December 6, 2022

It’s a YB’d Sierra that received’t attempt to kill you on each journey; the Ford Sierra Sapphire Cosworth 4×4 has shed its taxi picture to develop into the most cost effective, most usable – and oh-so-tuneable – Cossie of all. Right here’s learn how to purchase a great one.

Information from Quick Ford. Phrases: Dan Williamson. Photographs: Jamie King

Ford Sierra Sapphire Cosworth 4×4 historical past

  • January 1988 – Sierra Sapphire RS Cosworth launched with rear-wheel drive, 204bhp YBB engine (205 block), T5 gearbox, 7x15in lattice alloy wheels, four-door bodywork, entrance and rear spoilers, aspect skirts and Recaro seats.
  • January 1990 – Sierra Sapphire RS Cosworth 4×4 launched, primarily based carefully on the earlier Sapphire Cosworth however with stronger cylinder block (200), revised head, larger intercooler and 220bhp. Now with Sierra XR4x4-type viscous-coupled four-wheel-drive system and MT75 gearbox, floating entrance brake callipers, ventilated rear discs, clear entrance indicators, smoked back lights, vented bonnet and 4×4 badges. Recaro seats commonplace in Raven/Halley fabric or elective Raven leather-based.
  • August 1991 – Facelifted 4×4 with shark-tooth alloy wheels, modernised dashboard, House fabric upholstery, electrical sunroof and catalytic converter.
  • March 1992 – Gentle-feel four-spoke plastic steering wheel replaces leather-based.
  • December 1992 – Sapphire Cosworth manufacturing ends. Closing automobiles obtain single-colour rear spoiler with out painted black lip. Round 12,250 produced in whole, all at Genk, Belgium.

Engine & Transmission

For those who’re studying this, the YB wants no introduction: it’s a world-class motor, it’s able to large energy, and it prices a bomb to place proper when it breaks. And it does break.

First, make certain a Sapphire 4×4 has the correct (stronger) YBJ/YBG engine – the block ought to have ‘200’ solid into the aspect in massive digits, and positively not ‘205’. Till August 1991 it had a purple cam cowl; afterwards a inexperienced cam cowl and catalytic converters.

Hear for nasty noises from chilly. Knocking, growling or tapping from the underside finish suggests a worn crank or bearings, knackered pistons or scored bores. Very dangerous information.

Smoking could also be equally critical. Plumes of black soot beneath throttle imply it’s operating wealthy, blue smoke factors to worn pistons/rings or drained turbo (wiggle the compressor wheel to test for play), and white clouds recommend head gasket failure or broken cylinder head – look out for water within the oil or exterior coolant leaking down the block.

Poor efficiency may have a sinister or easy trigger, however may have intensive diagnostics. Increase issues might end result from cut up or unfastened hoses, sensors and regulators. Misfires beneath load are sometimes as a consequence of spark plugs, leads or coil – however might be extra critical.

Dangerous wiring, poor connections and chafed cables can result in slow-starting, misfires and breakdowns. Cooling fan wiring tends to soften, so test the followers reduce in when the engine is heat. A brand new engine loom isn’t low cost however might be price each penny.

Examine the gas pump, filter and cradle (beneath the boot ground). In the event that they’re grotty and corroded, account for getting them changed. A pump that’s not getting 13 volts may trigger underfuelling extreme sufficient to kill the engine.

See also  ECU Remapping Guide | Everything You Need To Know

Except you’re looking for a museum piece, don’t be dissuaded by a modified Sapphire. The 4×4 wants not less than Stage 1 upgrades (chip, exhaust and -31 actuator) to really feel energetic. On the flip aspect a big-power Cossie might be a ticking time bomb, so ask to see receipts from a tuner – ideally a Cosworth specialist.

The Ford Sierra Sapphire Cosworth 4×4 structure is its energy however it’s additionally its weak point. The four-wheel-drive Sapphire provides nice grip however the transmission system could be fragile – particularly when requested to deal with 350bhp-plus of modified YB. A radical inspection is significant.

Make sure the gearchange is agency and exact. If there’s crunching or issue partaking gears – particularly on the down-change – worn synchromesh rings are possible, which means the MT75 wants a rebuild.

Nasty noises don’t bode nicely. A whining gearbox is on its final legs, and rattling at idle (sounds just like clutch bearing vibration) suggests the layshaft bearings are drained. Clonking or snatching driveshafts level to centre differential failure; vibrations might be from damaged propshaft joints or engine/gearbox mounts; loud clicking might be a knackered CV joint.

Clutch slip is simple to identify: ground the throttle at 3000rpm in fifth gear and make sure the automobile hastens because the revs enhance. A stiff pedal might be only a sticky cable.

Watch out for a 4×4 operating solely in rear-wheel drive – effective if completed correctly utilizing a T5 gearbox, however not if it’s as a consequence of a damaged centre diff.


A inventory Ford Sierra Sapphire Cosworth 4×4 feels stodgy and lifeless in contrast with a rear-wheel-drive Cossie. Think about three many years’ put on, and it received’t be a lot enjoyable.

Chief culprits for poor dealing with are drained suspension bushes: worn monitor management arm bushes trigger wandering from the entrance finish; trailing arm bushes end in sloppiness on the again. Powerflex polyurethane replacements are the easy and everlasting answer.

Vagueness at pace may additionally come from the steering. Knackered steering column bushes trigger an absence of really feel, and the Sapphire is susceptible to looseness on the steering rack, so jack up the automobile and really feel for play. Test for oil leaks from cut up gaiters, and ensure the PAS pump isn’t noisy.

Bushes may cause clonking noises, however test for damaged coil springs or drained dampers. It’s regular for Sapphires to be on aftermarket suspension, which typically improves dealing with, however coilovers are too stiff for a street automobile, and a drop better than 25mm dangers damaging the CV joints.

Sapphire 4x4s lacked the four-pot callipers of their predecessors – as an alternative fitted with Scorpio-type floating callipers – however not less than the rear discs have been ventilated. The pedal needs to be agency and communicative, and with respectable fast-road pads the stopping energy is appropriate. However in comparison with a contemporary machine, a Cosworth with duff brakes will really feel awful and downright harmful.

Juddering felt by the brake pedal and steering wheel is typical of contaminated discs and/or pads, though it’s price checking damaged suspension elements aren’t at fault. Pulling to 1 aspect beneath braking suggests a sticking entrance calliper; seized rears are notably widespread, particularly on the handbrake mechanism; jack up the automobile and test with it within the on or off place.


Cosworths used an honest Teves ABS setup, which generally causes issues from soiled/defective wheel sensors or damaged wiring. A failed ABS pump, blown fuses and fluid stage sensors may be responsible.

Ford Sierra Sapphire Cosworth 4x4


A Cossie with a tatty cabin tells you it’s led a tough life. It additionally says you’ll be spending money to get it again as much as scratch – so it pays to discover a Sapphire with a mint inside.

Test is the driving force’s seat, which can present put on on put on on the bolsters, collapsed foam, a damaged base or floppy recliner mechanism. A typical trick is to interchange it with a greater seat from the passenger aspect. Leather-based trim is extra widespread than fabric, however don’t pay a premium for both. Early Sapphire 4x4s had the identical darkish gray upholstery as late RWDs; from August 1991 it was swapped for so-called Rainbow fabric, which is uncommon if not precisely fascinating.

Vehicles of this age additionally had a curvier dashboard. Fortunately, a Sapphire sprint doesn’t crack like that of a three-door Cosworth, however test it isn’t broken or distorted. Rattling and creaking is all a part of the old-school-Ford attraction. Leather-based on the gearknob and steering wheel could also be worn; late automobiles had a horrible four-spoke plastic wheel.

Door playing cards are likely to have vinyl lifting from the backing the place it meets the glass; good replacements are arduous to seek out. It’s regular to see a headlining soiled or drooping, particularly within the rear passenger compartment, or stained across the sunroof if it’s been leaking. Reconditioned headlinings are available.

Speaking of sunroofs, test it for rot. A post-August 1991 Sapphire ought to have an electrical model, so guarantee it really works. Central locking and electrical window motors even have a behavior of seizing, however they’re the identical as unusual Sierra elements, so can nonetheless be sourced for smart cash.

Ford Sierra Sapphire Cosworth 4x4

Ford Sierra Sapphire Cosworth 4×4 physique

Corrosion has killed 1000’s of Sapphire Cosworths – so examine your potential buy notably rigorously.

Start beneath the bonnet (which on a 4×4 ought to characteristic factory-fitted vent cutouts). Internal wings are inclined to rot, particularly beneath the header tank and across the suspension turrets, which in extreme instances can collapse. Bulkhead rust can be critical, so look across the battery tray and beneath the fuse field.

Examine the entrance crossmember and chassis rails; a real 4×4 ought to have Ford-produced half-moon recesses for the driveshafts, so stroll away from something that appears home-made.

Look at the whole underside – particularly the rear chassis field sections beside the spring seats, together with the floorpans and sills. Sunroof leaks can play havoc.

The doorways, entrance wings, interior and outer wheelarches, boot ground and boot lid could also be rusty, however most physique panels are shared with common Sapphires, so that they’re not too expensive. Vented 4×4 bonnets have gotten costly, as are the entrance bumper and aspect skirts, that are susceptible to sagging. Test the entrance grille doesn’t have snapped lugs, and make sure the again bumper isn’t wonky as a result of undamaged replacements are uncommon.


Don’t overlook Cosworths have been well-known for being crashed, so be careful for accident injury, resembling creases within the floorpan (don’t fear an excessive amount of about flattened jacking factors), interior wings and boot ground, dangerous panel gaps and poor paintwork.

Some rarer colors – resembling Radiant Crimson – carry a small premium, however except you’re set on a specific color, purchase on bodywork situation alone.

Ford Sierra Sapphire Cosworth 4x4


Cossies are infamous for being nicked, crashed and faked, so it’s essential to put money into a full historical past test – and never an affordable cellphone app.

Examine the chassis quantity: you’ll discover it on the VIN plate (riveted to the bonnet slam panel) and stamped into the ground beneath a carpet flap beside the driving force’s seat. It ought to match the digits on the V5 log e-book, studying WFOFXXGBBF adopted by two letters (for the construct date) and 5 numbers, which mirror the engine quantity. Bear in mind, a 4×4 ought to have a cylinder block with massive ‘200’ casting numbers on the crankcase.

Different digits on the VIN plate ought to learn N5 for engine code, B (right-hand drive) for drive, 8 for trans, U for axle, and BFGC4 within the kind field.

Make sure the automobile you’re inspecting matches the 12 months, color and spec it’s claiming to be. All 4x4s had a vented bonnet, clear entrance indicators and tinted rear mild lenses; a right-hand-drive road-car shell ought to have a factory-pressed cutout behind the brake servo, straight towing eye, glass sunroof, and driveshaft cutouts within the chassis rails.

Fakes and replicas are surprisingly widespread, price significantly lower than authentic Cosworths.

Run away from any Cossie with a doubtful previous. If it’s too low cost to be true, don’t be stunned to see a ground-off chassis quantity and a mishmash of stolen elements.

Ford Sierra Sapphire Cosworth 4x4

Ford Sierra Sapphire Cosworth 4×4 tech spec


1993cc four-cylinder, 16V, DOHC Ford Cosworth YBG/YBJ with forged iron 200 block and alloy cylinder head, 8.0:1 compression ratio, toothed belt drive, Weber-Marelli multi-point gas injection and digital administration system, Garrett T03 turbocharger with intercooler


4-wheel drive with MT75 five-speed guide gearbox, viscous coupling entrance and limited-slip viscous coupling rear differentials, 34/66 per cent entrance/rear cut up, 242mm clutch. Closing drive ratio: 3.62:1


Entrance: MacPherson struts, gas-filled dampers, coil springs, decrease monitor management arms, 28mm anti-roll bar; rear: unbiased, semi-trailing arms, coil springs, gas-filled dampers, 18mm anti-roll bar


Entrance: 278mm ventilated discs; rear: 273mm ventilated discs; Teves ABS

Wheels & tyres:

7Jx15in RS alloys and Bridgestone ER90 205/50 ZR15 tyres


Sierra Sapphire four-door saloon with colour-coded bodykit comprising deep entrance bumper with fog lamps, aspect skirts and rear spoiler, bonnet vents, colour-coded mirrors, electrical entrance and rear home windows, tilting/sliding glass sunroof (electrically operated from August 1991). Colors: Diamond White, Magenta, Moonstone Blue, Flint Gray, Ebony Black (metallic), Black (gloss), Moondust Silver, Smokestone Blue, Nouveau Crimson, Radiant Crimson, Pacifica Blue and Mallard Inexperienced


Ghia-level with Recaro entrance seats in Halley (till August 1991) or House (from August 1991) cloth trim (Raven leather-based elective), three-spoke leather-covered steering wheel (four-spoke plastic from March 1992), adjustable steering column, 170mph speedometer, leather-covered gearknob, elective air con