just bought a 97 TJ with 180000 miles. I’m gonna do a tune up it doesn’t look like it’s had one in a while. Any suggestions or opinions on what wires and plugs would be the best for it? Thanks in advance!
Suggestions on spark plugs and wires for a tune-up on '97 TJ?
- Thread starter Danny Stephens
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Ask and you shall receive:
What are the best spark plugs for my Jeep Wrangler TJ 4.0?
I'd replace the O2 sensors as part of the tune-up as well. See this thread:
The Official Jeep Wrangler TJ Oxygen (O2) Sensor Thread
With that many miles, a cooling system overhaul should be in the cards a well:
Jeep Wrangler TJ Cooling System Overhaul FAQ
What are the best spark plugs for my Jeep Wrangler TJ 4.0?
I'd replace the O2 sensors as part of the tune-up as well. See this thread:
The Official Jeep Wrangler TJ Oxygen (O2) Sensor Thread
With that many miles, a cooling system overhaul should be in the cards a well:
Jeep Wrangler TJ Cooling System Overhaul FAQ
OE Mopar ignition wires are best. Avoid so-called "low resistance" performance ignition wires. They don't improve performance and they cause static which will be picked up by the computer, AM radio, and CB radio. Resistance is actually added on purpose at additional expense to ignition wires to suppress spark noise (static). Due to the extremely low current in the spark circuit, the added resistance does not significantly lower the voltage delivered to the spark plugs. Ohm's Law and all that.
Three good spark plugs include the 100k mile Autolite AP985 or Champion 3034 platinum plugs, or the 200k mile iridium Autolite XP985.
Three good spark plugs include the 100k mile Autolite AP985 or Champion 3034 platinum plugs, or the 200k mile iridium Autolite XP985.
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I no longer endorse the XP985. I had maybe 16,000km (10,000mi) on these plugs in my 2.5. This engine runs exceptionally well and it start developing a slight miss. Most people wouldn't have noticed but I could tell it was there. Turns out, 3 of the 4 plugs were missing the tiny little iridium ground button off the electrode, essentially opening the gap. Maybe just a bad batch but they looked cheesy right out of the box.
Right now it's running cheap NGK V-powers and doing very well on them.
Right now it's running cheap NGK V-powers and doing very well on them.
What tool did you use to set the gap? The wrong type of gapping tool will damage the iridium coating. Other than that possibility this is the first report ever I've seen of that happening. The XP985 is a very popular and well regarded spark plug, mine are going on ten years old.
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I only use the proper tool. Blue Point with the little slot that contacts the shaft of the ground electrode. Assorted wire ends in specific thicknesses with just a slight pull. Those tiny little buttons are spot welded and something might have been wonky on the assembly line.
I picked up my ignition wires and distributor cap at the dealership, I cant remember the cost but I know it wasnt terrible. I also run champion AP985s, they were all gapped correctly out of the box minus one.