MadMax

I have a B16-a in a '91 CRX that has run flawlessly since I shoehorned it in two and a half years ago, well up until about 2 weeks ago. Then it started leaning out when I'd let out of the gas for any length of time. This progressed to leaning out when running with a consistent throttle postition; ie. level ground. Now it leans out and dies or tries to any time the throttle is opened.

Here's what I've done so far:

I installed a new fuel pump, fuel filter and changed the fuel regulator valve. I've also taken off the TB and inspected it and all the vacum lines.

The last mod I've made to the car was about 8 months ago I replaced the alternator and while it was down, I added a MSD ignition, coil and dist. cap. After these mods were made, the idiot light for voltage has been on but the battery has stayed charged.

Could this be a ECU problem or have I missed something else? Any help would be greatly appreciated.

Thanks in advance!

malfuncion

i know when you add msd stuff you tend to lean out. i have seen this occur on both my car and on another civic that had an msd setup. you could try an aftermarket fuel pressure regulator. yours might of just slowly blown out. all thats in there is a small diaphram controlled by vaccum....umm thats my .02

MadMax

Thanks for the input.

I already changed out the regulator, there's plenty of fuel pressure I'm sure. I loosten bolts to change or check stuff and fuel sprays out under pressure.

I have a air/fuel mixture guage and after I installed the MSD stuff it did lean out minimally. This problem has JUST started after 8 trouble free months. I'm so afraid it's the ECU. Is it possible that it could start flaking out and gradually get worse like my problem?

(I'm sure I'm not as clear on my problem description as I should be, sorry for you having to descipher my mess)

malfuncion

k, well alot of questions....when did the voltage light come on? was it when you let out on the gas while driving or was it constantly on? did you replace your regulator with a stock or aftermarket adjustable? do you have a fuel pressure gauge? have you looked under the distributor cap to check to see if all those contacts are hooked up still? as for the ecu im not too sure if it can slowly flake out, ive seen them just die...i guess there were some events kinda leading up to it just dieing, made us think it was the fuel pump ect ect...turned out the ecu just fried. it was in a 240 with crazy electrical problems...guy who previously had it used gum wrappers as fuses...

MadMax

Voltage light came on as soon as I turned the key after the alternator / MSD upgrades. I replaced the regulator with a stock one. I didn't want to spend the big bucks on an aftermarked if that wasn't the problem, I'll buy that later when I'm not spending a ton to try to get the fool thing running. No fuel pressure guage - yet. And no, I haven't looked under the distributor cap. Would connections under there somehow connect to something that changes pulse width of the injector spray?

Watching the air/fuel meter is what has led me to believe there's some fuel shortage to the engine. Open throttle = the guage going into the red and disappearing. Car detonates and won't rev. Massive lean condition. It's as if the injectors are remaining constant with what they're sending to the cylinders, pushing only the idle speed amount per cycle.

By the way, this is a first gen B16 if that matters, forgot to add that in the first post.

malfuncion

ok well for the dist cap it could be that the coil you added, you know how you have to splice in, that could be shorting out. thats off the subject of fuel and it really wouldnt have anythign to do with you leaning out and detonating...if you are electronically inclined a lil you could open the top of your ecu and look around on the circuit board for any blown leads or traces...also check for bubbled resistors...but im kinda highly doubting its your ecu. ok as for the injectors there is a unit that works with them its called the injector resistor box. it is a small gray unit with cooling fins on top. on my 89 hf, if you were looking at the engine it would be to you rright side, up as close to the firewall as possible. i think its right next to the hood hinge...but that may have went out. here is a post with a pic of it
https://www.honda-acura.net/forums/s...A+resistor+box


i pm'd a guy about this and he might post something to kinda help us out..

MadMax

Any word from the guy?

sorry for the impatience, I just wanna drive my car again =)

malfuncion

not yet i pm'd him and no reply yet

MadMax

Alright, after taking a bunch of stuff apart to check and the battery being disconnected for about 4 days, I put it all back together and immediately it ran perfectly... for about a mile down the road. Then it went back to going lean, then running good, running lean, stopping and patting the throttle for a few seconds then it running well again.. so forth so on..

Any clues?

malfuncion

if you can try to get ahold of another ecu..i really dunno anything else without seeing it..