Step-by-Step 57 Hemi Spark Plug Wiring Guide with Firing Order Diagram

Begin by confirming the cylinder numbering follows the manufacturer’s standard: driver-side bank as 1-3-5-7 from front to rear, passenger-side as 2-4-6-8. Connect the coil packs in the exact sequence: 1-8-4-3-6-5-7-2, ensuring the ECM processes timing signals without misfire codes. Each coil’s output wire must terminate at the corresponding terminal on the valve cover gasket interface–use a T-pin to verify contact before finalizing torque (11 Nm).

Trace the harness from the primary ignition module: black/orange (BK/OR) supplies 12V reference, while the dark green/yellow (DG/YL) carries the ground return. Cross-reference with a multimeter set to 200Ω; resistance should read 0.5-1.5Ω across coil windings. Deviations indicate corrosion at the PCM connector–clean with electrical contact cleaner and reflow solder joints if oxidation exceeds 0.3mm.

Label each lead with heat-shrink tubing before routing through the firewall grommet to prevent chafing. Secure cables every 15cm using nylon clamps, avoiding sharp edges on the exhaust manifold downtube. The 8mm boots require dielectric grease to prevent voltage leaks–apply sparingly to avoid attracting debris. For post-2010 models, bypass the ASD relay during testing to isolate ignition-only faults.

Test each cycle by grounding a timing light to the harmonic balancer bolt; crankshaft position sensor alignment must show ±2° of TDC on cylinder #1. If random stumbles occur during warm idle, inspect the pink/white (PK/WT) signal wire for intermittent breaks near the intake manifold–replace the full harness segment if insulation brittleness is visible.

Understanding the Ignition Sequence for Chrysler’s 345ci V8

Locate cylinder pairings by referencing the engine’s left and right banks–cylinders 1, 3, 5, and 7 sit on the driver side, while 2, 4, 6, and 8 occupy the passenger side. Begin with cylinder 1 on the front-left, counting backward toward the firewall.

Connect coil packs in this sequence: 1-8-4-3-6-5-7-2. Each coil serves two adjacent cylinders, so verify wire routing to prevent crossfire between pairs like 3 and 4 or 5 and 6.

Use a multimeter to check resistance on each lead–values should fall between 0.5 and 2.0 ohms. Replace any wire exceeding 5K ohms or showing visible cracking, as misfires often stem from degraded insulation.

Mark coil positions with white paint or labeled tape before removal. Many tuners mistakenly swap coils 4 and 6 during reinstallation, causing a rough idle detectable via OBD-II misfire codes P0304 and P0306.

For 2009+ models, note the revised coil design featuring a shorter boot. Earlier models require longer leads; mixing them creates tension that fractures connector tabs, a common failure point after 60,000 miles.

Test the PCM-controlled ignition timing by grounding the diagnostic pin at the OBD port–base timing should stabilize at 10° BTDC ±2°. Deviations exceeding this range indicate either a faulty crankshaft position sensor or incorrect coil sequencing.

Troubleshooting Misfire Patterns

Isolate single-cylinder misfires by disabling fuel injectors one at a time via scan tool. A persistent misfire on cylinder 7 often traces to a faulty coil or a shorted injector harness near the exhaust manifold, where temperatures exceed 400°F.

For intermittent issues, apply dielectric grease to coil boots and spark tower terminals. Condensation buildup in the rear cylinders–especially 3 and 6–accelerates corrosion, requiring annual inspection even if no symptoms appear.

Final Verification Steps

After reassembly, perform a cold-start test. Listen for steady idle and watch for smoke from the exhaust–blue smoke during the first 30 seconds confirms oil fouling, typically caused by reversed coil connections or worn valve seals.

Reset the adaptive fuel trims via a 10-minute key-on, engine-off cycle to ensure the ECU recalibrates around the corrected ignition sequence. Skipping this step risks persistent lean/rich codes despite proper wiring.

Identifying the Correct Cylinder Layout for the Chrysler 5.7L Pushrod V8

Locate cylinder #1 at the front of the driver-side (left) bank–this is the most critical reference point for coil and injector synchronization. The numbering follows a sequential pattern: odd-numbered cylinders (1, 3, 5, 7) occupy the left bank, while even-numbered (2, 4, 6, 8) are on the passenger-side (right) bank. Use a cylinder numbering chart stamped on the intake manifold or a service manual illustration to verify, as aftermarket intakes may omit this marking. Misfiring codes P0302 or P0305 directly indicate cylinder 2 or 5, respectively; trace the coil wire back to the corresponding cylinder head position to confirm.

Verification Methods for Accurate Cylinder Mapping

Disable fuel injectors one at a time by unplugging their connectors while the engine idles–each cylinder should exhibit a noticeable RPM drop when its injector is disabled. Alternatively, use a compression tester with all plugs removed: thread the gauge into cylinder #1’s hole first, then proceed sequentially to #8 while recording readings. Bank sensor locations also help–primary oxygen sensors (upstream) are adjacent to cylinders 1 and 2, while knock sensors nestle between cylinders 4 and 7. If swapping coils, label them with their cylinder number before removal to prevent cross-plugging.

Step-by-Step Ignition Lead Hookup for 8-Cylinder Engines

Locate cylinder #1 on the driver’s side front–the left bank’s lead terminal sits closest to the radiator. Insert the corresponding cable from the coil pack (terminal marked “1”) into this connector, ensuring a firm snap. Verify alignment by matching the wire’s length; the shortest lead should always pair with the front-most cylinder. Skip to the opposite bank (passenger side) and attach the next coil terminal (“2”) to the second cylinder from the front–this maintains the 1-8-4-3-6-5-7-2 sequence specific to Chrysler’s V8 layout.

Rotate the distributor cap clockwise (viewed from above) to expose the next terminal in line. Connect the third wire (coil terminal “4”) to the rear-most cylinder on the driver’s side, then jump to the passenger side’s third cylinder from the back for terminal “3.” Use color-coded sleeves if available–yellow for odd-numbered cylinders, black for evens–to prevent cross-mixing. Tug each connection lightly; vibration can loosen improperly seated boots, causing misfires detectable only under load.

Avoiding Common Pitfalls

Never route leads over exhaust manifolds or sharp edges; use rigid loom or heat-resistant sleeves to prevent chafing. Crossed wires–e.g., swapping positions 4 and 5–will disrupt timing, generating violent backfires or stalling. After completing the circuit, start the engine and listen for smooth idle; irregular pops indicate a reversed pair. For verification, disconnect one wire at a time while idling–each disconnect should produce a noticeable idle drop. If no change occurs, recheck that cylinder’s coil terminal mapping.

Common Mistakes When Routing V8 Coil Connectors

Misaligning the ignition leads with cylinder numbering causes misfires. The correct sequence follows an exact clockwise pattern–starting at the passenger side front, moving toward the driver side rear. Swapping adjacent positions (e.g., #2 and #4) disrupts timing, leading to rough idling or hesitation under acceleration. Mark each terminal with tape before disconnecting to avoid confusion during reinstallation.

• Running cables parallel to exhaust manifolds causes heat damage. Synthetic rubber insulation degrades at 200°C; manifolds reach 350°C during highway driving.
• Tucking wires too tightly against valve covers pinches them–minimum 10mm clearance prevents chafing.
• Using zip ties on sharp edges wears through protective sleeves within 10,000 miles. Replace them with felt-lined brackets or spiral wrap.
• Skipping dielectric grease invites moisture buildup. A pea-sized dab at each boot connection prevents corrosion and tracking.

Route all connectors over the intake manifold instead of crossing the valley. Crossing forces additional bends, increasing resistance and creating parasitic voltage drop–particularly noticeable during cold starts. A single incorrect bend can reduce coil output by 12%. Measure resistance with a multimeter: ideal values range between 6–12 kΩ per lead; deviations exceeding 3 kΩ indicate internal damage.

Neglecting to torque boots to specifications leads to misfires. Each connector must click firmly into the coil tower–8 Nm is standard. Under-torquing allows vibration to loosen connections; over-tightening cracks ceramic insulators. Use a calibrated torque wrench, not pliers. Inspect boots for cracks every 20,000 miles–replace if brittle or discolored.

Essential Equipment for Correct Ignition Lead Setup

Begin with a torque wrench calibrated between 8–15 lb-ft to ensure connectors are fastened without damaging threads or causing misfires. A 5/8-inch deep socket with a swivel joint allows access to recessed cylinder ports, while a 3/8-inch drive extension bar reaches tight engine bays without stripping connections. Use dielectric grease on terminal boots to prevent moisture ingress and corrosion–apply a pea-sized amount to each terminal.

A gap tool set to 0.043 inches validates alignment before installation, though pre-gapped components eliminate this step for most modern engines. Non-conductive pliers or a coil-on plug removal tool prevent accidental shorts when handling live circuits. Keep a roll of high-temperature silicone tape (3M 130C-rated) for securing loose leads away from exhaust manifolds or moving parts.

Specialized Gear Checklist

Tool	Specification	Purpose
Terminal spreader	0.030-inch tip	Adjusts corroded clips
Insulation resistance tester	1000V DC	Detects cracked boots
Thread chaser	14mm x 1.25 pitch	Cleans cylinder head threads
Boot puller	Silicone-lined jaws	Prevents boot tearing

For V8 engines, a magnetic pickup tool retrieves dropped fasteners in hard-to-reach areas. A boroscope with a 1-meter flexible probe inspects cylinder walls for oil fouling before connecting new leads. Store tools in a foam-lined case to prevent nicks that could compromise insulation during future use. Replace any tool showing wear on contact surfaces–even minor abrasions can introduce resistance errors.