This is a obd1 B18B1 in a 94 sedan, manual. It is running the stock ls ecu. Two weeks ago, it was running beautifully. Then it started to stutter on the highway, only for about 30 seconds. No CEL. The sputtering was random. Then it started to do it even while driving around town randomly (90% normal, 10% ****). It is so bad that in town, I would say it "bucks" as it goes from bogging down to running normal to bogging down again. No matter how much throttle I give it unless it's WOT, then it doesn't buck, but you can tell it isn't running right.

No CEL. I've changed:

TPS
Injectors
Fuel Filter
Cleaned the IACV
Distributor rotor (cap looked new)


The only things left are the MAP sensor and the entire distributor! oh and the little sensor thing underneath the throttle body.

Anybody have ideas before all my hair turns gray??

It definitely feels like no gas. I'll press the gas down and you can hear the difference in sound, but it doesn't go... kinda like when you try to rev a carbureted motorcycle before it's warmed up and it runs, but it just sputters. Or is that too much gas?? I don't know. This is really making me mad though!!!!!! Any help would be extremely helpful!

 

my plug wires caused my si to do that.

 

any other ideas? The wires and plugs are new, sorry i didn't mention that.

 

Probably won't like hearing this but I had a B17 92 GSR that did the exact same thing. Changed all the above just like you have. Ended up being the dizzy anyhow. Try swapping a buddies in

 

ok, just changed the distributor with a reman. In order for the car to run halfway decent, the distributor has to be turned all the way counter clockwise. And it still doesn't pull like it should until I get above 3k. It's not running as smoothly as before either. Could the thing have jumped time?

I didn't look at the timing belt because you have to take the valve cover off and I didn't want to mess with the gasket unless I had to.

It only did the jerky thing once and that was with the distributor turned a little bit clockwise.

Weird!!!!!!!!!!!!

Any ideas???

 

spoke too soon. same symptoms.just took a few miles to show up. maybe its just psychological, but the symptoms seemed less severe. i put the original back on, i'll know tomorrow if the symptoms are identical or not. its making me mad!

could some wire be rubbing somewhere worn off the insulation causing intermittent shorts?

 

But still fine WOT? or it bucks at WOT too? It wouldn't hurt to check timing since its free.

 

what plugs did you use?

 

I had that problem in my 91 integra it was the coil pack in the top of the distributor I know u change yours but it my be worth taking a look at

 

How much gas do you have? If you're super low, it may just be low on gas...

 

Had ngk in it, replaced with denso pk16tt, same problem.

 

Well it'll Buck unless its held at certain positions, wide open and 3/4 seems to be the best.

 

It was a remanded, so who knows????

 

Full gase

 

Felt like a clogged cat so I put on a greddy exhaust with test pipe, same deal. Replaced map, same deal. Replaced the p75 with a p06, same deal. Got a known good iacv, will put it on tomorrow ..

My cousin said the ground might need cleaned up, what say you guys?

And what's the name of the sensor under the throttle body? I hear it can go bad

 

that's your Fast Idle Thermal Valve. clean that bish up good. it'll help. i'd check your timing belt. very possible it could be the problem.

 

iacv's in, no change. Could it be the fuel pump? Before all the problems, we had run it down all the way to the point it cut out and wouldn't stay running.

 

check your FITV (my previous post). Fuel pump could do it too.

 

go to a cheap tool store, harbor freight maybe? buy a cheap fuel pressure kit, hook it up and see if it reads around 45psi. If not, the pump might be you problem.

 

Since you have had the dizzy off I think its in your best interest to take a timing light to it. I've seen where the dizzy was clocked just a little off and it ran like *****, however this was not a stock dizzy. On a oem dizzy I have seen it clocked to the right orientation and it made the car run so much better and smoother.

 

hey i know when my car did i had to get on it for it to clear up then after a few weeks or so it did it all the time no matter what ended up being valve...check them as your last resort i guess

 

When was the last time you changed the fuel filter? How does the fuel pressure look?