SOHCgirl

Hi everyone, please help me if you can. Yesterday, my 1996 civic ex manual trans developed a SUDDEN issue. Earlier in the day I thought I felt a surge while driving but I had the AC on and it always drives funky when it's on so I ignored it. The rpm jumped up and stayed between 4500 to 5500 for at least 10 seconds, I was coasting ain neutral. It came down and popped back up high again a few times. The idle eventually made it's way down to surging from apx 1000 to 3000. Luckily I was a block from my house. I do not have a code reader so I cleared the CEL by detaching the battery. The car ran fine until nearly 40 miles later today when the CEL came back on and the idle popped up and down from apx 1000 to 3000. Again I was lucky to be very close to my mom's. It sat for nearly 2 hours before I got a reader on it. The car had a CEL, but NO CODES!! and the Idle had returned to normal. I cleared to the code again by detaching battery and drove home about 20 miles, I was not more than 100ft from my front door when the idle became aggressively erratic again, but this time with NO CEL. WTH! The car bucks and jerks like crazy when this is happening.

THINGS I'VE CHECKED and DONE ALREADY:
brand new IACV 1 month ago
cleaned throttle body 3months ago
sprayed break clean to check for vacuum leaks
cleaned contacts on cap and rotor
plugged vaucuum and unplugged cruise control sensor
back probed TPS
NO EGR

please help, I do not know what to do. The car is completely stock except, I have replaced the motor with a JDM d15b, but it was born with a d16y8

SOHCgirl

Bump any help at all?

tony_2018

If the CEL is on than there is a code.

eghatch9295

iTrader: (1)

are you sure the obd-2 port is functional? jump the service connector in the passenger's footwell and see if the codes blink with the key on. if the cel is still on solid and not displaying any codes, your problem is most likely with the ecu itself.

SOHCgirl

I have not checked this but I will. Is it likely to go out just that sudden?

SOHCgirl

My cousin hooked up his super fancy reader and there were no codes.

SOHCgirl

I cannot check it, I forgot you cannot jump obd2

NotARaCist

iTrader: (1)

Uh, yes you can.

SOHCgirl

ok, well no need to be mean. I am not a pro. I will do some research and check this out.

NotARaCist

iTrader: (1)

...Mean?



The FAQ sticky exists specifically for people just like you. You really should read it.

https://honda-tech.com/honda-civic-d...tions-1998336/

Even more specifically, here's a nudge in the right direction.

https://honda-tech.com/honda-civic-d...lists-1901557/

eghatch9295

iTrader: (1)

....and boom goes the dynamite. jump that connector with scrap wire, a paper clip, whatever. if you have none of the above, cut the plug and connect the two wires together. if the cel still does not show a code, open up that ecu case and look for burn marks and/or leaking capacitors.

NotARaCist

iTrader: (1)

Oh gawd, don't cut the plug. If you don't have a paperclip, knock on the neighbor's door. Use a safety pin. Use a hair pin. Whatever. There's no need to cut the wires.

eghatch9295

iTrader: (1)

/\ lol, seen it done on way too many cars