tatayee

I have a 99 civic ex with a b16 swap and a p28 ecu. it was idle surging pretty bad so I tried to scan it using an obd2 scanner but the ecu wasn't responding. am I using the wrong obd scanner? and what the hell is making it idle surge. I checked the iacv and the fitv. I also bled the coolant system. any ideas?

goldsy

Without knowing how everything is set up in your can I can't really help at this point. When you say the OBD2 computer won't respond do you mean it isn't showing you a code or it just isn't reading it period.

The P28 is an OBD1 ECU so for obvious reasons an OBD2 computer isn't going to do much for you.

Do you have a check engine light?

speedjunkie_g35

Vacuum leak. Obd2 scanner doesn't read obd1 ecu.

HondaPartsHero

Check the code using the FAQ in the 92-00 forum if the check engine light is on.

tatayee

ok well that solves that problem I was using the wrong scan tool. no it isn't throwing a code which is why I am struggling to find the cause. when I first start it in the morning it doesn't like to stay running unless I keep on the gas until it gets some what warm. it runs fine afterwards.its been cold out lately though. it has crower cams in it. could it just need to be tuned again?

goldsy

Any trouble starting it when it's cold or just hard to keep running?

tatayee

it normally takes just a second for it to start nothing too abnormal I suppose. but then itll die if I don't keep the rpms up until it gets warm. but if I let it die then after that its hard to start I have to pump the gas to get it to turn over. it only does this when its real cold outside. I don't have this issue mid day or so.

motoxxxman

yeah you just need to get it re-tuned. I wouldn't be surprised if it isn't even tuned at all right now. or it's tuned really poorly. a full tune does not just make it run properly when at operating temp, a full tune includes tweaking all the different compensations so it starts normally in any weather, and runs properly at all temps. if there is no cel, there probably isn't a mechanical problem somewhere, especially if you say it runs pretty good when warm.
and besides, when a tuner begins his work, he'll be able to diagnose the issue for you to be sure