I've had this issue now for about 2 months. Replaced my wideband o2, spark plugs, coil packs,fixed my overheating motor issue, swapped in a new tps,new map sensor, relocated the IAT sensor and have had three tuners look and my tune and datalogs to see if it was the tune and to see if the sensors were working or not. They work fine. What happens is while appling throttle the car would cut out randomly here and there(similar to a tps issue). But only when the engine is hot. Last night at the track I rewired my AEM 320 e85 pump right to the battery using some 10 guage wiring with an inline 30 amp fuse and 30 amp relay. Today I will be throwing some injector cleaner in the tank to see what happens. Anyone else know what could be causing this?

Thanks!

 

The car also goes to full rich when this happens and injector cleaner doesnt seem to be helping

 

what throttle range and rpm ? with my baffles out i get a little roughness in the 3200-4000rpm range at 25-35% throttle i have vtec set at 3300 rpm and 40% throttle the high cam gets rid of it and a custom catalytic converter or baffles in a large exhaust that seems to be a biggie with the air to air i am running 70mm with same size test pipe when i can afford it i will buy a champ car cat and build a converter to put up with high boost and rich conditions without melting down only problem is there around 600 $ us

 

At like 15% throttle around 3k rpm

 

yes once i added some back pressure it seemed to cure it as well as the second bov

 

But my car goes to full rich and almost fully lean while partially on the throttle

 

I have a very similar issue... CT exhaust with a test pipe 11psi, 1 blow off valve. My issue is often when I shift, when I go to get back on the throttle it has 0 response. It also happens sometimes under partial throttle

 

I have a PLM header, Berk 70 HFC and invidia Q300. Are you saying that a 70mm exhaust might be causing it? I find if weird cause it only happens when the engine is hot. My Vtec is set at 4100rpm. I dont really want to lower that either...

 

it could be in the breakpoionts in your map or accel tables if you can run a sceond bov i would . i don't have any hesitation unless i get very low on fuel but that's normal

 

I've had 2 different tuners take ride along with me while data logging and they both said its a mechanical issue and not related to the tune. We checked voltage at the tps ans it was reading around .9 so we had to file the slots bigger an got down to .5V. That helped a bit temporarily until the next day. I ended up putting another bov on the hot side with 3 or 4 psi spring. Drove 3 hours to the track. Only got about 6 laps for the day due to this "fuel cut" issue. I ended up buying a 30 amp relay and fuse and hardwiring the pump to the battery using 10 gauge wire. This problem still persists. I have an omni power tps coming in tomorrow so I will be trying that out and will check the fuel pump filter and hose clamps.