Ignition Coil and Spark Plug Replacement for 2000-2002 Lincoln LS ($ Jaguar S-type) 3.0L V6.
Ford/Lincoln/Mercury misfire, but no check engine light.
Do you feel a misfire, but no check engine light? The Ford/Lincoln/Mercury system is designed to show a check engine light if the misfire is above 2.3% of the firing cycles. If it misfires less than 2.3% of the firing time, it will record the misfire in the PCM, but will not illuminate the check engine light.
To find this misfire using a capable scan tool for Ford/Lincoln/Mercury vehicles. Follow these instructions. If you don't have a scan tool, you can go to your local auto part store, and ask for a scan. Give them these instructions:
Turn the key to the "ON" position, but do not start the vehicle. The lights on the dashboard should be ON, and the engine should be OFF. Plug the scanner into the OBDII port. Follow the directions on the scanner and go into the "non continuous monitors" function. Some scanners may have this as "diagnostic monitors", or different names, so keep this in mind.
The Test ID is different depending on the model year.
$51 - 1996-1997 MY
$53 - 1997-2006 MY
$81 - 2007+ (CAN bus)
- On your scanner, select Non-continuous monitors. Some scanners will have this named something else like "diagnostic monitors", etc.
- Select Test ID $51 for 1996-1997, Test ID $53 for 1998-2006, and test ID $81 for 2007+
- Here you can see the actual computer reading of the misfire. Because it is in converted hexadecimal language, you will see the $ sign often. (Component $01 = cylinder 1, Component $02 = cylinder 2, etc) "Value" is the misfire count. The value should be very low or 0. The cylinder with the highest value is the one causing the slight surge/hiccup/misfire.
From there you can check the specific cylinder (coil, spark plug and connection) to see what's causing it. Also make sure to check for unplugged vacuum lines, and a faulty fuel pressure regulator. Those are also issues that may cause a misfire in any cylinder. If you don't see anything visibly wrong with the cylinder, then you can do the ignition coil swap method. You do this by swapping a coil from the misfiring cylidner over to another cylinder. Once it's swapped over, reset the PCM (PCM = power train controle module AKA main computer) with your scanner, or by disconnecting the battery for at least 1 minute. Drive your Ford until it starts misfiring again and re-scan. We do it this way to allow the PCM enough time to identify the new misfire location. If the code follows the bad ignition coil, then you know for sure that you have a bad ignition coil. If the misfire remains on the same cylinder, then you have just narrowed the problem down. You could have a bad fuel injector, spark plug, cam or crank sensor, MAF sensor, or a damaged connector or wire harness/ bad PCM. Worst case scenario will be internal engine damage.
Pictured below are Ford 2v & 3v 4.6L and 5.4L V8 cylinder numbers, and Ford 2v & 3v 6.8L V10 cylinder numbers.
Misfire codes are typically:
- -P0301 Cylinder 1 misfire detected
-P0302 Cylinder 2 misfire detected
-P0303 Cylinder 3 misfire detected
-P0304 Cylinder 4 misfire detected
-P0305 Cylinder 5 misfire detected
-P0306 Cylinder 6 misfire detected
-P0307 Cylinder 7 misfire detected
-P0308 Cylinder 8 misfire detected
-P0309 Cylinder 9 misfire detected
-P0310 Cylinder 10 misfire detected
Other Codes related to a bad ignition coil, but not as common with Fords
- -P0351 Ignition Ignition Coil A Primary/Secondary Circuit Malfunction (Cylinder #1)
-P0352 Ignition Ignition Coil B Primary/Secondary Circuit Malfunction (Cylinder #2)
-P0353 Ignition Ignition Coil C Primary/Secondary Circuit Malfunction (Cylinder #3)
-P0354 Ignition Ignition Coil D Primary/Secondary Circuit Malfunction (Cylinder #4)
-P0355 Ignition Ignition Coil E Primary/Secondary Circuit Malfunction (Cylinder #5)
-P0356 Ignition Ignition Coil F Primary/Secondary Circuit Malfunction (Cylinder #6)
-P0357 Ignition Ignition Coil G Primary/Secondary Circuit Malfunction (Cylinder #7)
-P0358 Ignition Ignition Coil H Primary/Secondary Circuit Malfunction (Cylinder #8)
-P0359 Ignition Ignition Coil I Primary/Secondary Circuit Malfunction (Cylinder #9)
-P0360 Ignition Ignition Coil J Primary/Secondary Circuit Malfunction (Cylinder #10)
DID YOU KNOW:
A basic OBDII scanner can be purchased online for between $10 and $20? You can also get a Mode 6 scanner starting at around $50 online? We don't sell these (yet), but we are happy to recommend any place who offers these at a great price. Ask us for recommendations if you are unsure where to go. You don't even have to work on cars to benefit with one of these devices. You can scan your vehicle before you take it to the mechanic, and walk into the mechanic shop or dealership with knowledge, or maybe your check engine light is on for a fuel cap. This is priceless.
