Opinions on FIPK & MPG loss
#1
Opinions on FIPK & MPG loss
2001 Silverado ECSB 2wd 5.3L 4L60E, no codes read from Scangauge II.
My pops drove this truck from 1500 thru 90k. His driving was 80% hwy miles, so he was always looking to improve his mpgs. Along the way he bought a K&N FIPK hoping to help out mpg but he noticed a MPG loss on the highway, 2-3 mpg. So he took it off, put back on stock box and away he drove.
So I bought this truck from him for cheap @ 90k. It has always ran very strong, getting 20 mpg on the hwy pretty easy, sometimes 21. At some point I grabbed the FIPK off the shelf and installed it. Throttle response was a little better and the sound was pretty cool, but I too noticed a 2-3 mpg loss.
What gives? Everyone says these gain mpg, hp, throttle response, etc... Intakes on these motors are supposed to be great! I still drive with the FIPK on for right at a year now and still have never gotten above 17.5mpg on the hwy since. In the past 4 months, I have gotten a Nelson mail order 91 octane tune, hoping to regain some MPGs. The truck responded great, so much more power, better shifting, everything is great with this tune, I love it, but still not more than 17.5 MPG on the hwy??
Any ideas guys? Do I need to get a wideband and see if this thing is running rich, eating my gas?
Thanks for any response. I did some Google searching and not many (any) people have this problem with K&N FIPK.
My pops drove this truck from 1500 thru 90k. His driving was 80% hwy miles, so he was always looking to improve his mpgs. Along the way he bought a K&N FIPK hoping to help out mpg but he noticed a MPG loss on the highway, 2-3 mpg. So he took it off, put back on stock box and away he drove.
So I bought this truck from him for cheap @ 90k. It has always ran very strong, getting 20 mpg on the hwy pretty easy, sometimes 21. At some point I grabbed the FIPK off the shelf and installed it. Throttle response was a little better and the sound was pretty cool, but I too noticed a 2-3 mpg loss.
What gives? Everyone says these gain mpg, hp, throttle response, etc... Intakes on these motors are supposed to be great! I still drive with the FIPK on for right at a year now and still have never gotten above 17.5mpg on the hwy since. In the past 4 months, I have gotten a Nelson mail order 91 octane tune, hoping to regain some MPGs. The truck responded great, so much more power, better shifting, everything is great with this tune, I love it, but still not more than 17.5 MPG on the hwy??
Any ideas guys? Do I need to get a wideband and see if this thing is running rich, eating my gas?
Thanks for any response. I did some Google searching and not many (any) people have this problem with K&N FIPK.
#3
11 Second Hall Moniter
iTrader: (22)
At that mileage, I'd replace the spark plugs & fuel filter, clean the MAF sensor, and maybe even the front O2's. That should bring back your MPG's.
I doubt that it has anything at all to do with the air cleaner/intake tube. Any slight difference in the airflow would be taken care of with the PCM fuel trims, if the tune up is good.
I doubt that it has anything at all to do with the air cleaner/intake tube. Any slight difference in the airflow would be taken care of with the PCM fuel trims, if the tune up is good.
#4
Thanks for the reply, thats what I thought too. BUT this has happened for 2 different people at two different points in the trucks life, with the same MPG loss, immediately after the K&N. And when my dad switched back to stock airbox, he regained MPG.
I have changed plugs & wires, originals looks great, cleaned the K&N filter and LIGHTLY oiled, cleaned MAF multiple times, cleaned throttle body, checked ERG valve. I have wondered about the O2s but havnt done them, I figured they would throw a code if they were bad. Maybe I should look into the O2s....
I have changed plugs & wires, originals looks great, cleaned the K&N filter and LIGHTLY oiled, cleaned MAF multiple times, cleaned throttle body, checked ERG valve. I have wondered about the O2s but havnt done them, I figured they would throw a code if they were bad. Maybe I should look into the O2s....
#5
12 Second Club
iTrader: (1)
I have changed plugs & wires, originals looks great, cleaned the K&N filter and LIGHTLY oiled, cleaned MAF multiple times, cleaned throttle body, checked ERG valve. I have wondered about the O2s but havnt done them, I figured they would throw a code if they were bad. Maybe I should look into the O2s....
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#8
I replaced the fuel filter at the same time as the K&N install, then again when the fuel pump crapped out this winter. I also seafoamed it a while back, in gas tank, in oil and intake. I also did the water decarbon trick. I don't think I had much carbon build up, but when I changed the oil after about 100 miles with seafoam in it, it was like chocolate. Worst oil I've ever seen from this truck. It's had Mobil 1 synthetic since 30k.
Maybe the O2s will help out. Would it be worth doing a wideband while I'm doing it?
#9
I did not trim the air box below the K&N cone filter. There is a pretty big hole in it already, I felt. When I cleaned the K&N & reoiled, I let the oil sit overnight to wick. I also oiled as lightly as I possibly could. And I cleaned the MAF, and cleaned again a few weeks after the air filter clean & re-oil. The MAF is not descreened. I have run Lucas injector cleaner through the fuel system also, in addition to Seafoam.
I used to get 14-16 in town, now I'm at 11.5 mpg.
I used to get 14-16 in town, now I'm at 11.5 mpg.