N55 Fuel Injector Replacement

Figure 1One used EU5 injector, Bosch label side. From our bench.

The N55 sprays fuel straight into the cylinders through Bosch solenoid injectors. First find out whether it's the injector, the coil or the plug, then which injector your car takes. The N54's piezo injectors are a different job: see the N54 injector guide.

Injector, coil or plug?

A misfire code names a cylinder, not a part. Shop rules of thumb, not BMW's:

  • Coil swap test. Ignition off, swap the dead cylinder's coil with a neighbor's, clear the codes with a scan tool, drive. Misfire moved: it's the coil. Stayed: swap the plug the same way. Still there: suspect the injector.
    Figure 2A coil, with the rubber boot end circled: the end that goes down into the plug well. From our bench.
  • Wet plug check. Pull that cylinder's plug and compare it with the others. Wet, sooty or carboned points at that injector, but isn't proof.
    Figure 3Rust on the metal sleeve of a coil pulled at 185,000 miles. From our bench.

BMW: on N55 cars built up to 31 January 2015 (F30 and F34 unconfirmed: send us your VIN), injector circuit codes (a short, a slow current rise, a broken wire) can be a fault inside the engine computer. Don't buy injectors for those: check the wiring, connectors and power from the power distribution module first.

Which injector? Two questions

Unsure of your chassis code (E70, F10 and so on)? Send us your VIN.

1. Which hold-down (the bracket that clamps the injectors in). BMW built the N55 two ways. Easiest check (BMW's own test): do map steps 1 to 4 below (battery off, wells vacuumed, covers and coils off) and look straight down. An EMC plate (a heat shield) over the injectors means the bottom version. Brackets on top of the injectors mean the top version. BMW also splits them by engine number, not build date: bottom up to 14407684 (E70 and E71: up to 02167648), top from 14407685 (E70 and E71: from 02167649). BMW doesn't allow mixing the two versions' injectors, hold-downs, plug shafts, heads or screws.

2. Which emission type. EU5 and EU6 are emission standards: a separate split, and a different injector.

EU5 or EU6Before you order, read the number printed on the installed injector (BMW uses a borescope, a small camera on a cable), or run the injector check in BMW's diagnosis software, which says EU5 or EU6.

Owner's note, not BMW's: the labels differ. Of two used EU5 injectors on our bench, one carries the BMW roundel and the BMW number 13 64 7 597 870, and the other shows only Bosch's number, 0 261 500 109. So a label can carry either one. Use the scan tool check or send us a label photo.

BMW says its parts catalog has injector number errors, so these lists are a guide, not proof.

EU5 onlyE70, E71, E82, E84, E88, E90, E92, E93.
Either: check yoursF01, F02, F06, F07, F10, F12, F13, F15, F25, F33, F36, and the F30 built before 1 July 2013.
EU6 onlyF32, F34, F26, F16, F23, F87, the F22 M235i (the xDrive can be either) and the F30 built from 1 July 2013.

Mix EU5 and EU6? Shop rule of thumb, not BMW's: one type on the whole engine, the type your car needs.

The parts

EU5 injector, bottom versionBMW 13 53 7 568 607Parts sites match it to Bosch 0 261 500 063.EU5 injector $195.99 →
EU5 injector, top versionBMW 13 64 7 597 870One parts site matches it to Bosch 0 261 500 109. Send us your VIN.
EU6 injectorBMW 13 64 8 625 397Replaces 13 64 7 645 960.EU6 injector $118.99 →
Decoupling elementBMW 13 53 7 577 649The small part on the injector's shoulder. New every time an injector comes out, one per injector.
Genuine $18.99 →IA EURO $10.99 →
PTFE seal ringBMW 13 53 7 591 006The Teflon ring on the injector tip. New injectors come with one. A reused injector needs a new ring.
Clamping plateBMW 13 53 7 584 676Bottom version only. New every time.
Ignition coilBMW 12 13 8 616 153Delphi, six per car, the same on every US N55.Coil $42.99 →
Figure 4The two high pressure lines run from the rail down to the injectors. Generic layout: yours may differ.

Tools

Scan toolReads and clears codes, runs BMW's injector check and the coding. BMW's diagnosis software does; a vendor says Autel's MX808 and AP200 can code (untested by us).
Seal ring setOnly for a reused injector. BMW's: pliers 13 0 191 (now 2 45 2959), cone 13 0 283, fitting aid 13 0 281 and sizer 13 0 282 (those two come only in kit 13 0 280). Substitutes: aftermarket kits exist (untried by us); make sure the listing says N55.
Injector pullerBMW's 13 0 270 (bottom version, square drive) or 13 0 320 (top version, hex drive, left-hand pull-out thread), plus crow foot 00 9 170 (24 mm) for the torque wrench. A vendor sells the CTA 7658 as comparable to the 13 0 320; no copy of the 13 0 270 found. No slide hammers, pry bars or power tools: BMW says they can damage the head and the injector.
AlsoLine wrench set 13 0 160 (with 13 0 161 and 13 0 162) for the line nuts, plug set 32 1 270 to cap open lines, a torque wrench, transmission oil, a borescope, a vacuum, compressed air.
Fuel under pressure. The rail runs about 50 bar at idle and up to about 200 bar at full load, and BMW gives no wait time to let it drop. Ventilate the bay. No flame, sparks or smoking. Coolant below 40 °C (104 °F) before you touch the fuel system. Face guard and gloves: fuel can shoot out of an injector on its own. The fuel pump starts by itself when a door opens. Disconnect the battery negative first (short-circuit fire risk; on the F10 the battery is under the luggage compartment floor). Catch escaping fuel.
ActiveHybrid 3, 5 and 7 are high-voltage cars. BMW's job opens with a danger-to-life warning and hybrid safety steps we don't repeat here: don't start without them. Also disconnect the auxiliary battery's negative terminal.

Out in this order

  1. Cool, battery off
  2. Clean the wells
  3. Covers offF10: acoustic cover, intake silencer housing, clean air pipe. E70: engine cover, intake port, silencer housing, clean air pipe, rear coil cover. Others: not listed; take off whatever covers the coils and send us your VIN.
  4. Coils out
  5. Pressure line
  6. Connector, ground cable
  7. EMC plateBottom version only.new clamping plate
  8. Hold-down
  9. The injectornew decoupling elementnew PTFE ring if reused

Torque

Hold-down bolts13 Nm
High pressure line nuts, both ends23 Nm, threads coated with transmission oil
Coil ground cable nut5 Nm
EMC plate screws, bottom version8.5 Nm (screw plug in the plate: 25 Nm)
Twisting an injector to align or pull6 Nm at most

Lines can go back on up to 10 times (BMW).

Out

  1. Map steps 1 to 4: cool, battery off, injector wells (where the injectors sit) vacuumed, covers and coils off (pull each coil straight up, slowly, and never oil or grease the boot: it's talc-coated). Move the cable channel and oxygen sensor connector if they block you. BMW says fuel on a coil boot can kill the coil: cloth in every plug well, and replace any coil that got wet.
    Figure 5Engine top with the cover off: the cable channel runs along the back. Generic layout: yours may differ.
    Figure 6A connector block on its bracket. Generic layout: yours may differ.
  2. Pressure line off. Rag over the injector. BMW relieves the pressure by tapping the injector carefully with a wrench. Loosen the line nuts, rail end (the fuel pipe the lines run from) first, then injector end, and take the line off. Mark each line, cap both ends. Lines fixed to the rail? BMW's older page takes the rail off instead: send us your VIN.
    Figure 7The two high pressure lines run from the rail down to the injectors. Generic layout: yours may differ.
    Figure 8One high pressure line running across the coil cover. Generic layout: yours may differ.
  3. Connectors and ground cable. Unlock each injector connector and pull it off. Undo the nut, take off the coil ground cable.
    Figure 9Releasing a connector with its locking lever. Generic layout: yours may differ.
  4. Bottom version: EMC plate. Screw plug out, plate screws loose. Lift off the clamping plate (scrap it), the counter support and the EMC plate.
    Figure 10The injector area with the coils out. The marked metal plate is the EMC plate on a bottom version. Generic layout: yours may differ.
  5. Hold-down off. Top version: screw 2 first, then screw 1, or it can tilt. Bottom version: loosen its bolt, feed the bracket out.
    Figure 11The hold-down plate over the injectors. Generic layout: yours may differ.
  6. Injector straight up. Tape its cylinder number on it, cap the tip and line port, toss the decoupling element.
    Figure 12The tip of one used injector, with burnt carbon on the tip. From our bench.
    Figure 13The decoupling element on the injector's shoulder. It always gets thrown away. Generic layout: yours may differ.
  7. Stuck? Puller on the injector well, left-hand thread oiled, sleeves screwed onto the injectors, puller screws 8.5 Nm. Torque wrench on the puller at 13 Nm (BMW's setting for its own puller, 2000 N limit; we can't vouch for a copy), clockwise, until the injector comes out. A click means scrap the injector.

In

  1. Read the code value first. Find the three-digit number on each injector going in, on its body (not the long Bosch number, not the old injector's). Shop experience, not BMW's: on our injectors it sits at the end farthest from the nozzle, the fuel line end. On the Bosch-labelled one it is the last three digits of the label line. Write it down with the cylinder it goes into. You enter it in step 8.
    Figure 14Two used EU5 injectors. One label carries the BMW number, the other only Bosch's. The circled 3-digit number on the Bosch one is the coding value. From our bench.
  2. Seals. New decoupling element. A new injector already has its ring: leave its cap on until it goes in. A reused one needs a new PTFE ring, fitted with oil-free hands: pliers take the old ring off, a fluff-free cloth wipes carbon off the round part of the tip (never the tip face), then cone, fitting aid, sizer. No fingernails, no lubricant. Install within 10 minutes of fitting the ring, or cap it: it swells.
    Figure 15The decoupling element on the shoulder, and the PTFE tip ring below it. Generic layout: yours may differ.
  3. Injectors into the bores. Fit the puller, turn the wrench counter-clockwise to 2 Nm. Bottom version: keep the puller's pin off the head cover.
  4. Hold-down on, hand-tight. Top version: curved side down, screw 1 by hand, screw 2 only a few turns. Bottom version: bolt hand-tight so the injector still turns, align them (6 Nm at most; BMW's pages differ), then EMC plate, counter support and a new clamping plate, screws hand-tight.
  5. Lines on with the rubber damper, threads coated with transmission oil, nuts by hand only, until both thread on with no strain. A nut won't start? Don't force it. BMW's fix: back off the neighboring line nuts and the hold-down screws, fit the line hand-tight, then re-tighten them all.
    Figure 16The high pressure end of an injector: hex nut, thread and sealing cone. From our bench.
    Figure 17A high pressure line off the engine, with its fittings. Generic layout: yours may differ.
  6. Torque it. Hold-down 13 Nm (top: screw 1 then 2. Bottom: through the EMC plate, then plate screws 8.5 Nm and screw plug 25 Nm). Lines 23 Nm. Bottom version: injector end first, then rail end. Top version: BMW's pages disagree on the order, so we give none.
  7. Connectors on until they click, ground cable back on (nut 5 Nm).
    Figure 18An injector connector locked onto an injector. Generic layout: yours may differ.
  8. Battery on, code the injectors. In BMW's diagnosis software: Service functions, Engine electronics, Adjustment functions, injection quantity compensation. Enter each noted value for its cylinder. Shop experience, not BMW's: a Foxwell-type scan tool can enter it too.
  9. Finish. Blow the plug wells clean (compressed air), coils on and pushed to the stop (the rubber cap must wrap the whole sealing collar), covers on, check for fuel leaks, clear the fault memory, start it. Rough or no start? Check the coding.
    Figure 19End-on view of a coil's rubber boot, the end that sits down in the plug well. From our bench.

Code every injector you install

BMW calls it injection quantity compensation. Each N55 injector has a three-digit calibration value on its body that the engine computer uses for that cylinder's fuel quantity. BMW requires the coding whenever an injector is replaced or moved to another cylinder, or the engine computer is replaced. Skip it and the engine can run rough or not start. Forum posters say EU6 needs none; BMW says otherwise. Follow BMW.

Where people mess it up

  • Ordering by catalog alone. A wrong injector gives a warning lamp, mixture faults and a rough idle (BMW).
  • Reusing a decoupling element or PTFE ring. BMW says it can cause line breaks and fuel discharge.
  • Following an N54 or N20 write-up. Different coding (N54), different rail layout (N20 and N26).

Steps, torque values and part rules come from BMW's repair instructions for the injectors, high pressure lines and ignition coils and BMW's US service bulletins on N55 injectors, with owner and parts site notes labeled. Part numbers come from BMW's parts catalog up to 2020. Check yours by VIN.

Read the full guide free

Two quick answers and the rest of the steps open. We use them to pick the next guides and the parts we hunt deals on.

You'll get new guides by email. Unsubscribe anytime. Have an account? Sign in.

Now find the part.

Search by chassis or engine, or browse the whole catalog

Shop your BMW All parts