I have a 91 civic hatchback with a b16 dohc vtec, when the vtec kicks in when the car is warm, it bogs down instead of kicking me back with the boost of 20-30 hp.

Im not throwing any check engine lights...

Any help would be greatly appreciatied....

 

is it a dpfi to mpfi car?

 

its a b16 swap from an si, si I guess no went to mpfi to mpfi.

 

Ill help as much as i can. Vtec is basically not kicking in 'duh'. When i had hooked up mine to a apexi safc neo and forgot to turn on vtec engagement, it actually kept the solenoid completely off. Dont try to mess around with yuor car too much like that, and dont manual engage the vtec, lean machine. look at yer ecu and see if you dont have the solenoid hooked up right and or sensor. Chekc to see if your coolant temp is reading correctly and make sure that the ecu wires arent dmaged for the coolant temp. OR you may have the solenoid hooked bakwards and vtec may be hot all the time and disengaging when its supposed to engage. Just look for backwards screw ups.

 

I can here it kick in the vtec solinoid, the fan was running all the time when start car, I just fixed that.

It has a PR3 ecu.

 

also im being told to check fluids but all are fine, I was told to take off valvecover and inject some oil into the vtec solinoid with a syringe?? what do you think..

 

Also I want to know if someone has pics of a swap done..

 

one time my buddy put a b16 in his eg hatch witch had the smallest exhaust on it
cuz it was the 70hp model and it would bog down super hard when vtec hit but
drove fine untill 5500. then we ran it straight header... it ran perfect. his wiring
was perfect tho keep that in mind. always chck wiring first.

 

It has the stock si tubing, I just ordered a new exhaust becuase I looked under the car and it was being held on with wire but will be all good in a couple of days..

 

this might sound stupid to most but just try it.
i had the same problem with my crx when it was b16 and it ended up being my tps sensor. if it was connected, as soon as vtec was supposed to crack it would bog down like crazy. with it disconnected the car ran fine.

when i swapped my b16 for b20 i thought i wouldnt have that problem anymore since the b20 is non vtec, but instead it would bog down as soon as i punched it...so my tps sensor is disconnected at all times and its been running fine, must be something in the wiring.

 

it runs fine now. The map sensor was sucking in air.. fixed now kicks in fine, just hear the vtec solinoid kick in now...

 

I FOUND MY PROBLEM! Loose ground on TPS. Thanks Guys!

 

Sorry wrong thread

 

Hey guys, i'm new here.
I don't think its much off topic so here goes.

I have a d16y5 engine on an ek sedan which bogs at 5000 rpm. I've changed the fuel pump, filters (air, fuel and oil) new oil, plugs and distributor and yes no CEL codes.

all stock save for SRAM (recently cleaned element) intake and apexi muffler.

Out of frustration, tried to disconnect the vtec solenoid socket and tried it out. Surprisingly, it did reach the red line. (CEL was on)

I reconnected the solenoid, reset the ECU and again no codes.

I'm stumped.

BTW, i also changed: Engine temp sensor (the one below the distributor) and IACV recently. tried the MAP sensor of a friend as well.

In terms of drivability and power (before 5000rpm) its great. its just really irritating for the engine stop revving at 5000 rpm.

Please help!

oh and one more thing. this is my original motor. no swaps at all.

 

you fail

 

Just for the info of everyone. I solved this issue already.

1. replaced dizzy o-ring
2. resealed vtec solenoid gasket (strainer was clean)
3. Crankshaft pulley to 0BTDC/ camgear to TDC (Honda manual says that drive pulley to TDC in such case would cause crank pulley to move to 18 BTDC
4. adjusted valve lash IN (0.08) EX (0.10)

now running extremely well.

 

So how did u fix the map sensor? Cuz my car is bogging too right web vtec is about to engage it Boggs a litto then vtec kicks but not all the way. Did u just buy a new map sensor?