6th Gear Performance Issue
Thread Starter
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
6th Gear Performance Issue
It use to be that in 6th gear, I had good throttle response and power once doing 75mph and above. Lately, what I feel is about 1/2 throttle, it responds this same way nicely but pushing farther on the throttle, it accelerates slowly almost like the old days when an engine would be running too rich or too lean.
I replaced the front O2 sensors yesterday which made no change. I'm considering going out there right now and plugging the pcv to intake connection and see if it improves. No codes are present. I'm still on the original fuel pump so maybe its getting weak but I have no fuel pressure meter to connect. If the cats were partially plugged, I would think anything blocking the inlet screens to them would be burned out real fast. Yes, air filter is clean and I cleaned the maf again too.
Looking for thoughts.
I replaced the front O2 sensors yesterday which made no change. I'm considering going out there right now and plugging the pcv to intake connection and see if it improves. No codes are present. I'm still on the original fuel pump so maybe its getting weak but I have no fuel pressure meter to connect. If the cats were partially plugged, I would think anything blocking the inlet screens to them would be burned out real fast. Yes, air filter is clean and I cleaned the maf again too.
Looking for thoughts.
Team Owner
Joined: Mar 2001
Posts: 21,325
Likes: 3,840
From: small town in S.E Pa. PA
St. Jude Donor '03-'04
I think you are missing something here... we designed the MN6 with two overdrive gears: 5th and 6th, these were never meant for power or performance.. so dont look for them.. both gears are less than 1:1 and were put there specifically to get you that 32/33 mpg. If you had a problem with your car, the car would tell you so... So dont look for problems that arn't there... if you notice some slugishness, chalk it up to less dense warmer air now that spring is here.. and it's more noticable in 5th and 6th gear.
Thread Starter
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
No, this is the car with currently 308K on the clock and up until the past couple of months, the performance that I speak of was there. I'm the only owner of this car. It seems that mileage dropped off a little as well. Of course I never expect it to blast off down the road in 5th or 6th gear but I know a loss of performance when I feel it.
Racer
Joined: Mar 2006
Posts: 373
Likes: 0
From: Belews Creek N.C.
I think you are missing something here... we designed the MN6 with two overdrive gears: 5th and 6th, these were never meant for power or performance.. so dont look for them.. both gears are less than 1:1 and were put there specifically to get you that 32/33 mpg. If you had a problem with your car, the car would tell you so... So dont look for problems that arn't there... if you notice some slugishness, chalk it up to less dense warmer air now that spring is here.. and it's more noticable in 5th and 6th gear.
How does it runs 1st through 4th?
Thread Starter
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
1st through 4th are fine but its hard to tell. I did do something today that has made a difference. I got into the computer, downloaded the PCM using LS1Edit and found the Main and Sec VE Fuel tables had errors in them as well as the High and Low Octane spark tables. I fixed all of them, uploaded the changes then drove it. Feels better. I'll know after about a week of driving it, if it really made a difference or not.
