2008 LR3 4.4 140,000 miles

I wanted to get some feedback from anyone who has replaced all the spark plugs. Did they see a noticeable difference.

I’m helping a friend get his just purchased LR3 ready for state inspection.

We we’re getting misfire on cylinder #1 and replacement coil and spark plug solved that code.

We have cleared the check engine codes and cleared the ECU adaptive reset.

It has not been driven enough to pass the smog test but the engine seems to not be running smooth.

We are thinking the next step may be replacing all the spark plugs. Inexpensive and with the miles it may be time to do it anyway.

 

if the code hasn't returned, you may not need a next step.
plugs should have been done at 90k - do you know if they were?

maybe just drive enough to get the monitors "ready" for smog and go from there.

 

we don’t know if the plugs were changed.

Car fax shows service but no details.

I even called one of the dealers but all records after four years are deleted.

My guess is the second owner did little service

 

I'd agree to stop until it passes emissions, then move on with additional maintenance.

Always a good idea in my opinion w a new vehicle to change the plugs if you don't have records of it being done. Some more drivetrain & electrical items for your list could include:

• transmission drain & refill w new filter and updated pan - definitely the biggest job on the list and the refill *must* be done properly, but this is really important and often neglected
• of course oil/filter change, and diff fluid change for front and rear
• air filter if it looks like it needs it
• clean the maf w maf cleaner (gently!)
• check / clean the throttle body - must reset fuel adaptations afterwards to initiate throttle body position relearn
• new oem pcv valve
• clean and check all vehicle and engine grounds, including the negative cable, engine to chassis ground etc
• stress test the battery and replace if it's not 100%. LR3s chew up batteries every 2-3 years and a weak battery can cause all sorts of mischief
• replace brake pedal switch with a new Motorcraft one
• replace all rear brakelight bulbs w oem or oem equivalent - brake switch and bulb issues can also cause all sorts of electrical gremlins
• get rid of the coolant bleeder t valve or replace with a brass version - fill up the attached hoses with coolant before reconnecting so you don't need to bleed the system
• the thermostat housing is another weak point that you'll want to check for age/cracking/leaking and replace with oem at some point

I'm sure I've forgotten something important, and others here can add to that list, but those are top of mind for me with a new-to-me LR3.

 

There's a also a collection of points that can often leak water and cause big electrical headaches. These include the front sunroof drains, the windshield cowl and under the front A pillar trim pieces. Good to inspect and address those asap as well. You can find plenty of info here on the forum about those.

 

Thanks everyone....I got my LR3 almost 2 years ago and it seems I've experienced all the known issues getting it back in order from where it was when I purchased it.

For my friends LR3 the misfire on #1 has come back. It has not really been driven, just starting it up and moving it out of the garage to work on in the driveway.

We have a new issue that may shine light on our problem. While waiting for it to get up to operating temperature the engine cut off when the coolant was around 145 degrees Fahrenheit.

Again, main issue is rough idle, misfire on cylinder #1 even after swapping in a different spark plug and coil. The LR3 is from unknown past owner so we have little to go on. He got if for a very good price so we knew we would be going down this road of diagnosing issues.

Flyer08 seems to may have a similar issue so I'm keeping my eyes on that thread as well.

Thanks