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How Many Miles on your FX35/FX45

55K views 38 replies 28 participants last post by  drdaj  
My 04 RWD has 256000 and still running great. It burns oil but it's manageable. I've had a lot of the most common issues mentioned throughout the forum that I've had to repair myself with little to no money:
  • Had a major oil leak when I bought it 5 years ago
    • fixed by replacing both valve covers bought on eBay for $80. (This also fixed the burnt oil smell during idling)
  • slip/vdc light with sudden hard gear shifts (fixed by polishing ground connections throughout the engine bay),
  • Error codes P420 & P430 for catalytic efficiency below threshold. Only a problem at annual emissions inspection:
    • To pass emissions tests: I used a $15 Bluetooth OBD2 from Amazon to clear the Error codes, then closely monitor the ECUs emission tests status with any decent free OBD app. After all the tests pass, go do the inspection asap unless the check engine light turns back on. (the catalytic errors take a few more days to come back.)
  • Annoying metallic rattle most noticeable in drive-thrus or during hard acceleration (fixed with $2-3 per worm gear hose clamps to hold loose exhaust pipe's covers)
    • To my surprise, after doing this fix 2 years ago, the catalytic error codes mentioned previously went away permanently. My guess is that because oxygen sensors can be very sensitive to vibrations, the excessive rattling from the exhaust pipes somehow affected the readings.
  • Transmission started slipping when accelerating from a stop if at minor inclines. After worsening, was quoted $1200 for a transmission rebuild.
    • (Fixed by adding oil up to spec)
    • It is really difficult to have a reliable measure of AT oil level at the various temps described in the FSM. Without access to the AT oil temp sensor readings, the marks on the dip stick are meaningless.
    • Used a multimeter's temp probe that was small and with a long cable that fit in the dip stick tube
  • Oil in 3 of the spark plug tubes closer to the firewall. One of the valve covers' spark plug hole rubber gaskets had a hole, some of the others were beginning to crack.
    • To avoid replacing the valve covers again, I use the old ones as a guide (rubber gaskets were in worse shape) to mentally map out where the blowback gas passages were. My goal was to inject as much Permatex Black one minute gasket (chosen because it expands a little vs the original) as possible into the tube seals, but not so much that it blocks the gas passages.
    • Only removing the ignition coils was needed to work. Make sure to apply the gasket maker between the rubber seals and the metal of the spark plug tube and inside the cracked or broken seals. Finish it off with your fingers or a small rag to name sure there are no air gaps between the tube and the upper and lower ends of the rubber seal.
I've browsed these forums for years but this is my first post, and all of the 'fixes' above were also the first time I've attempted them. Hopefully I can give back a little to the community!