Loss of power after 4k

[88stang88]

So i have a 95 Gt that is a stock and automatic car and just did some work thats required after so many miles are put on the car. Currently the car is sitting with 96k miles and replaced the harmonic balancer at 90k when it went out. Just replaced the water pump less than 200 miles ago and now since i've replaced that i have no power after 4000 rpms it will pull fine up to then but when its in the 4000-5500 range it just stays there and car loses the pull and wont shift out like it use to. However if i manually shift it thru the gears it shifts,still no power...and this wasnt the case before the water pump went out,now when you get on it,it throws a check engine light for about 10-15 seconds and it goes away. Has anyone experienced this problem before or have any knowledge on the cause?

 

[302GTS]

Experienced this a couple times. Clean the MAF sensor really well. I just use carb cleaner and a qtip. Spray the filaments down with carb cleaner, and rub with a qtip until the resulting qtip is dry and clean. If this doesn't help, which it sounds like it should since you're throwing a code, try changing spark plugs. I learned from here that having platinum plugs in my car from the previous owner causes the car to break up and not pull much past 4k rpms when they're old. Swapped them out for a set of Autolite coppers, and the problem was solved. Check that MAF first thing though, as I had the same issue when I first bought my car!

 

[88stang88]

Ya i figured it was something with spark or air/fuel just had alot on my mind recently and didnt have my thinking cap on. I will be doing some plugs and wires on this beast soon...just been working on a buddies z28 he bought he has been having more issues than me which isnt suprising...

 

[302GTS]

Poor f-body owners...

That MAF should fix this issue. When my spark plugs started getting old, it didn't throw any codes. When my MAF was dirty, it threw an occasional code. Cleaned it up, and havn't had the problem since!

 

[88stang88]

Ya it only throws the code if your over 2500 rpms. Weird..

 

[302GTS]

Yup!!! Mine did the exact same thing. Definitely clean up that sensor. Takes no more than 10-15 minutes, and the car will pull beautifully after it's done.