So I've had this problem for some time now on my project LS1 swapped Rx7, it stumbles and hesitates under load in 5th and 6th. I can bang through gears 1,2,3,4 like a madman but when I'm puttering on the highway and try to do a slight overtake at 40% throttle I get a stumble, than it sometimes bogs with no power. I also get code p0101, but I've already swapped MAF's and tested with a friends. Also I'm getting all the right signals to the MAF. Next I was going to try and swap out the TPS, but since I'm a mechanic I don't usually just throw parts at cars to fix them. Some more info, I did plugs and wires a bit ago, its cammed with full exhaust. Could I use a retune, or because its not all gears is a sensor fouling?

Thanks!

 

Swapped out TPS, still no change. What would make it happen only in 5th and 6th? I read somewhere my AF ratio could be off, possible only at those levels?

 

In my experience a stumble/miss under load at lower rpm's is usually spark related. Since you've already tried plugs n wires maybe swap in your buddies coils ror a test. Qas the dwell messed with at all in the tune?

 

p0101 code should put you into SD mode and you're now relying on only the VE tune which SHOULD be slightly rich unless you've made upgrades (head, cam, intake, exhaust, etc.). In that case, now your VE map is going to be lean and provide not enough fuel. Which will cause a hesitation and stumble. You must clear the code to allow the MAF to function again and get out of SD mode. Also, you might want to tune your VE table since I doubt a Rx7 swapped car is going to work with a stock map.

 

There's a diagnostic/tune forum for this type of t/s. maybe get more responses, there.

 

Check out your map sensor.

 

Why would this cause a P0101 DTC? TIA

 

you need to to log it when it's acting up to actually see what it's doing. If not you are just going to be replacing parts until you get lucky.