Short answer: The B58's high-pressure fuel pump (HPFP) bolts to the back of the valve cover, by the firewall. You disconnect the battery, bleed off the pressure by slowly cracking the 17 mm line nuts into rags, then remove the lines, the plug and the T30 pump bolts. A Dorch pump goes on a flange you center with an alignment tool: 12 Nm with blue threadlocker for the flange and pump bolts, 31 Nm for the high-pressure line nuts. Gen 1 cars (200 bar) need the cowl, strut bar and firewall shroud out first. On a Gen 2 G20 (350 bar), Dorch only moves covers and a harness bracket. Load a tune that supports the pump before the first start, and expect to crank a few times, or bleed the line by hand, before it fires.
I'm Gleb Blekher. I run B58 Racing out of Dallas, TX. The HPFP is the first real fuel upgrade on most tuned B58s, and my own 540i runs a Gen 1 Dorch pump. Dorch publishes the most complete instructions of the pump makers we carry, for both generations, with torque values. So this guide follows Dorch's two install sheets, with notes from Spool and Bosch where they publish anything. Where I couldn't confirm a step or a torque value, I say so.
Who this guide is for, and which pump fits your car
The B58 comes in two fuel systems, and the pumps don't swap between them. Gen 1 runs about 200 bar of direct-injection pressure. Gen 2 (B58TU) runs 350 bar. Not sure which engine you have? Read our B58 Gen 1 vs Gen 2 guide first.
| Engine | Cars | Pumps we carry that fit |
|---|---|---|
| Gen 1 B58 (200 bar) | M140i (F20), M240i (F22), 340i (F30), 440i (F32), and the 540i (G30), 640i GT (G32), 740i (G11) and X3/X4 M40i (G01/G02) through the 2019 model year | Dorch DS25 Gen 1, Dorch DS3 Gen 1, Spool FX-200 Gen 1, Spool FX-350 Gen 1, Bosch B58TU pump with the Gen 1 extension harness |
| Gen 2 B58TU, BMW (350 bar) | M240i (G42), M340i (G20), M440i (G22), Z4 M40i (G29), 840i, X5/X6/X7 40i, and the 540i, 740i and X3/X4 M40i from 2020 on | Dorch DS25 Gen 2, Dorch DS3 Gen 2, Spool FX-350 Gen 2, Bosch B58TU pump (factory replacement) |
| GR Supra 3.0 (350 bar) | A90/A91 | Dorch DS25 Gen 2, Dorch DS3 Gen 2, Spool FX-350 Supra, Bosch B58TU pump (factory replacement) |
- The Bosch B58TU pump (BMW 13518631642) is the factory Gen 2 pump. On Gen 1 it's a popular upgrade because it flows more than the original pump, and it uses an extension harness.
- Dorch and Spool pumps replace the factory pump in the same spot, with their own lines and adapter harness. Both brands say a tune change is required.
- S58 owners: the M2, M3, M4, X3 M and X4 M run two pumps and aren't covered here. See the Spool FX-350 for the S58.
Not sure you need a pump yet? Our B58 fueling guide covers when the stock HPFP runs out.
Safety first: pressure, fire and the coil packs
- The system can be under very high pressure. Dorch warns the pump can be under extreme pressure even with the engine off. Bleed it off slowly, as described below.
- Disconnect the battery's ground terminal first. Both Dorch sheets start there. Dorch also warns that once it's reconnected, the in-tank pump primes as soon as the driver's door handle is touched, so have every fitting tight first.
- Fire risk. Work on a cold engine in a ventilated space, with no sparks or flames nearby and a fire extinguisher rated for fuel fires in reach.
- Protect the coil packs. Dorch says fuel on the coils' silicone boots can lead to coil failure, and that BMW advises covering them when you open the fuel system.
- Safety glasses, gloves and plenty of rags or absorbent pads under the fittings.
- Keep it clean. Dorch says all HPFPs are very sensitive to contamination. Clean around the pump before you pull it.
If you aren't comfortable opening a pressurized fuel system, have a shop do this one.
Difficulty and time
- Gen 1: about 3 out of 5. Most of the work is getting to the pump through the cowl, strut bar and firewall shroud.
- Gen 2: about 2 out of 5. Dorch's G20 procedure leaves the cowl alone.
- Time: we couldn't find a brand time estimate, so I won't guess. Allow extra time for bleeding the line on first start.
- No lift needed. It's all done from the top of the engine bay.
Tools
These are the tools named in Dorch's two install sheets.
- 17 mm wrench (and a 17 mm crow's foot to torque the line nuts).
- Torque wrench that reads 12 Nm and 31 Nm.
- T30 Torx socket for the pump and flange bolts.
- E6 external Torx socket for the line bracket bolts.
- 5 mm Allen for the pump-to-flange bolts (Dorch Gen 2).
- Gen 1 only: 10 mm socket for the cowl fasteners and firewall shroud, and E18 external Torx for the strut bar.
- Gen 2 only: 19 mm crow's foot for the low-pressure collar nut and a 13 mm socket for the rear cover barb.
- Aluminum AN wrenches, which Dorch recommends so you don't mar the fittings.
- Blue threadlocker, a little clean engine oil, rags, gloves and safety glasses.
Parts list
- The pump kit for your generation. Dorch kits include the pump and hardware, a Dorch high-pressure line and a plug-and-play adapter harness. Gen 2 kits add a low-pressure hose and bracket, and Gen 1 kits an engine cover spacer.
- Flange alignment tool. It comes in the kit. If yours is missing, we sell the Dorch HPFP alignment tool on its own.
- Spare Dorch parts for a used kit or a dropped part: pump and flange bolts, the HPFP O-ring, the low-pressure hose bracket and collar nuts. These fit Dorch pumps only.
- Pump gasket. Dorch says the factory gasket can almost always be reused. If yours is damaged, Hack Engineering lists BMW part 11128633750.
- Running a flex fuel (ethanol) sensor? Use Dorch's ECA-fitment hose: Gen 1 or Gen 2 and Supra. Standard replacement hoses: Gen 1, Gen 2 and Supra. A 5/16 in factory line joins a 3/8 in sensor with an SAE quick-disconnect adapter.
- A tune that supports the pump, ready before the first start.
Plan the low-pressure side too. Spool says the HPFP relies on fuel for lubrication, that low-side starvation can damage the piston and bore, and that FX-350 buyers should run an upgraded low-pressure pump. Options we carry: Spool Stage 3 LPFP for F-series Gen 1, the G30 540i, Gen 2 BMW and the GR Supra, or the PFS drop-in LPFP for the Supra and Gen 2 G-series cars.
Gen 1 install: F-chassis and 2017–2019 G-chassis (Dorch DS25 / DS3)
These steps follow Dorch's current Gen 1 install sheet. Dorch wrote it on an F30, and says the cowl and strut bar may differ slightly on other models.
Getting to the pump
- Disconnect the battery's ground terminal and remove the engine cover.
- Remove the cowl covers. Each side is held by three 10 mm quarter-turn fasteners. Turn them a quarter turn to the left, lift each cover by its outer edge (toward the fender), then slide it out to the side.
- Remove the cowl weatherstrip. Pull the wire out of its groove first, then pull the strip toward the front of the car.
- Remove the DME (ECU) cover. Unclip the coolant line, then pull the cover straight up.
- Remove the left strut tower cover clip. Pull up the center, then remove the whole clip. This exposes a strut bar bolt.
- Pop out the two black round covers under the cowl that hide the other strut bar bolts. Push them out from underneath, with a hand over the top so they don't fly off and get lost.
- Remove the strut bar. Loosen all four E18 bolts and lift it out.
- Remove the upper firewall shroud. It's held by seven 10 mm bolts, four on the left and three on the right. Take out the shroud and the foam sound insulation behind the engine. The pump is now in reach.
Removing the factory pump
- Cover the coil packs, then bleed off the pressure. Put absorbent pads under both the inlet and outlet of the pump. With a 17 mm wrench, slowly crack the outlet nut, then the inlet nut. Open them just enough to drain, not enough to spray. Dorch says to let them drain for a couple of minutes before removing any nut completely, even if you think it's already drained.
- Unplug the pump while it drains. Pull the gray tab out until it stops (toward the front of the car). Then push the gray tab in toward the connector body while you pull the connector off the pump.
- Remove the hold-down bracket bolts on the low-pressure and high-pressure lines with an E6 socket. Keep the low-pressure line bracket, since you'll refit it later.
- Remove the high-pressure line. Don't let fuel drip onto the coil pack boots.
- Remove the pump with a T30 socket. Back the two bolts out a little at a time, alternating, so the pump comes out straight. The area must be very clean. Inspect the gasket. Dorch says it can almost always be reused.
Fitting the Dorch pump
- Install the Dorch flange. Use the supplied T30 bolts with blue threadlocker. Press the alignment tool into the center of the flange, then tighten the bolts. Torque: 12 Nm, blue threadlocker required.
- Remove the alignment tool and fit the pump into the threaded holes Dorch shows in its sheet. Tighten the bolts evenly. Dorch warns that uneven loading on the pump's spring can damage the pump. Torque: 12 Nm, blue threadlocker required.
- Reconnect the factory low-pressure hard line to the Dorch pump. Position it so it doesn't touch the coil pack connector, then tighten the nut with a 17 mm wrench. Dorch doesn't give a torque value for this nut.
- Refit the low-pressure line bracket. Adjust it to suit the line, then tighten it back down in its original spot with the E6 socket.
- Fit Dorch's two-piece high-pressure line. Install the larger U-shaped line onto the fuel rails first, finger-tight at most. Then thread the pump connection on finger-tight. Every nut must thread on easily by hand and bottom out, with each line end sitting roughly centered in its nut. If one fights you, fix the alignment instead of forcing it. Once everything lines up, tighten the nuts in the numbered order shown in Dorch's sheet.
- Torque the high-pressure nuts. Put a little oil on the threads to prevent galling. Torque: 31 Nm. Dorch says that if you don't have a crow's foot, just snug the nuts with a 17 mm wrench, and warns that 31 Nm is not a lot of torque, so don't overtighten and damage the line.
- Plug in the supplied adapter harness.
Older Dorch Gen 1 kits (side-inlet pumps) used a Dorch low-pressure hose and a one-piece high-pressure line instead of steps 16 to 18. Follow the sheet that came with your kit.
Gen 2 install: B58TU BMW and GR Supra (Dorch DS25 / DS3)
These steps follow Dorch's Gen 2 install sheet, which is based on a G20 M340i. Dorch says the cowl and hoses may differ slightly on other models. I couldn't find a Supra-specific procedure from Dorch, Spool or Toyota, so Supra owners should expect some differences in the covers and hose routing.
Removing the factory pump
- Disconnect the battery's ground terminal (in the trunk on the G20). Remove the engine cover and the DME cover.
- Remove the wiring harness bracket over the high-pressure line. Push its two tabs outward to release them. Lift the harness straight up and lay it to the side.
- Unplug the pump. Pull the gray tab out until it stops. Then push it in toward the connector body while you pull the connector off.
- Move the rear insulation covers. Release the two rubber snaps by pulling them upward carefully, then push the covers back toward the firewall.
- Remove the low-pressure line fastener on the valve cover with an E6 socket.
- Cover the coil packs and bleed the high-pressure side. Put a pad under the pump outlet. Slowly crack the 17 mm outlet nut, just enough to drain without spraying. Dorch says to let it drain for a minute or so before you remove any nut completely. Then remove the high-pressure line.
- Bleed the low-pressure side. Move your rag to the pump's low-pressure port and crack the 17 mm nut there too.
- Remove the factory low-pressure hose in one piece. At the junction next to the DME, slide the gray locking clip off sideways (use two hands so you don't drop it). Push the black release collar up into the fitting while you pull the hose up. Have a rag ready. Guide the hose out under the rear firewall covers.
- Remove the pump with a T30 socket, a little at a time on each bolt so it comes out straight. Keep the area very clean, and inspect the gasket.
Fitting the Dorch pump
- Install the Dorch flange with the supplied T30 bolts, the alignment tool pressed into its center. Torque: 12 Nm, blue threadlocker required.
- Remove the alignment tool and fit the pump. Tighten the 5 mm Allen bolts evenly. Dorch says that if the pump doesn't slide in nicely, the flange is misaligned and you should redo step 10. Torque: 12 Nm, blue threadlocker required.
- Fit the high-pressure line. It goes into the rear-most fuel rail port first, then rocks over into the pump port, and finally pulls down and back into the front-most rail port. Dorch says it's a tight fit, and the line must sit as straight as possible. Dorch test-fits every line before shipping. If it doesn't line up, slightly loosen the pump-to-flange bolts and rotate the pump in its bolt holes. For more adjustment, do the same with the flange-to-valve-cover bolts. Re-torque anything you loosened.
- Torque the three high-pressure nuts once they thread on easily and bottom out. Torque: 31 Nm. As with Gen 1, Dorch says snugging them with a 17 mm wrench is fine if you can't get a torque wrench on them. Don't overtighten.
- Plug in the Dorch adapter harness. Once it clicks in, push down the gray locking tab on the engine harness.
- Connect the Dorch low-pressure hose at the car's feed line. Take the blue collar nut off the hose. Slide the hose down onto the car's low-pressure line, then thread the collar nut in. Dorch recommends a small drop of blue threadlocker on it, and says to use two hands because these nuts are easy to drop into the engine bay. Snug it with a 19 mm crow's foot while you hold the fitting straight.
- Route the hose behind the intake manifold, like the factory hose, and thread it onto the pump finger-tight. Remove the rear cover hold-down barb with a 13 mm socket and refit it with the Dorch hose bracket.
- Tighten the AN fitting on the pump. Dorch doesn't give a torque value here. It uses the "flats" method: finger-tight, then 1 to 1.5 more flats of the hex with a wrench. Hold the hose at the angle you want while you tighten.
Spool and Bosch pumps: what we could and couldn't confirm
Spool FX-200 and FX-350. We couldn't find a published step-by-step install sheet from Spool. Spool calls the pumps plug-and-play, with no cutting or splicing. The Gen 2 and Supra FX-350 kits include a mounting bracket, an alignment tool, a low-pressure line and an adapter harness, so expect the same flange-and-alignment-tool approach as above. The Gen 1 pumps come with a choice of modifying your existing high-pressure line or adding Spool's stainless line. Spool says the tune changes must be applied before the first start, to prevent damage and avoid voiding the warranty. Use the instructions and torque values in your Spool kit.
Bosch B58TU pump (13518631642). On a Gen 2 car or Supra, it's the factory part, so follow the removal steps above and reverse them. Use a sound gasket and tighten the bolts a little at a time so the pump seats straight. On a Gen 1 car, use the Gen 1 access and bleed-down steps. Hack Engineering says the TU pump's connector faces the wrong way for the older wiring, which is what our extension harness solves. We couldn't find a BMW, Bosch or Toyota torque value we trust for the factory pump bolts or line nuts, so use your car's repair information. A retailer note says BMW treats some high-pressure fuel hardware as single-use, so check before reusing it. Vendors disagree on whether a Gen 1 car needs a tune for the TU pump. Our listing says it does to get the extra flow, and I'd treat it that way.
Priming, first start and what to check after
- Double-check every connection and torque, then reconnect the battery.
- Load the tune first. Dorch says the car will not run with its pump until a supporting tune file is loaded. Spool says its tune changes must be in place before the first start. Tell your tuner exactly which pump you fitted.
- Prime and check for leaks. Dorch's Gen 1 sheet has you switch the ignition on so the low-pressure pump primes the system, then check every connection before cranking.
- Have a helper watch for leaks while you crank and when the engine fires.
- Expect a few cranks. The drained lines and rail are full of air. Dorch says cranking a few times before it fires is normal, and so is a slightly rough idle for a few seconds.
- If it keeps cranking, bleed the line by hand. Dorch says endless cranking from air in the high-pressure line is very common on these engines, even with factory pumps. With rags underneath, crack the nut at the pump outlet, then just slightly at the front fuel rail fitting, until you hear air and fuel bubble out. Retighten and try again. It can take 2 or 3 rounds.
- Still no start? Dorch says it comes down to the supporting tune not being loaded or the line not bleeding.
- Once it runs, recheck every fuel connection for leaks and confirm the pump is torqued down.
- Refit everything. On Gen 1, Dorch strongly recommends refitting the foam insulation over the pump (it may need trimming), because direct-injection pumps are noisy.
- Scan for codes and log a few drives. If fuel pressure falls short of target, check the low-pressure side and the tune before you blame the new pump.
Common mistakes and how to avoid them
- Spinning a line nut off under pressure. Crack it slowly, let it drain, then remove it.
- Fuel on the coil packs. Cover them first and wipe up spills right away.
- Pulling or seating the pump crooked. Work the bolts a little at a time. Dorch warns uneven tightening can damage the pump.
- Skipping the alignment tool. An off-center flange means the pump won't slide in and the line won't line up.
- Forcing or overtightening the high-pressure line. The nuts should thread on by hand. 31 Nm is not much.
- Skipping the threadlocker. Dorch requires blue threadlocker on the flange and pump bolts.
- The wrong hose on a flex fuel car. Order the ECA-fitment hose.
- Starting on the wrong tune, or ignoring the low-pressure side. Both can damage the new pump.
- Mixing up generations. Check the listing against your engine, not just the chassis code.
FAQ
Do I need to remove the cowl to change the B58 HPFP?
On Gen 1, yes. Dorch's F30 steps remove the cowl covers, strut bar and firewall shroud. On a Gen 2 G20, Dorch's steps leave the cowl in place.
What is the torque spec for a B58 HPFP?
For Dorch kits, the flange and pump-to-flange bolts are 12 Nm with blue threadlocker, and the high-pressure line nuts are 31 Nm. We couldn't confirm factory BMW or Toyota values, so use your repair information for a factory or Bosch pump.
Can I reuse the HPFP gasket?
Dorch says the factory gasket can almost always be reused several times. Inspect it and replace it if it's damaged.
Why won't my B58 start after an HPFP install?
Usually it's air in the high-pressure line or a tune that doesn't support the pump. Bleed the line at the pump outlet and front rail fitting, 2 or 3 times if needed, and confirm the right tune is loaded.
Does an upgraded HPFP need a tune?
Yes. Dorch and Spool both say their pumps need tune changes. The Bosch B58TU pump on a Gen 1 car needs a tune to use its extra flow.
Will a Gen 1 HPFP fit a Gen 2 B58 or a Supra?
No. Gen 1 is a 200 bar system. Gen 2 and the Supra are 350 bar.
Going further with fuel? See the B58 fueling guide for injectors, flex fuel and port injection, and shop all fueling parts.
Sources
- Gen 1 access, bleed-down, removal and install steps, torque values (12 Nm flange and pump bolts with blue threadlocker, 31 Nm line nuts), coil pack warning, priming and first start: Dorch Engineering B58 Gen 1 HPFP Kit Installation
- Earlier Gen 1 side-inlet kit steps (Dorch low-pressure hose, -06 AN routing): Dorch Engineering B58 HPFP Kit Installation Rev 2.1 (via a reseller copy at futurez.fi)
- Gen 2 steps on the G20, torque values, 19 mm collar nut, AN "flats" method, manual line bleeding and no-start causes: Dorch Engineering B58 Gen 2 HPFP Kit Installation Rev 1.0
- Dorch kit contents and fitment: Dorch Engineering technical resources and Dorch product information on our listings
- Spool kit contents, tune-before-start and low-pressure supply requirements: Spool Performance FX-350 product pages (spoolperformance.com) and Spool product information on our listings
- B58TU pump connector orientation on Gen 1 and BMW HPFP gasket 11128633750: Hack Engineering B58TU HPFP kit
- Single-use high-pressure fuel hardware note: Turner Motorsport B58 injector kit listing (turnermotorsport.com)
- 200 bar vs 350 bar: BMWTuning.co, B58 HPFP upgrade