Ignition dropping spark??

adamkaul · Feb 1st, 2004, 06:49 PM

1987 nissan stanza gze. ca20e motor. New distributor, cap, rotor, spark plug wires, spark plugs. Computer not shooting codes. Coils appears to be in good condition. The Problem appears to be that the ignition is dropping spark. The RPM Seems to vary between 3000 and 4200, all depends on how far down the gas pedal is. The further down, the lower the rpm. The motor runs great, until it drops spark. Timimg is set at 15 degrees as the tag under the hood says it should be. My question is, why would it drop spark, what would cause that, and how to remedy the problem.

KA24Tech · Feb 4th, 2004, 06:15 PM

Does it have enough fuel? Try replacing the fuel filter and checking the fuel pressure. I have seen on more than one occassion where a clogged fuel filter was causing this exact problem.
If that is good then we might go troubleshooting your ignition.

Troy

adamkaul · Feb 4th, 2004, 11:51 PM

Matter of fact, the fuel filter was the very first thing I changed....It was the cheapest...

) The previous owner replaces the plugs, all in all about 6 months ago...what are the chances that 3 of the 4 intake side plugs are fouled? The number 3 plug fires all the time, however 1,2,4 dont spark at all...ever..and spark on 1,2,3,4 on the exhaust side is dropped at 4000rpm. This is definately a wierd problem...mind blowing....gives me a headache.

KA24Tech · Feb 5th, 2004, 12:56 AM

Try testing the pickup trigger and coils. Do you have the Haynes or Chiltons manual for the Stanza? If not I can get the test measurements for it.

Troy

adamkaul · Feb 5th, 2004, 01:09 AM

I flipped the intake and exhaust side coils to see if the same spark problem happened but on the opposite sides, and they didn't(as far as only one spark plug firing goes) Didn't test the pickup trigger; not exactly sure what that is. Is that the electrical unit in the distributor or the electrical unit mounted next to the coils? I do have the haynes manual, however, that manual is about as general as could be. If the pickup trigger is the unit inside the distributor, i just replaced it with another used one with the same problem happening. The old distributor was leaking oil anyways so it needed to go. What is that electrical piece mounted alongside the coils? My E-mail is adamkaul@softhome.net if you would send the test measurements, that would be greatly appreciated.

KA24Tech · Feb 13th, 2004, 01:43 PM

Quote:

Originally Posted by adamkaul

I flipped the intake and exhaust side coils to see if the same spark problem happened but on the opposite sides, and they didn't(as far as only one spark plug firing goes) Didn't test the pickup trigger; not exactly sure what that is. Is that the electrical unit in the distributor or the electrical unit mounted next to the coils? I do have the haynes manual, however, that manual is about as general as could be. If the pickup trigger is the unit inside the distributor, i just replaced it with another used one with the same problem happening. The old distributor was leaking oil anyways so it needed to go. What is that electrical piece mounted alongside the coils? My E-mail is adamkaul@softhome.net if you would send the test measurements, that would be greatly appreciated.

I have send you a couple of PMs so let me know.

Troy

adamkaul · Feb 26th, 2004, 12:31 AM

Quote:

Originally Posted by KA24Tech

I have send you a couple of PMs so let me know.

Troy

Took it to the mechanic, however he did not know so much about the motor. He believed it was the computer, because he thinks the computer is what switches the ignition from 8 to 4. How does the motor know when it is under load? is there some type of vacuum operated ported switch or something that switches when the vacuum in the motor changes? When you mash the pedal to the floor, vacuum drops, right? Whatever tells the computer that it is under load, i could just disconnect it so that it doesn't try to switch.