Quick run down. It's a 2008 with the V6. I've owned it for 5 years. It had 95k when I got it and has 215k currently. Always ran fine. Couple weeks back I disconnected the battery to clean around the posts. It idled a bit rough (under 500 rpm) but I figured the computer will re adjust. It still idles a nut rough and now instead of getting 300-350 on a tank of gas, I'm getting 200-250. Any ideas what it could be?
Rough idle and reduced fuel economy. Any ideas?
- Thread starter DanielW
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ZebRuaj
New member
Whoa. OEM V6 spark plugs are coppers rated for only 30k. If you last replaced with copper NGK/Denso's, you're waayyyyy past due.
theoutbackdream
New member
Literally spit my drink out. You're way over due! get some spark plugs ASAP!
Bossman
Senior Member
Spark plugs most likely need replacement ... for the win!
http://www.toyota-4runner.org/4th-gen-t4rs/122218-changing-spark-plugs-2008-v6.html
http://www.toyota-4runner.org/4th-gen-t4rs/85813-2008-4runner-4-0l-spark-plug-diy.html
http://www.toyota-4runner.org/maint...v6-1gr-fe-spark-plug-change-instructions.html
http://www.toyota-4runner.org/4th-gen-t4rs/122218-changing-spark-plugs-2008-v6.html
http://www.toyota-4runner.org/4th-gen-t4rs/85813-2008-4runner-4-0l-spark-plug-diy.html
http://www.toyota-4runner.org/maint...v6-1gr-fe-spark-plug-change-instructions.html
Montego Murph
Member
Er, I *hope* that's what's going on with my '03. Even the dash-mounted lie-o-meter is saying "15.8" so that means I'm getting 13ish in real life.
benztech82
Member
Try to recalibrate your ECU by simply disconnecting your negative battery cable for 30 sec. Then start the engine with all accessories off a/c heater, everything off. Let it run for 10 min do not press accelerator during this time. Also it may start funny or die at first start, just restart it and wait 10 min it should normalize. If that won't help start looking at basic maintainer items.
2005 V6 LTD 186k
2005 V6 LTD 186k
Supersonic
New member
Mine had a reduction in fuel economy and I had recently removed the air box 2nd filter because it had 294k and there is no replacement part. I also replaced the PCV with an after market $3.99. Yesterday it occurred to me it might be a deficient PCV in that it is not metered right for whatever reason.
So I cleaned the old one, 30 minutes in Seafoam and sprayed it out with carb cleaner while waiting on a new, better priced one from eBay. Don't know the result yet, but I just got it replaced.
I also cleaned the Mass Air Flow Sensor and tried the alternative one I had available. Because the 2005 Matrix has the same Denso replacement part number because I figured they would be interchangeable and had about the same result, mostly positive fuel trims no long or short term above above 10 but nearing, and ~18 miles to the gallon per meter.
I did erase the codes and that reset 16 Toyota Readiness (enhanced)codes and all of them cleared now except P0300, p0100, p0102, and p0103, which the last 3 point at the MAF. Being I had the spare Matrix MAF result, I ordered an inexpensive ~$16 eBay Replacement just to see if they are of any quality, I don't think the original is bad.
I have new vacuum hose assortment but the cooler weather hasn't cooperated with my motivation levels. The larger vacuum hoses on the PCV and intake did seem loose, so I ordered new PCV and currently have a substitute because it's a molded hose and that's what I want back on it.
So I cleaned the old one, 30 minutes in Seafoam and sprayed it out with carb cleaner while waiting on a new, better priced one from eBay. Don't know the result yet, but I just got it replaced.
I also cleaned the Mass Air Flow Sensor and tried the alternative one I had available. Because the 2005 Matrix has the same Denso replacement part number because I figured they would be interchangeable and had about the same result, mostly positive fuel trims no long or short term above above 10 but nearing, and ~18 miles to the gallon per meter.
I did erase the codes and that reset 16 Toyota Readiness (enhanced)codes and all of them cleared now except P0300, p0100, p0102, and p0103, which the last 3 point at the MAF. Being I had the spare Matrix MAF result, I ordered an inexpensive ~$16 eBay Replacement just to see if they are of any quality, I don't think the original is bad.
I have new vacuum hose assortment but the cooler weather hasn't cooperated with my motivation levels. The larger vacuum hoses on the PCV and intake did seem loose, so I ordered new PCV and currently have a substitute because it's a molded hose and that's what I want back on it.
Montego Murph
Member
Make a note that you'll have to reset your rear window/wiper/defroster afterwards!
The plugs were definitely in need of changing. I don't know why I thought they were good for 100k miles. Will change them at 30k now. The problem still persists. I refueled on Sunday and did about 90 miles and the tank is already almost at half empty. Do I need to reset the ECU after doing plugs?
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Montego Murph
Member
I say it couldn't hurt for reasons of pure science and diagnostics -- you'll then be starting each improvement with a new baseline/clean slate/whatever you want to call it.
If the ECU was compensating elsewhere for fouled plugs, you'll want to let the ECU know that the situation (likely higher resistance) in the ignition department has been resolved.
