “trim” or fine corrections.

Stock range nozzles (DLC 706, DLC 520, Power Plus 520) start with IQ values of:
2.8 to 4.0

Performance Range Nozzles (DLC 1019, DLC 764, Power Plus 764) start with an IQ Value of:
5.0 – 7.0

Race Range Nozzles (Race 520, PowerPlus 767-7X, Race 520 7X)
5.0-7.0


Step 2: Injection Timing

DBW Injection Pump Timing Procedure

So why does injection timing change? Well simple the Injection pump has NO direct reading of injection timing! The pump is a simple mechanical unit that pumps fuel based on a fixed point of rotation. No matter what this pump will start pushing fuel at the same time, every time!

The ECU can control this Start of Injection (SOI) electronically, but when setting the injection timing we SHUT THIS OFF to measure that exact mechanical moment that the pump wants to begin injecting fuel.

By doing this we measure YOUR pumps interaction with the NEW injectors!

Your old injectors had a COMPLETELY different response to the injection pumps output, therefore with the new injectors THIS WILL CHANGE, in most cases significantly!

Experience shows that the injection pumps relationship with new injectors will result in RETARDING (later delivery) of the fuel. This causes poor or slow starting, no starting during cold temperatures, higher EGT’s, increased smoking. This is NOT good for your engine, the environment or your pocket book since fuel consumption increases and you are wasting fuel!

The link above includes all the details needed for you to get your car adjusted.

NOTE: VCDS and Ross-Tech are constantly updating their software, please refer to their website for VCDS specific questions when accessing IQ, Timing and other related fields.

VCDS Practice/Demo

Thank you and we hope this helps you with your new injectors!

The Staff at DBW LLC

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