high rpm while driving
#1
high rpm while driving
hey guys, I posted this problem before thinking it was possibly my high flow cat causing this problem of having my rpm stay near 2000 while cruising around 50 mph.
for all the 4.7ls out there you know normal at 50 mph is more like 1400 rpm. the rpm stays high only when cold outside. any ideas why this is?
after about 5 miles of driving or so she drops back to normal rpm when I'm at speed.
So basically this is what she's doing:
Cold morning, shes been sitting over night in a garage. cruising speed is around 50 mph and rpm is around 2000.
After about 5 mins (realistically 5 mins) or 4-5 miles of driving she starts to act normal. mostly...
Any ideas guys? when shes cold her rpm are high. once the engine is warmed up some she acts better.
I'm getting around 10.5-11.0 mpg right now instead of my usual 12.0-12.5 mpg or so in the winters. which has put a big sore on my wallet.
thanks guys.
for all the 4.7ls out there you know normal at 50 mph is more like 1400 rpm. the rpm stays high only when cold outside. any ideas why this is?
after about 5 miles of driving or so she drops back to normal rpm when I'm at speed.
So basically this is what she's doing:
Cold morning, shes been sitting over night in a garage. cruising speed is around 50 mph and rpm is around 2000.
After about 5 mins (realistically 5 mins) or 4-5 miles of driving she starts to act normal. mostly...
Any ideas guys? when shes cold her rpm are high. once the engine is warmed up some she acts better.
I'm getting around 10.5-11.0 mpg right now instead of my usual 12.0-12.5 mpg or so in the winters. which has put a big sore on my wallet.
thanks guys.
#2
Sounds to me like you could have some crud on your O2 sensors, I'd recommend unscrewing them and taking a torch to them to burn off the suspected residue. Also it sounds like you could have a bad TPS (located on driver side of TB).
I'd take a reading from it and it should be in the ballpark of .70 to .75. Anything higher than .78 I'd suggest replacing it.
I'd take a reading from it and it should be in the ballpark of .70 to .75. Anything higher than .78 I'd suggest replacing it.
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#10
That sounds like great news to me! cant wait til its 60 degrees and i can just throw on a hoodie and roll my windows down and roar past people. gotta love the fall/spring season. not to hot not to cold. i'm tired of minnesota weather. it gets as cold as -20 degrees AIR TEMP and as hot as 100 degrees with humidity.
thats to much for me.
edit: just checked and it says in Minnesota it can get as cold as -60 degrees below (with windshield i'm hoping!!!) and as hot as 114 degrees. both numbers seem far-fetched.
thats to much for me.
edit: just checked and it says in Minnesota it can get as cold as -60 degrees below (with windshield i'm hoping!!!) and as hot as 114 degrees. both numbers seem far-fetched.
Last edited by ajoshi91; 02-08-2011 at 09:49 PM.