for a split second, car fails to accelerate from a stop, runs rich.

[lucid]

My otherwise perfectly functioning H22 Accord has started to give me signs of needing some attention soon. I think I have a sensor problem.
I noticed the first sign less than a month ago. Where there was none before, I now have a lot of carbon coming out of the tailpipe, and it's making the right side of my car noticeably dark from it since I haven't bathed her in a while.
I'm running rich, so I naturally suspect the O2 Sensor...It probably has 180-220k on it.

Then within the past week, the car (engine) doesn't accelerate from a stop when I try to go. I'll give it a little gas and let out on the clutch like normal, but it's like the car doesn't know I'm hitting the throttle. It will feel like there is no power, for less than a second, then instantly the power kicks in and the car accelerates normally.

I am expecting a sensor problem, but am wondering if the 02 sensor alone can cause both symptoms, or if it could be the TPS or MAP sensors too/instead.

I do not have an EGR, EVAP, or FITV system. The car is a 5-speed.
The Igniter chip, cap, rotor, plugs and wires are all new, (~20k).
The O2, MAP and TPS sensors, coil, dizzy itself, and alternator are all old and suspect.

I have a small stereo system that probably doesn't pull much more than about 10 amps (~130W), but I'm using an unknown-mileage junkyard alternator from an F22 at the moment.


I am away from home right now in NC, so I don't have any spare parts to swap with, but I do have most of my tools, including a multimeter.
I have spares of whatever part I need at home, from my other engines, except another dizzy.

For now I am going to clean up the ignition system (plugs/cap/rotor) just to be sure that stuff's good, but since the engine power is instant off-to-on I still suspect a sensor.

I do have my Factory Service and Haynes manuals here, and could check /adjust my TPS, but I set that perfectly when I built the motor. My idle is still fine, so it could be going bad, but I doubt it moved.
I may have a tiny vacuum leak on top of my S2 throttle body where I have just had tape covering the bolt-on MAP sensor hole (since ours are in the box on the firewall), I will fix that when I clean the ign. parts.

I probably wouldn't make a thread for this if I were home, I'd be in the garage playing swap-the-part.
But since I can't do that where I am now, I may as well ask for some brainstorming help. Any knowledgeable advice or suggestions are welcome. Maybe one of us is familiar with these symptoms. I'm sure whatever is happening to my car has happened to someone elses.

[cb9wagon]

by chance do you have an internal coil?
if so i recommend go to exernal. i had some pretty ghost type issues that would come and go, conciquently the coil upgrade made it go away.

[cb9wagon]

forgot to ask
how is battey voltage under load? (lights,stero,blower fan)

[lucid]

by chance do you have an internal coil?
if so i recommend go to exernal. i had some pretty ghost type issues that would come and go, conciquently the coil upgrade made it go away.

No, I stayed external coil so I could upgrade to MSD parts later. Coils usually go bad all at once tho.

forgot to ask
how is battey voltage under load? (lights,stero,blower fan)

Power to everything seems fine, no problem running many accessories at once at idle.

It does not do it every time, but still occurs frequently enough to notice while stop-and-go driving.

[cb9wagon]

does your mil (cel) come on? what codes?


how is the egr valve deleted?

what if it's going into limp mode because it coding . you said this is a new issue so it's unlikely. even so it worth a look. try to backprobe your o2 sensor with your scanner

[Losiracer2]

I was having this issue too when I did my swap a week ago. It turned out my grounds were faulty. check ALL of them and sand/clean the mating surfaces of all of them. You might even want to add more grounds just to make sure.

[lucid]

does your mil (cel) come on? what codes?


how is the egr valve deleted?

what if it's going into limp mode because it coding . you said this is a new issue so it's unlikely. even so it worth a look. try to backprobe your o2 sensor with your scanner

No, it's not throwing a code...yet. It's a new symptom that's barely noticeable at this point. Chipped P28 ECU.
EGR Block Plate, solid gasket, valve removed, P28 doesn't look for it.

I am OBD1, not throwing codes. I don't really have a "scanner", can I use the multitester to check the O2 sensor? I'll be replacing it with the ~30k mi. sensor I bought for the 'lude when I get home.

I was having this issue too when I did my swap a week ago. It turned out my grounds were faulty. check ALL of them and sand/clean the mating surfaces of all of them. You might even want to add more grounds just to make sure.

A few months ago I redid all the grounds and made an 8ga. ground kit tying all the stock grounds together and switched my battery posts to gold-plated block terminals. And the battery's new. If it's in the power system I would suspect the alternator since it's the only old thing left....or a loose connection.
I will check to make sure all my leads to the battery terminals are still good and tight. And check voltage with everything running to test the Alt.

Thanks for chiming in, guys...I still need to give the ign parts a little cleaning too, I'm going to feel pretty silly if I can build an engine but not clean plugs, haha.
So I'm guessing that bucking isn't coming from the O2 sensor and I'm looking at two separate issues. I've had bad O2 sensors and driven without one while running open header and not had that stutter.
Hopefully it won't be raining tomorrow and I can make some progress.

[cb9wagon]

the o2 sensor wouln't be a bad investment
hope it helps or at least helps find the problem

[cb9wagon]

[QUOTE=
I am OBD1, not throwing codes. I don't really have a "scanner", can I use the multitester to check the O2 sensor?
QUOTE]

yeah, i belive the signal wire is the blue one and set volts. you will get .100 for a low and .900 or so for a high. there are no exact numbers but it should bounce up and down.

this is kinda crude but at least you can see if it's stuck high or low

[lucid]

update

I checked and tightened the battery clamps and wires-
cleaned the plugs, cap and rotor-
resealed the MAP sensor hole on the throttle body-
tightened the alternator belt-
found an screw rolling around under the cap and reinstalled it to the dizzy- holding the assembly the igniter mounts to. everything still looked okay.

Test drove it for maybe 3 miles thru town.

Tune up didn't help the bogging issue, I went to go at a green light, pushed the gas down and the car had nothing, the engine was making a low fluttery sound 'til after 2000rpm when it picked up. I think it may be getting worse.

[cb9wagon]

any chance the ignitor overheated not being attached firmley to aluminum dist housing?

i can't really remember if they are supposed to have dielectric grease to help disipate the heat into the body

[lucid]

any chance the ignitor overheated not being attached firmley to aluminum dist housing?

i can't really remember if they are supposed to have dielectric grease to help disipate the heat into the body

Doubtful, the igniter assembly screws to another cast piece, the screw that came loose holds that cast piece to the main distributor body.

I wouldn't expect a heat or grounding issue from this. Worst case scenario the screw itself could have gotten down into the geared portion of the dizzy or shorted a connection at a sensor or igniter terminal. The heat/dust shield inside the dizzy has been removed, by the way.

At this point, I don't have a good reason to think the problem is in the dizzy.
I look at that as just being lucky and catching something else before it went wrong. Everything was still tight, the screw was on the bottom and nothing looked damaged.

I wish I had my parts here, I'm running out of things I can do while away from home and hoping things don't get worse before my 330 mile drive back.

[willhholla1]

i hav a similar problem, hav u checked for a vacuum leak or exhaust

[lucid]

I went lightly over the vac lines, moving them around while idling, nothing too in depth- all looked well.
My idle is still low and even, and I just ran all the lines about 10k mi. ago when I put this motor in.

I dis- and re-connected the tps and IACV connectors just to make sure they are making good contact with the sensors.

I may try to test the tps with my multimeter for range and throttle response.



It's got to be something electrical, doesn't it?

It's like the timing or the AFRs are totally wrong in the bottom end, or the spark is weak. I can resistance test the coil I guess, but I thought those crap all at once.
I would imagine that: If the TPS is failing to respond to the throttle's first movement, the ECU wouldn't know to give more gas at the injectors to match the increase in air flow, or to adjust the timing to accelerate.
Which could create the bogging symptom in the bottom end maybe?

I wish I knew.
Eventually I will.

[lucid]

Update:

Ok. I've been back home since mid-January now, but been lazy about addressing this problem.

The "miss" I guess it is has been slowly getting worse.
The car chokes briefly under mid and heavy throttle usually below 2,000 RPM.
I did a bit of stop and go city driving for a couple days and it was pretty bad, happening at about every other stoplight when I try to go.
A few times it was not just a little miss, I'd mash the gas and it would struggle to go for a full second or more, with a little pulsing feel to it.

I replaced the very old O2 sensor today and it did not change the symptoms.
I didn't really think it would fix it but it should help my AFR anyway.

Now that the miss is worse I find it familiar..
I think it is my 200k+mi distributor, even tho my igniter chip is fairly new.
I don't know if it's just a break in the wiring, or one of the other sensors in the dizzy, but I am planning on buying a new dizzy when I can afford or it craps on me completely.

I have had distributors cut out on me so bad the car would jerk back and forth, or cut off and drift.
Since this seems to only happen at lower RPM, I don't know if it's just that I don't notice it at higher engine speeds, or if it could be from the alternator not making enough juice for the ignition system until higher rpm.

Really those are the only electrical accessories still old on my motor.
I have not checked or swapped the TPS or MAP sensors yet.