SO I bought a 90 Civic Dx hatch with a OBD0 b16a motor swapped into it, just a beater to get me around, it has a problem that when you first start the car, it will idle fine, maybe a little miss here and there, but pretty nice

When you rev it, with no load, it will rev up fine, but seems to be breaking up quite bad until you hold at a steady rpm then it will sit there fine

If you try and start the car and just start driving, wotn happen, the thing putters and backfires and the rpms wanna fall fast, you can rev yourself out of it and once the rpms get a little higher it seems to move

You can drive let it warm up for 5 min and itll drive off just fine without a stutter in the world

Or if you cold start it and just drive it takes about a minute for it to stop wanting to die.

Like literally die, just stops accelerating and starts puttering then itll randomly jump back to life

I changed the plugs because they were mismatched and old anyways, dont want to spend to much money on this.

Hope maybe someone has had this before

Thanks

 

I should also mention I get **** poor gas mileage.

E-test showed me ***** rich on the 25mph test

 

 

Sounds like it could be electrical. I had the same issue with my civic, and it was a plug wire. Sheck the resistance on them, and replace if nessecary. check plugs etc.. as well.

 

bump

 

could be a idle air control valve problem not giving the engine more air to keep it running - is it missing or just cold blooded

 

i say a distributor issue... there are no codes ?

 

Its missing, you can hear it misfiring and just sounds all puttery and popping out of the exhaust, quiet, but making noise until the rev SHOOT out of knowwwere perfectly