This one has been driving me and my friend nuts for a month now....I'm sorry this is long winded, but it's a very bizarre problem.
95 Civic LX, 190000km. 1.5L
This problem has gotten progressively worse over the course of a few months, and is now to the point where the car is not drivable....
When the car is running, if you push on the gas fairly quickly, the engine will die so quickly that it seems as though ignition is being cut. If you accelerate the motor slowly and smoothly, it runs fine with no ignition misfires, roughness, etc. Also, if driving, the engine will quit when under any heavy load, such as starting from a stop in first gear.
When the engine/ignition quits, if you lift on the throttle right away (before the engine stops turning), it will come back to life! Here's what I have done/checked so far....

-There are no codes registering in the computer.
-My first thought was fuel pressure or filter. Both of these things have been checked and the filter replaced.
-Then I thought that it was vacuum related, because when you open the throttle quickly, vacuum suddenly drops. I tested the MAP sensor with a scope and it APPEARS to be working fine, although I'm still not convinced that this isn't the problem....see below.
-I assume that the TPS is working okay too because the car will run fine if you open the throttle slowly. This was also tested on a scope and it looks okay.
-We also tested the injector harness and all injectors are getting pulses right up until the engine comes to a stop.
-The CPS sensor in the distributor had weak numbers, so that was replaced, but it did not solve the problem.
-I have replaced the ignitor, no change.
-I have replaced the coil, no change.
-I have NOT tried a new MAP sensor because they are expensive and the scope said it was okay, BUT I still suspect it due to the relationship between the problem appearing when vacuum drops....
- I cannot see/hear any vacuum leaks, and the car idles fine.
- There is no blockage in the air intake, filter is clean.
- I have NOT replaced the cap, rotor, wires or plugs at this time because that just seems too much of a long shot and I don't want to introduce any more variable. Like I said, the car runs fine if the accelerator is applied slowly, and there is little or no load on the engine....

If anyone has ANY ideas, no matter how bizarre, please let me know. I'm going crazy!


[Modified by kholly, 3:05 AM 6/25/2002]

 

did you ever figure this out.........i'm having the same problem.......or can anyone figure this out......mine doesn't completely kill the motor but it missfires pretty bad

 

sounds like a weak fuel pump to me

 

thanks i'll keep that in mind when i fix it tomorrow