PRV Concept
FR / EN
Home/PRV Engines/ZMJ

ZMJ —
from the 604 to the DeLorean

The ZMJ is Peugeot's code for the PRV V6 with Bosch K-Jetronic mechanical injection: 2,664 cc and 144 bhp on the 604 Ti and STI. Its most famous variant never wore a lion: the ZMJ-159, a 2,849 cc of 130 bhp, powers the DeLorean DMC-12 of Back to the Future.

2
DISPLACEMENTS
130–144
BHP
1981
DELOREAN
Mechanical injection

The lion, then the time machine

On the 604 the injected ZMJ succeeds the carburetted ZM: 144 bhp for the Ti and STI, an engine Heuliez carried into the 1982 604 Limousine — the one Philippe Bouvard fitted out as a rolling office, now in the Sochaux museum. Same 2,664 cc block as Renault's Z7V, same K-Jetronic.

Then comes the ZMJ-159: a 2,849 cc with K-Jetronic and Lambda control, 130 bhp SAE net, mounted at the rear of the DeLorean DMC-12. An uneven-firing PRV — the original crankshaft, before offset crankpins — whose workshop manual derives very directly from the Alpine A310 repair guide: the DeLorean did not just receive the Douvrin engine, it received its documentation. The Journal article →

ZMJ
PEUGEOT CODE · 2,664 / 2,849 CC · K-JETRONIC · 12 VALVES
2849
CC · DMC
130
BHP SAE
12
VALVES
Identity

What makes a ZMJ a ZMJ

Figures read in the constructor's documents held in our Library — repair manuals, Pub et Trade data sheets, period bulletins. Nothing here comes from a web fact sheet.

ZMJ 2,664 and 2,849 cc · mechanical injection · 12 valves · first generation DeLorean — specifications →
ZMJ-159
The DeLorean's engine: 2,849 cc, 91 mm bore × 73 mm stroke, 8.8 compression ratio — 130 bhp SAE net at 5,500 rpm, 220 Nm at 2,750, Bosch K-Jetronic injection and Lambda control for the American market. Same displacement as the Volvo B28.
13° · 775
Ignition set at 13° ± 2 before TDC at idle, engine warm; idle at 775 ± 50 rpm, automatic gearbox in “park”. Before timing: vacuum hose disconnected, there must be no vacuum at idle.
3,3 bar
Hot restarting depends on the K-Jetronic's residual pressure: 3.3 bar at rest, still at least 1.7 bar after ten minutes, for injectors that only open at 3.5 bar. The 144 bhp Renault 25 V6 injection (Z7V) asks for the same values.
Guide Alpine
Same figures as the A310 repair guide: liner protrusion 0.16 to 0.23 mm, base gaskets blue 0.087 · white 0.102 · red 0.122 · yellow 0.147, 72 mm gudgeon pin, big-end nuts at 4.5 m.daN, main bearings pre-torqued to 3 m.daN then 75°, piston no. 1 at 15 mm before TDC to fit the heads.
604
On the Peugeot 604 Ti and STI, the ZMJ is the 144 bhp 2,664 cc with K-Jetronic — the mechanical injection also found on the Renault 30 TX, the Renault 25 and the Volvo 260 then 760.
Known variants

Two displacements under one code

The 604's 2.7 and the DeLorean's 2.85 — the full code table is on the Engines page.

ZMJ 130 to 144 bhp Every known code →
ZMJ144 bhp
K-Jetronic injection12-valve
Peugeot 604 Ti · 604 STI — 144 bhp, 2,664 cc; and the 1982 Heuliez 604 Limousine.
ZMJ-159130 bhp
K-Jetronic injectionLambda control12-valve
DMC DeLorean DMC-12 — 130 bhp SAE net, 2,849 cc, rear-overhang engine.
On the road

The cars of the ZMJ

Peugeot 604 Ti · STI →

The injected 604s: 144 bhp. And Philippe Bouvard's Heuliez 604 Limousine, a ZMJ-powered rolling office — the story is in Pop culture.

DeLorean DMC-12 →

The time machine: ZMJ-159, 130 bhp, eight workshop documents in the Library — training manual, injection, ignition, adjustments.

In the workshop

What the documents say about the ZMJ

Answers taken from our FAQ, each one read in the Library. The full FAQ holds several hundred more, engine code by engine code.

The ZMJ, in the documents The full FAQ →
DeLorean
Which PRV V6 exactly does the DeLorean DMC-12 use?
A 2,849 cc rear-mounted engine — 91 mm bore, 73 mm stroke, 8.8 compression ratio — giving 130 bhp SAE net at 5,500 rpm and 220 Nm at 2,750, with Bosch K-Jetronic injection and a Lambda system for the American market. Its figures come from the DeLorean training manual, in the Library. It is an uneven-fire PRV, that is to say the original three-crankpin crankshaft: the split-crankpin, even-fire version came later. Same capacity as the Volvo B28. See the specifications →
À chaud
Why does a DeLorean struggle to restart when hot?
The engine is not to blame: it is a matter of fuel pressure. K-Jetronic injection must stay pressurised once the ignition is off — 3.3 bar of rest pressure at switch-off, and still at least 1.7 bar after 10 minutes. If it collapses, the heat of the stopped engine boils the fuel in the injector lines lying in the vee, and there is nothing but vapour behind injectors that only open at 3.5 bar: you crank until the vapour is purged. The usual culprits: the fuel accumulator, the pump's check valve, a seal in the fuel distributor, a mixture set too lean — sealed parts that are replaced, not repaired. The 144 bhp Renault 25 V6 injection (Z7V) asks for the same values. DeLorean workshop manual, folio D:02:01. The Journal article →
Réglages
What ignition timing and idle speed on a DeLorean DMC-12?
13° ± 2 BTDC, at idle, engine at normal temperature — idle of 775 rpm ± 50 (automatic in park). Adjust by loosening the distributor hold-down nut and turning the body. One check comes first and is easily forgotten: with the vacuum hose disconnected at the distributor there must be NO vacuum at idle. If there is, the fault is in the idle speed control — limit switch adjustment, distributor vacuum cut-off solenoid, TVS thermal switch — and not in the ignition. DeLorean training manual, adjustments chapter, A1.
Guide Alpine
Is the DeLorean workshop manual a translation of the Alpine guide?
It derives from it very directly, and a cross-reading leaves little doubt. Same dimensions: liner protrusion 0.16 to 0.23 mm “as close to 0.23 as possible”, base seals blue 0.087 · white 0.102 · red 0.122 · yellow 0.147, 72 mm piston pin, rings 1.5 / 2 / 4 mm, thrust washers 2.30 · 2.40 · 2.45 · 2.50, rod nuts at 4.5 m.daN, mains pre-torqued to 3 m.daN then 75°. Same gestures: pin shrunk at 250 °C with a piece of solder as the gauge, rocker shaft turned round but never reversed, 5.35 and 8.2 mm spacers, piston no. 1 15 mm before TDC to fit the heads, 150° of crankshaft between left and right timing, right down to the wording on the tensioners: “ne pas aider son action” — “do not assist the tensioner”. Even the same worked example for shim selection (0.10 and 0.08 mm, hence a red tag). The DeLorean did not merely receive Renault's engine: it received its workshop documentation. Alpine A310 2700 VA repair guide, engine section, folios B-9, B-19, B-35, B-46, B-49 and B-65; DeLorean workshop manual, engine section.

In the Library

The DeLorean documents, searchable page by page — no Peugeot 604 document is in the Library yet: DeLorean — specifications and capacities · DeLorean — the engine explained (training manual) · DeLorean — workshop manual, engine section · DeLorean — K-Jetronic injection explained · DeLorean — ignition · DeLorean — adjustments, tests and diagnosis

The rest of the family

Architecture, generations and every known engine code of the PRV V6 — on the main Engines page.

ZM — the 2.7 carburettor →ZNJ — the 604 GTI's 2.8 → All PRV engines →