justinmaccc

Okay so I just got tags for my b16a2 swapped 98 ex. Last night I was out running around driving it and at the time it was only throwing a code for the second O2 sensor (not wired in)
I noticed as I was driving it seemed very hesitant up until 3k and as soon as it hit 3k you could feel a noticeable increase in power the engine runs very good anywhere over 3000 rpm.
(I think this problem is not related to the next one)
Anyway I'm driving around and at every red light or stop sign it seemed very sluggish off the line, almost like the rpms dropped way low and it just sounded like it was going to sputter out and die. But regardless I kept driving and I noticed a few times when I let off the gas with the vehicle still in gear and coasted, when I put my foot back on to accelerate it wouldn't go anywhere and then all at once the it would go. Jerking the car a bit. Immediately I knew something was wrong. So I decided to head home and as I stopped at a stop sign on the way home the the rpm dropped to zero and the car died. It wouldn't start after this and with every crank the electronics in the car would turn off. This makes me think dead battery or alternator. But after waiting about 10 minutes and checking for loose connections in the engine bay the car started and shut right back off. I figured out that when I could get it to start I needed to keep my foot on the gas so the rpm didn't drop and kill the engine. You can imagine how frustrating it is when you have to go around a turn and you let your foot off the gas and the car dies instantly.. I made it home luckily and when I got there I had a few codes 1.) idle air control valve
2.) fuel trim malfunction (I heard this one could be a vacuum leak)
3.) knock sensor (the sensor was partially unscrewed from he engine)

I reset the codes and started te engine, it idled for a few minutes and when it got up to temp it died.. But now it's only throwing the O2 sensor code again. I should also add that the Evap canister is not hooked up because there is no plug for the purge solenoid on the d16y8 harness that I'm using.

I find it weird though how I was driving around fine one second(besides some bogging) then the next I'm stranded and the car won't keep the rpm above at idle speed.

When I get off work tonight I plan on cleaning the iacv, checking for vacuum leaks. Fuel pressure is good. And Testing the tps any other suggestions? Would really like to get my freshly swapped b16 running correctly so I can drive it lmao

delsolintegra

Could be a couple of things.

Engine coolant temp sensor could be bad. The ECU thinks the engine is always cold and dumps too much fuel to start a warm engine. Fuel air ratios and timing will be off and you will have bogging at low rpm. A cold engine will start like normal and run like normal until it warms up to operating temperature. Than the ECU goes closed loop and the problems would start.
Check the spark plugs, if they appear wet the ECU could be dumping too much fuel. If they are light gray in color instead of tannish white they could be burning too rich of a mixture.

I would also check the MAP sensor rubber O ring gasket. A vacuum leak there would cause engine bogging under load.

justinmaccc

Thanks for the quick reply! I get off work in 3 and a half hours Ill tear into it then! Really wish I had a scanner with live data. Would make things so much easier lol. I also forgot to add that I just recently put in new plugs, distributor cap and rotor and an icm but I didn't drive the car much before that so I don't know if this is a result of somethig dizzy related or not

justinmaccc

Okay so I just did some research and I know that the two sensors on the end of the head by the distributor are definitely plugged in, as for the one on the back of the block(the one that has a nipple on it) there is no plug on the d16y8 harness for that one. I actually didn't know what it was until just now. Could that be the source of the problem? 2 out of 3 sensors are there. I don't know how crucial the one on the back of the block is. After all the engine was running and driving without it before.

justinmaccc

Raining hard here in baltimore, won't be able to get any work done until tomorrow. the car is sitting in 2 inches of water lol. Ill keep this thread updated when i can get out there to start testing stuff. any further input on the subject is much appreciated!

justinmaccc

Okay so today i cleaned the Iacv with brake cleaner, map sensor oring looked brand new. fps voltage was good. i opened the distributor and one of the connections on the icm was falling off.. i guess when the car died and then abruptly stopped it knocked the connector off and it wouldn't start and when it did wouldn't hold an idle. so at least that was an easy fix. Problems like this seem impossible to diagnose you have to just start replacing sh*t to find it lol. i crimped the connector so it fits much more snug. won't be falling off again.

As for the bogging and hesitation, those problems still exist. Im thinking a vacuum leak but I'm not entirely sure. I'm hoping someone here can give me a starting point as to what could be causing this. going to a do a bit of research for myself as well. any help is appreciated!

bigtimegambler

I have the exact same bogging problem up to 3000 rpm. However I only have the problem after hitting vtec. If i don't hit vtec it runs fine. Are you running in vtec every time you drive your car? I also think it could be an o2 sensor thing. I know I'm not running an o2 sensor (deleted with my tune) and that could be a cause. Definitely check for vacuum leaks. Is your timing okay?