Arama
← DTC Listesine Dön
OBD-II DİZEL ATÖLYE PROTOKOLÜ8-10 min read
P0304Ateşleme ve DengeYüksek Önem💡 Motor Arıza Lambası Yanıyor⚠️ Koruma Modu Aktif

P0304: 4. Silindirde Yanma Başarısızlığı / Tekleme Tespit Edildi

FuelPartsDB Teknik Mühendislik EkibiYayınlanma: Son Güncelleme: Uzmanlık: Common Rail Sistemleri

Arıza Teşhis Kodu (DTC) P0304, Motor Kontrol Modülünün (ECM/PCM) özellikle 4. silindire özgü tam bir yanma arızası veya tekrarlayan bir yanma başarısızlığı (tekleme) tespit ettiğini gösterir. Bujili ateşleme sistemi bulunmayan ortak hatlı (common rail) dizel bir motorda yanma arızası tespiti, yalnızca yüksek çözünürlüklü Krank Mili Konum (CKP) sensörünün krank milinin açısal hızındaki mikrosaniye altı dalgalanmaları izlemesiyle hesaplanır. 4. silindirin iş stroku (Üst Ölü Noktadan Sonra / ATDC 30° - 90°) kalibre edilmiş eşik değerlerini aşan (tipik olarak izlenen yanma çevrimlerinin >%2,0'si) bir açısal ivmelenme piki üretmek yerine dönme hızında bir yavaşlama düşüşüne neden olduğunda P0304 kodu kaydedilir.

🚗 SÜRÜCÜ REHBERİ VE ONARIM PROTOKOLÜ

🚗 Sürüş Güvenliği, Tahmini Onarım Maliyeti ve Doğrulama

🔴 Kritik: Sürüşü Durdurun / Çekici Gerekli
  1. 01

    🚦 Sürüş Güvenliği ve Mekanik Risk

    Acil mekanik değerlendirme ve çekici gereksinimi

    4. Silindir Yanma Arızası - Arka Silindirde Yüksek Termal Risk

    4. silindir (sıralı 4 silindirli motorların çoğunda göğüs sacına en yakın silindir) tekleme yapmaktadır. Arka silindirler daha zayıf hava akışı nedeniyle daha sıcak çalıştığından, fakir veya zengin karışımlı yanma arızasıyla uzun süre araç kullanmak bölgesel termal gerilime ve silindir kapak contası hasarına yol açabilir.

    SÜRÜŞE DEVAM EDİLMESİ DURUMUNDA MOTOR RİSKLERİ:Silindir kapağında bölgesel aşırı ısınma kaynaklı termal hasar, egzoz strokunda yanmamış yakıtın alev almasıyla egzoz supaplarının yanması ve ani DPF (Dizel Partikül Filtresi) kurum aşırı yüklenmesi.
    Araçta Gözlemlenen Belirtiler:
    • Severe engine vibration and rhythmic shudder noticeable through steering wheel and floorpan
    • Deep engine chugging sound and distinct loss of acceleration under any uphill load
    • Exhaust tailpipe emits greyish smoke with pungent raw unburnt diesel odor
    • Cruise control disabled and transmission shifting erratically
  2. 02

    💰 Servis Onarım Bütçesi

    Beklenen parça değişimi ve servis işçilik maliyet kademeleri
    Küçük Bakım / Filtre Temizliği1.200 TL - 3.500 TL: Enjektör soket pini sıkılaştırma, yakıt filtresi değişimi ve kızdırma bujisi iç direnç kontrolü.

    Sensör temizliği, yakıt filtresi değişimi, sigorta kontrolü veya kablo soketi temizliği.

    Valf / Sensör Değişimi7.500 TL - 16.500 TL: Yeni bakır pul ve sabitleme cıvatası ile kaliteli revizyonlu (reman) enjektör değişimi.

    Tek bileşen değişimi (basınç regülatörü, dozaj valfi veya revizyonlu enjektör).

    Ağır Onarım / Pompa ve Enjektörler35.000 TL - 85.000 TL+: Yeni orijinal fabrika çıkışı enjektör, yüksek basınç borusu ve kurum tıkalıysa emme manifoldu ceviz kumlama (walnut blasting) temizliği.

    Yüksek basınç pompası revizyonu, yeni OEM enjektör takımı veya DPF değişimi.

    Servis referans fiyatları. Arızaların %70'inden fazlası komple parçalar değiştirilmeden Seviye 1 veya 2 dahilinde çözülür.

  4. 03

    🧰 Hızlı Görsel ve Fiziksel Kontroller

    Servisi aramadan önce aletsiz 5 dakikalık hızlı kontrol
    1Göğüs sacı yakınındaki 4. silindir kablo tesisatını kontrol edin: Motor kablo tesisatının sıcak egzoz ve EGR borularına yakın geçtiği yerlerde sürtünme veya erime olup olmadığını inceleyin.
    2Egzoz kokusunu kontrol edin: Yoğun çiğ dizel buharı kokusu, yakıtın silindire püskürtüldüğünü ancak düzgün şekilde tutuşmadığını gösterir.
    3Motor yağ dolum kapağını inceleyin: Kapaktaki kremsi mayonez kıvamındaki emülsiyon, enjektör probleminden ziyade silindir kapak contasından kaynaklanan soğutma sıvısı ve yağ karışımına işaret eder.
  5. 04

    🛡️ Yanıltıcı Arıza Teşhisine Karşı Koruma

    Gereksiz parça değişimini önlemek için tamirciye sorulacak sorular
    "Ustanıza şunu söyleyin: 'Mekanik aksamı suçlamadan önce lütfen 4. silindir enjektör selenoidi üzerinden elektriksel direnç ölçümü (ohm) yapın (fabrika toleransı 0.2 - 0.5 ohm arasıdır).'"
    "Ustanıza şunu söyleyin: 'Yeni taktığınız enjektörün 6, 7 veya 8 karakterli IMA/IQA kalibrasyon kodunu motor kontrol ünitesine (ECU) tanıttığınızdan emin olun.'"

    Teknik Not: Yüksek maliyetli parça değişimini onaylamadan önce ustanıza bu soruları yöneltin:

🔧 UZMAN TEKNİSYEN TAVSİYESİ VE ONARIM PROTOKOLÜRAPID ASSESSMENT

30 Saniyelik Hızlı Atölye Triyajı

Temel Belirtiler
  • Violent engine shaking, severe vibration, and rhythmic thumping at idle (running distinctly on 3 cylinders)
  • Flashing or steady Check Engine Light (MIL) on dashboard, accompanied by flashing glow plug light and ESP/traction warning
  • Massive loss of engine power, sluggish throttle response, and inability to accelerate up highway gradients
En Olası Nedenler
  • Completely failed Cylinder 4 fuel injector (blown solenoid coil, seized command piston, or cracked nozzle needle)
  • Low mechanical cylinder compression on Cylinder 4 caused by a burnt exhaust valve, broken rocker arm, or holed piston (runs hottest near firewall)
  • Burned-out or heavily carbon-crusted Cylinder 4 glow plug preventing compression ignition during cold ambient starts
İlk Gerekli İşlem

Connect scan tool live telemetry: compare Target Fuel Rail Pressure vs Actual Rail Pressure and log metering valve command PWM duty cycle during idle and road load.

🛠️ Geri Dönüş (Back-Leak) Denge Analizörü

Expensive Diagnostic Pitfall & Technical Reality

❌ Yaygın servis yanılgısı:

P0304 means Cylinder 4 has suffered piston ring failure or burned exhaust valves, requiring cylinder head removal ($2,000 - $3,800).

🔍 Teknik ve hidrolik gerçeklik:

Cylinder 4 sits closest to the firewall where heat dissipation is poorest, making its injector harness wiring and sealing components prone to premature thermal aging. In over 80% of verified cases, mechanical compression is normal. The misfire is almost always caused by an injector with a clogged nozzle spray hole from carbon coking, a degraded harness connector whose spring leaves have widened under heat, or high internal valve backleak.

💡 Teknik doğrulama protokolü:

Unnecessary engine rebuild or full injector set replacement ($2,400+) vs ultrasonic cleaning of the nozzle ($0) or repairing the $15 harness pigtail connector, saving over $2,200.

Severe Piston Crown Torching & DPF Thermal Destruction Alert

CRITICAL WORKSHOP WARNING: Never drive a diesel vehicle with an actively flashing Check Engine Light or code P0304! If the misfire is caused by a leaking, unseated, or cracked injector nozzle needle, un-atomized liquid diesel fuel sprays continuously into Cylinder 4. Under highway combustion temperatures, this creates an intense blowtorch effect that burns a hole straight through the center of the aluminum piston crown, blowing combustion pressure into the crankcase and causing catastrophic diesel engine runaway!

MANDATORY PROTOCOL: Furthermore, unburned diesel fuel exiting Cylinder 4 enters the exhaust stream and collects inside the Diesel Particulate Filter (DPF). When the DPF attempts thermal regeneration, the raw diesel ignites like a furnace, exceeding 1200°C and melting the ceramic core. Stop driving immediately and perform an injector backleak and compression test.

PLATFORM ARCHITECTURE

En Çok Etkilenen Motorlar ve Enjeksiyon Sistemleri

Bu arıza kodu öncelikle aşağıdaki common rail dizel platformlarını etkiler. Fabrika arıza modelleri ve parça numaraları için motor ailenizi inceleyin:

Ford / PSA 1.6 TDCi / HDi (DV6ATED4 / DV6TED4)

Bosch CRI2 Solenoid Common Rail

Tipik Belirti: Distinct chuffing exhaust sound from rear of engine, tar crust encrusting injector 4, and P0304 stored.

Bilinen Fabrika Arıza Modeli: Crushed copper sealing washer blow-by due to injector hold-down clamp stud loosening under thermal cycling.

Temel Alt Parça:0445110239 (Injector) / PSA 198299 / 198185 (Seal Kit)
Ford / PSA 1.6 TDCi / HDi (DV6ATED4 / DV6TED4) Motor Teknik Merkezini İncele →

Mercedes-Benz 2.1 CDI OM651 (Sprinter, C220 CDI, E220 CDI)

Delphi CRD2 / CRD3 Common Rail

Tipik Belirti: Severe cab vibration at idle, engine enters Limp-Home Mode, and Cylinder 4 smooth running value pegged in Xentry.

Bilinen Fabrika Arıza Modeli: Delphi injector control valve internal micro-grooving dumping high return volume back to tank on rear cylinder.

Temel Alt Parça:A6510704987 / Delphi 28342997 / 28348371
Mercedes-Benz 2.1 CDI OM651 (Sprinter, C220 CDI, E220 CDI) Motor Teknik Merkezini İncele →

Volkswagen / Audi 2.0 TDI EA189 / EA288 (Golf, Passat, Tiguan, A3, A4)

Bosch CRI2.2 Solenoid / CRI3 Piezo

Tipik Belirti: Flashing glow plug spiral indicator on instrument cluster accompanied by harsh cold-idle clatter on Cylinder 4.

Bilinen Fabrika Arıza Modeli: Cylinder 4 injector control valve seat erosion or piezo stack moisture penetration causing delivery collapse.

Temel Alt Parça:0445110369 / 03L130277B (Bosch CRI2.2 Injector)
Volkswagen / Audi 2.0 TDI EA189 / EA288 (Golf, Passat, Tiguan, A3, A4) Motor Teknik Merkezini İncele →

BMW 2.0d N47 / B47 (120d, 320d, 520d, X1, X3)

Bosch CRI3 Piezo / Solenoid Common Rail

Tipik Belirti: Rough idle when cold, drivetrain malfunction message in iDrive, and intermittent P0304 code stored.

Bilinen Fabrika Arıza Modeli: High thermal stress on rear cylinder causing injector 4 piezo crystal micro-cracking and electrical leakage to ground.

Temel Alt Parça:0445115077 / 0445116001 / BMW 13537796042
BMW 2.0d N47 / B47 (120d, 320d, 520d, X1, X3) Motor Teknik Merkezini İncele →
WORKSHOP MASTER TEARDOWN GUIDE

Cylinder Balance & Injector Deviation Guide

Common rail diesel cylinder balance & smooth running diagnostic guide. Balance rates, mg/stroke deviation, P0263 misfire, compression vs injector test.

Read Full Master Guide →
THEORY OF OPERATION

Kontrol Devresi ve Aktüatör Çalışma Mantığı

1. Dynamic In-Demand Fuel Metering

Diesel compression ignition requires three mandatory physical conditions: high cylinder compression (>22 bar producing air temperatures above 500°C), precise atomization of high-pressure diesel fuel (>250 bar cranking, >1400 bar running), and exact injection timing. The ECM tracks the rotational speed of the flywheel tone ring (60-2 or 36-2). When Cylinder 4 fires correctly, crankshaft rotational speed accelerates sharply. If combustion fails completely (zero heat release), the drag of compressing air causes the crankshaft to slow down rapidly during Cylinder 4's segment, triggering the misfire monitor.

2. Closed-Loop PID Deviation Monitoring

The ECM evaluates misfire data across two independent severity windows: 1. Catalyst / DPF Damaging Window (200 engine revolutions): If the misfire rate is severe enough to allow raw fuel into the exhaust (causing DPF melting), the Check Engine Light flashes violently. 2. Emissions Compliance Window (1,000 engine revolutions): If misfire percentage exceeds 2.0% to 3.0%, a continuous DTC P0304 is logged. The ECM attempts initial compensation by adding fuel via Smooth Running Control (SRC); if the cylinder fails to respond, the ECM cuts fuel to Cylinder 4 to prevent catalytic converter destruction.

3. Diagnostic Trap: Normally Open (NO) vs Normally Closed (NC) Valves

Misfire (P0304) vs Balance Contribution (P0272) Diagnostic Rule: P0272 indicates PARTIAL combustion (the cylinder is running but producing less torque due to coked nozzle holes or minor leakage). P0304 indicates a COMPLETE DEAD MISS: Cylinder 4 has suffered complete combustion failure. In diesel workshops, a dead miss on Cylinder 4 is frequently caused by its location at the rear of the cylinder head against the firewall: it runs with the highest thermal heat soak, leading to accelerated injector nozzle varnish baking, valve guide wear, and head gasket fire ring fatigue.

ENGINEERING SPECIFICATIONS

Elektriksel ve Hidrolik Fiziksel Standartlar

Solenoid Coil DC ResistanceCommon Rail Solenoid Injector: 0.20 - 0.45 Ω @ 20°C; Piezo Injector: 180 kΩ - 220 kΩ (Capacitance: 2.5 - 3.5 µF)Measured @ 20°C across terminals 1 & 2
Insulation Resistance> 10 MΩ measured between injector electrical terminals and cylinder head chassis groundBetween terminals and pump body (ground)
Operating Supply VoltageECM Injector Driver Voltage: 80 V - 90 V DC peak boost (Solenoid) or 140 V - 200 V DC high-voltage pulse (Piezo)High-side feed from ECM / main relay
PWM Frequency StandardMulti-pulse current waveform; Peak pull-in current: 20 A - 30 A; Hold current: 10 A - 12 ASquare-wave PWM modulation
Idle Duty Cycle (Warm Engine)Cylinder 4 Balance Fuel Trim (SRC): Pegged at maximum enrichment limit (+4.5 to +6.0 mg/stroke)Nominal baseline at 250–350 bar
Full-Load Duty Cycle (WOT)Dynamic Backleak Flow Limit: < 25 mL/min per injector @ warm idle; < 5 mL total during 15s starter crankingMaximum high-speed fuel delivery demand
Low-Pressure Feed SupplyMechanical Cylinder Compression: 22.0 to 32.0 bar (320-465 psi); Minimum cranking threshold > 18.0 barMeasured at pump fuel inlet
Internal Cascade BackpressureGlow Plug Resistance (Cold Start Diagnostic): 0.4 to 1.2 Ω @ 20°C (ceramic/metal low-voltage glow plug)Controlled by overflow cascade valve
PROCEDURAL PROTOCOL

Adım Adım Atölye Teşhis Protokolü

STEP 1

Injector Cross-Swap Physical Verification (Hardware vs Mechanics)

Remove the Cylinder 4 fuel injector and swap it with Cylinder 1 (using brand-new annealed copper crush washers). Reprogram the respective IMA/QR calibration codes into the ECM via scan tool. Clear trouble codes and start the engine. If the misfire code moves from P0304 to P0301 (Cylinder 1), the injector has an internal mechanical/hydraulic failure: replace it. If the misfire remains stubbornly on Cylinder 4 (P0304), the problem is 100% mechanical (compression/valvetrain) or wiring.

STEP 2

Electronic Relative Compression & Mechanical Gauge Test

Execute an electronic 'Relative Compression Test' via diagnostic scan tool, which monitors starter current draw and crankshaft angular speed across each cylinder's compression stroke. If Cylinder 4 shows <85% relative compression, remove the Cylinder 4 glow plug and thread in a physical diesel mechanical compression gauge. Crank engine: compression must exceed 22 bar (320 psi) with <3 bar variance to companion cylinders. A reading below 18 bar confirms blown piston rings, burnt valves, or a blown head gasket.

STEP 3

Individual Injector Backleak (Return Flow) Measurement

Disconnect the low-pressure fuel return lines from all injectors. Attach graduated transparent test tubes to the return nipples. Crank the engine for 15 seconds (or run at warm idle for 2 minutes). A healthy injector returns less than 20-25 mL at idle. If Cylinder 4 returns excessive fuel (>40 mL) or fills the bottle instantly during cranking, its internal control valve has collapsed, dumping rail pressure and preventing the needle from lifting.

STEP 4

Injector Solenoid Coil Resistance & 250V Megohmmeter Test

Disconnect the Cylinder 4 injector harness. Using a precision digital multimeter on the 200 Ω scale, measure coil resistance: solenoid injectors must measure 0.20 Ω to 0.45 Ω @ 20°C; piezo injectors must measure 180 kΩ to 220 kΩ. Next, test insulation resistance to the metal body with an automotive insulation tester set to 250V/500V test voltage (must exceed >10 MΩ). A low reading confirms high-voltage dielectric breakdown arcing into the cylinder head.

STEP 5

Glow Plug Resistance & Power Feed Audit (Cold Start Misfires)

If the P0304 misfire occurs exclusively during the first 3 to 5 minutes following a cold start, disconnect the Cylinder 4 glow plug lead. Measure resistance between the glow plug center terminal and engine cylinder block ground. A healthy glow plug measures 0.4 Ω to 1.2 Ω. An open circuit (infinite resistance / OL) confirms a burned-out glow plug that leaves Cylinder 4 too cold to ignite diesel.

STEP 6

Cylinder 4 Valvetrain & Camshaft Lobe Inspection

Remove the engine valve/camshaft cover. Visually inspect the intake and exhaust camshaft lobes and roller rocker arms for Cylinder 4. Look for worn, flattened camshaft lobes (very common on high-mileage VAG TDI and Ford engines) or collapsed hydraulic lash adjusters. A flattened intake cam lobe prevents the intake valves from opening fully, starving the cylinder of oxygen.

COMPONENT-LEVEL REPAIR

Donanım Onarımı ve Yedek Parça Listesi (BOM)

Cylinder 4 Fuel Injection & Combustion Chamber Sealing Interface

Bosch CRI2 / CRI3 Solenoid Injector Assembly - Cylinder 4

0 445 110 369 / 0 445 116 059

High-speed electro-hydraulic fuel injector with calibrated pilot/main injection metering

OEM: Protocol: Replace or rebuild if dynamic backleak exceeds 35 mL/min or spray pattern is distorted
Heat-Treated Annealed Copper Injector Sealing Washer (1.5mm - 2.0mm)

F 00V C17 503 / OEM Copper Crush Washer

Gas-tight sealing ring between injector nozzle shoulder and cylinder head bore seat (prevents combustion blowby)

OEM: Protocol: Mandatory one-time use; never reuse a crushed copper washer
High-Temperature 2-Pin Injector Connector Repair Kit with Silicone Boots

1 928 498 056 / Tyco Junior Timer 2-Way

Provides positive terminal spring tension to withstand 150V injection pulse vibrations

OEM: Protocol: Replace if pin drag test feels loose (< 1.5N retention force) or locking latch is broken
Workshop Technical & Economic Benchmark: Injector clamp stretch bolt: 7 Nm + 90° angle turn; Hand seat reamer cutter with pilot guide; Beru ceramic anti-seize paste.
LIVE WORKSHOP TOOL

Canlı Common Rail Tolerans Hesaplayıcı

Injector Dynamic Back-Leak Balance Analyzer

Input return fuel volume collected per cylinder in 2 minutes of idle. Pinpoint if Cylinder 4's return flow exceeds 35 mL/min, indicating internal hydraulic valve wear.

📐 Factory Engineering Tolerance: Max Allowable Return Deviation: < 3:1 Ratio Between Cylinders
Launch Dedicated Calculator with Factory Tolerances →
OEM REPLACEMENTS

İlgili Common Rail Parçaları

The following genuine OEM fuel pumps and common rail injectors are verified factory equipment for engines reporting fault protocol P0304. Cross-reference operating pressures and tightening torques before sub-assembly replacement:

Common Rail Injector

0445115077BOSCH

BOSCH 0445115077 Piezo Common Rail Injector for BMW 330d / 530d / X5 3.0d M57N2

View Technical Specs & Fitment →
Common Rail Injector

0445110239BOSCH

0445110239 Injector: PSA 1.6 HDi Ford 1.6 TDCi Specs

View Technical Specs & Fitment →
Common Rail Injector

0445110369BOSCH

0445110369 Injector: VW 2.0 TDI EA189 CFFB CFHC Specs

View Technical Specs & Fitment →
Common Rail Injector

095000-5880Denso

095000-5880 Denso Toyota 2KD-FTV Injector: 23670-30050 Data

View Technical Specs & Fitment →
Common Rail Injector

28337917Delphi

28337917 Delphi Bobcat D24 Injector: 7030364 Specs & Data

View Technical Specs & Fitment →
Common Rail Injector

095000-8340Denso

095000-8340 Denso Mitsubishi 4D56 HP Injector: 1465A367 Data

View Technical Specs & Fitment →
CALIBRATION RELEARN

Yüksek Basınç Pompası Adaptasyon Sıfırlama ve Test

Following replacement of the Cylinder 4 fuel injector, glow plug, or cylinder head servicing, execute the adaptation routine:

1. Enter the new 6-to-30 digit alphanumeric calibration code (IMA/QR code) stamped on the top of the new Cylinder 4 injector into the ECM via scan tool.

2. Clear all stored diagnostic trouble codes and confirm engine coolant temperature is above 75°C (167°F).

3. Access scan tool 'Engine Control Module' -> 'Special Functions' -> select 'Reset Cylinder Balance / Smooth Running Values'.

4. Start the engine and allow it to idle undisturbed in park/neutral for 5 minutes without touching any pedals, allowing the ECM to build initial torque offsets.

5. Accelerate vehicle smoothly in 4th gear to 80 km/h (2200 RPM), then release throttle completely to coast down in gear to 35 km/h (minimum 8s overrun).

6. Repeat this acceleration and coast-down sequence 5 times. Return to workshop and confirm Cylinder 4 misfire counter remains at absolute zero.

DIFFERENTIAL DIAGNOSIS

Diferansiyel Teşhis ve İlgili Hata Kodları

P0300

Random or Multiple Cylinder Misfire Detected

Multi-cylinder misfire code triggered when systemic issues (air in fuel, bad fuel, low rail pressure) cause misfiring across multiple cylinders.

P0272

Cylinder 4 Contribution/Balance Fault

Milder predecessor fault indicating Cylinder 4 is producing degraded torque; if contribution degrades further into complete flameout, P0304 triggers.

P0204

Injector Circuit/Open - Cylinder 4

Electrical circuit fault code on Cylinder 4; if an injector wiring open/short develops, P0204 will trigger alongside or override P0304.

FIELD REPAIR REPORTS

Atölye Saha Vaka İncelemeleri

CASE #1

2016 Mercedes-Benz Sprinter 316 CDI (OM651)(210,000 km)

Reported Complaint:Constant rhythmic engine chugging at idle with heavy lack of power; DTC P0304 stored.
Teardown Root Cause:Relative compression test showed even engine speed. Bench testing Cylinder 4 injector revealed 2 of the 7 micro-spray holes were completely plugged with carbon coke, causing severe spray pattern distortion and combustion failure.
Repair Solution:Fitted replacement nozzle assembly (DLLA150P1828) and new harness pigtail connector. Reinstalled injector with fresh copper washer; idle smoothed out immediately and P0304 was eliminated.
DIAGNOSTIC FAQ

Sıkça Sorulan Teknik Sorular

P0304 motor arıza kodu ne anlama gelir?

Arıza Teşhis Kodu (DTC) P0304, Motor Kontrol Modülünün (ECM/PCM) özellikle 4. silindire özgü tam bir yanma arızası veya tekrarlayan bir yanma başarısızlığı (tekleme) tespit ettiğini gösterir. Bujili ateşleme sistemi bulunmayan ortak hatlı (common rail) dizel bir motorda yanma arızası tespiti, yalnızca yüksek çözünürlüklü Krank Mili Konum (CKP) sensörünün krank milinin açısal hızındaki mikrosaniye altı dalgalanmaları izlemesiyle hesaplanır. 4. silindirin iş stroku (Üst Ölü Noktadan Sonra / ATDC 30° - 90°) kalibre edilmiş eşik değerlerini aşan (tipik olarak izlenen yanma çevrimlerinin >%2,0'si) bir açısal ivmelenme piki üretmek yerine dönme hızında bir yavaşlama düşüşüne neden olduğunda P0304 kodu kaydedilir.

P0304 kodunun en yaygın belirtileri nelerdir?

Violent engine shaking, severe vibration, and rhythmic thumping at idle (running distinctly on 3 cylinders), Flashing or steady Check Engine Light (MIL) on dashboard, accompanied by flashing glow plug light and ESP/traction warning, Massive loss of engine power, sluggish throttle response, and inability to accelerate up highway gradients, Dense clouds of white or blue-grey exhaust smoke on cold start (raw unburned atomized diesel fuel vapor), Overwhelming raw diesel exhaust odor noticeable around the vehicle and through cabin air vents, Scan tool live data shows Cylinder 4 misfire counter incrementing rapidly (>50 counts per 1000 revolutions).

Dizel motorda P0304 arızasına ne sebep olur?

Completely failed Cylinder 4 fuel injector (blown solenoid coil, seized command piston, or cracked nozzle needle); Low mechanical cylinder compression on Cylinder 4 caused by a burnt exhaust valve, broken rocker arm, or holed piston (runs hottest near firewall); Burned-out or heavily carbon-crusted Cylinder 4 glow plug preventing compression ignition during cold ambient starts; Broken, corroded, or shorted wiring harness wire between the ECM and the Cylinder 4 fuel injector connector; Internal low-side power MOSFET driver transistor failure for Cylinder 4 inside the Engine Control Module (ECM); Intake valve carbon choking or stuck-shut intake swirl flap starving Cylinder 4 of necessary fresh air charge.

P0304 kodu etkinken araç sürmek güvenli midir?

🟡 Dikkat: Koruma Modu Aktif / Servise Gidin

P0304 arıza kodunun tamir maliyeti ne kadardır?

P0304 arıza kodu için tipik onarım maliyetleri kök nedene ve teşhis seviyesine bağlıdır: Seviye 1 (Hafif Onarım / Bakım): 1.200 TL - 3.500 TL: Enjektör soket pini sıkılaştırma, yakıt filtresi değişimi ve kızdırma bujisi iç direnç kontrolü. (Sensör temizliği, yakıt filtresi değişimi, sigorta kontrolü veya kablo soketi temizliği.); Seviye 2 (Parça Değişimi): 7.500 TL - 16.500 TL: Yeni bakır pul ve sabitleme cıvatası ile kaliteli revizyonlu (reman) enjektör değişimi. (Tek bileşen değişimi (basınç regülatörü, dozaj valfi veya revizyonlu enjektör).); Seviye 3 (Komple Revizyon): 35.000 TL - 85.000 TL+: Yeni orijinal fabrika çıkışı enjektör, yüksek basınç borusu ve kurum tıkalıysa emme manifoldu ceviz kumlama (walnut blasting) temizliği. (Yüksek basınç pompası revizyonu, yeni OEM enjektör takımı veya DPF değişimi.). Servis referans fiyatları. Arızaların %70'inden fazlası komple parçalar değiştirilmeden Seviye 1 veya 2 dahilinde çözülür.

Can a bad glow plug cause code P0304 in a diesel engine?

Yes, but specifically during cold starts and the first 3 to 5 minutes of engine warm-up. Unlike gasoline spark plugs which fire continuously, diesel glow plugs only operate during pre-glow and post-glow phases to keep cold cylinder walls warm. If the Cylinder 4 glow plug is burned out, cold compression cannot reach the 500°C auto-ignition temperature of diesel, causing Cylinder 4 to misfire (P0304) and puff white unburned fuel smoke until the cylinder block heats up.

Why does my diesel car misfire on Cylinder 4 under heavy load but idle fine?

At idle, common rail fuel pressure is only 250 to 350 bar, and the injector needs to deliver only a tiny 5 mg micro-pulse. Under full load, rail pressure spikes to 1800+ bar and fuel delivery increases tenfold. If the Cylinder 4 injector has internal control valve wear (excessive backleak) or a partially clogged nozzle, it can deliver enough fuel at low pressure to idle smoothly, but completely fails to deliver the massive volume demanded at 1800 bar, dropping cylinder torque and triggering P0304.

What is the fastest way to confirm whether the Cylinder 4 injector is bad?

The most reliable test is the physical cross-swap. Remove the Cylinder 4 injector and swap it with Cylinder 1 (always install new annealed copper seating washers). Enter the calibration codes into the scan tool and drive the vehicle. If the misfire moves to Cylinder 1 (P0301), you have 100% proven the injector is defective. If the misfire stays on Cylinder 4 (P0304), you know the injector is innocent and must check mechanical cylinder compression.