Ford AGSF-32F-MX
Spark Plug

Service and repair of spark plugs should start by taking off ignition coils followed by removal of plugs from the system. Compressed air should be used prior to removal to remove any foreign substances from within the spark plug well. The gap between spark plug electrodes should be checked for deposits that cause bridged gaps due to oil or carbon fouling. Princeipal cleaning procedures for the spark plug must be performed. Sensor oil fouling can be identified by black wet deposits on insulator shell bore electrodes; inspect for this problem since it occurs because oil gets inside the combustion chamber from rings and pistons wear or excessive valve-to-guide clearance or loose or worn bearings; resolve any oil leakage before installing a new spark plug. The presence of black fluffy carbon deposits on the spark plug insulator tips as well as the exposed shell surfaces and electrodes may indicate incorrect spark plug heat range or air cleaner contamination or rich fuel mixture or excessive idling. In such cases one should clean the spark plug. A normal burning pattern will show light tan or gray residues on the spark plug firing tip. The indicator of pre-ignition damage appears as melted electrodes as well as potential insulator damage accompanied by engine-related metallic deposits; this condition may stem from incorrect ignition timing or improper fuel choice or the use of heli-coil threaded inserts instead of spark plugs thereby requiring a new plug installation. A spark plug requires replacement if the technician detects overheating indicated by a white or tight gray insulator with small black or gray-brown spots and bluish-burnt electrodes that can result from engine overheating, the wrong type of fuel, loose spark plugs, spark plugs with an incorrect heat range, low fuel pump pressure or incorrect ignition timing. A visual inspection should also include a check for fused spot deposits that look like bubbles or blisters from abrupt speeding up which requires cleaning the spark plug if found. End the installation process by following the reverse steps of removal while conducting any necessary spark plug gap adjustments.

Inspect the spark plugs and consult the Engine for additional information.

Reverse the removal procedure.

Correct any oil leak concerns before installing a new spark plug.

Look for melted or spotty deposits resembling bubbles or blisters.

Reverse the removal procedure to properly secure the spark plugs back in place.

Inspect the spark plugs and check the spark plug gap, adjusting it as necessary.

Remove the ignition coil-on-plugs.

Overheating can result from engine overheating, the wrong type of fuel, loose spark plugs, spark plugs with an incorrect heat range, low fuel pump pressure, or incorrect ignition timing.

Install a new spark plug.