Rep Power: 241

Hello all, I'm having quite the hard time diagnosing a certain problem with my 03 civic LX. I did a mini me swap for vtec with the Afc neo about 2 years ago and it worked flawlessly. Most recently I had a full port polish and added a crower stage 1 n/a camshaft. Before i had the work done my head went, what was causing the problem was the temperature control motor located behind the glove box and it controls the hot to cold door. ANYWAYS, to make a long story short there are certain afc cables behind there plugging into the ecu and whatnot, when the shop fixed the heat problem, would it be possible that a wire got pulled from the ecu that controls the vtec engagement? Because as soon as i got the car from the shop my vtec was non-existent.... but i thought when you had a mini me swap and the vtec solonoid wasn't connected the car would run in limp mode..?? The neo is in vtec mode and "claims" that it is on and running but i know it is not. Also i've had a cylinder 1 misfire and i have tried tons of things to correct it including swapping the coils and plugs and also a new valve cover gasket and compression test and everything checked out okay. Could the 2 be related or is it just that somewhere in the mix a cable got disconnected or the shop didn't do a proper ecu relearn ( when i started the car after leaving the shop where my heat was fixed the rpms were around 3k at idle and the car wasn't right so i restarted it and everything went back to normal) . Any thoughts?

 
Rep Power: 0

well, vtec head will run without vtec solenoid running properly, it will be gutless, and weak, had it happen on my minime swap, wire came undone, make sure u check the solenoid, could be bad. unless ur using an ex ecu, then u dont have any vtec wires in teh ecu...

 
Rep Power: 241

I'm using the LX ecu, i would change to an EX but i have no idea how to wire that up so.. Anyways, I wouldn't say the car is gutless it feels around the same but when the vtec is supposed to kick in the car doesn't accelerate any faster than normal.. which sucks. I have a wire going from the solenoid through the firewall to the ecu. If i had the EX ecu installed would this avoid the problem, and would vtec kick in more noticably? I have heard it kick in on several different hondas and the sound is 10x more noticeable then the mini me swap

 
Rep Power: 811

i have a civic ex and i dont feel anything when vtec kicks in. its economy vtec, and usually the whole point is to smoothen out the power curve so you DONT feel it switch. also on a stock ex, vtec does not engage unless you are above 4500rpm, at full throttle, and car is fully warmed up with proper coolant temps and oil pressure. having it engage at other conditions could cause engine damage. even then when im looking at the rpm i still dont feel anything. if you have K-series, you can feel it for sure. after hondata reflash, you can barely tell cause the curve is much smoother which is how it should be. there should be a smooth shift between lo and hi hp.

 
Rep Power: 241

Understood, but... I could feel it before, the car pulling harder and the sound deeper, but now that is gone.

 
Rep Power: 811

maybe the afc lost its tune. have you tried resetting the ecu and reprogramming the afc with the fuel trims and all again? alot of times ive seen where the ecu will eventually start adjusting things and makes the tune useless.

 
Rep Power: 241

What could happen if they didn't do a proper ecu relearn ?

 
Rep Power: 0

ecu has nothing to do with it, u lost a connection somewhere, u said apexi neo? does it control vtec engagement? if it does, u need to set it to monitor, to see if vtec is actually engaging. if its not, u need to check wiring to the vtec solenoid, or check the solenoid for voltage...

 
Rep Power: 241

I set it to vtec monitor, and says it kicks on but it isn't, i guess a wire has been disconnected somewhere..i'll have to look behind the dash

 
Rep Power: 0

if its engageing, u need to check the both teh screen on teh solenoid, and voltage at the solenoid, no voltage, means no engagement