QwkSC

iTrader: (1)

My 1992 SC400.

Recently replaced the cap, rotor, plugs, wires

Symptoms:
-really rough operation between idle & 2000k rpm
-feels a little sluggish throughout the powerband
-smells a little rich out the tailpipes

I unplugged one of the coil packs and the car refuses to start
unplugged the other and it starts but runs rough


I think spark is the problem, but any suggestions on what specifically it could be?

RedPhoenix

iTrader: (10)

Unplug the maf... keep the car alive at idle, but drive with it unplugged... Does the car seem faster?

OMD

since you said that when you unplugged one of the coil packs and the car refuses to start then unplugged the other and it starts but runs rough then this means that the second coil you unplugged is kaputt(broken).. i say replace both with new ones since i think it is also time for that maintenance part to be replaced..

QwkSC

iTrader: (1)

No change with MAF unplugged

QwkSC

iTrader: (1)

Replaced Coils, no change in operation

Just retrieved codes
14
Ignition Signal
&
24
IAT Sensor Signal

any Ideas?

Ive checked everything that has to do with spark and unplugged the MAF and still nothing has worked

over40driv

I feel you pain buying two new coils and not solving the prob. The computer has to fire the coils at some point in the game. You might price one through algia and give that a shot. Maybe someone with a spare like you will have, if it dosent fix your prob. would loan you one.

SHOLEXMAN

Interesting with the coil issue. Does it still not want to start with the new coil unplugged? The code for the the Intake Air Temperature might indicate you have a faulty MAF. Usually when the MAF is unplugged the car should die if you put it into drive. Just wondering(it happens) Did you by chance get the wires mixed uo when putting then in? Is the wires on the spark plugs fully or are they touching them? Spray some intake cleaner inside the MAF cause there is dirt that gets on the element and can mess it up sometimes giving the ECU faulty readings. Check the other stuff mentioned and get back to me.

QwkSC

iTrader: (1)

I did a tuneup a month ago and It ran great untill this week. Recently it's had more and more tries to keep it started. But that sometimes happens, sometimes doesn't so I believe that is a seperate issue

couldn't both codes have been caused by unplugging the coil and MAF?

over40driv

Good idea about the codes being set by unplugging the sensors. I think we also have two coil ignitors that sit on top of each other on the drivers fender well. I would think the comp. tells them to fire. My son had a 92 Nissan Maxima that had the same symtomn as yours and it was the comp.

SHOLEXMAN

That would be my next thing to mention. A person similar to QWKSC has the same issues sometimes it doesn't want to start at all and then other times it fires right up. In this case though the ECU has codes. The code would come up if it was unplugged and you started it so many times then it would come up. The light would go off if you got it working again though. Try and find a used MAF or a extra ECU to borrow and see if the issue persists. There also be a possible issue with your ignitor going bad. I am looking at the MAF first though that could cause both issues cause the MAF controls the ECU when to fire and send out fuel and at what time. Clean the MAF and clear the codes and run the car and see if the light comes back on. If the light does come on change out the sensor or borrow one.

QwkSC

iTrader: (1)

I think a trip to Pick&Pull is in order. I'll try both the MAF and ECU