2G misfire in cylinders 1 and 3

[zcoh2gdsm]

not sure whats wrong, only started happening when i put the car back to stock. i replaced all the plugs and gapped them to .28 however it made no difference, i know its cylinders 1 and 3 cause when i pulled the plug wires it made no difference. i didn't see any arcing in the wires, any idea why it would randomly start doing this after i put it back to stock?

 

[92AWDHX40]

Could be a coil pack is acting up, or injectors not firing.

 

[mchustle]

I would say coil or power transistor. Since you were messing around under the hood make sure your power transistor is plugged all the way in.

 

[zcoh2gdsm]

I would say coil or power transistor. Since you were messing around under the hood make sure your power transistor is plugged all the way in.

i was just thinking the power transistor also, it would make sense because it's only those two not firing. i didn't touch the power transistor but i could understand if it needs replaced, the cars 15 years old so far everything else needed replaced.

Could be a coil pack is acting up, or injectors not firing.

all injectors are firing, its spark, making me think its the power transistor.

 

[92AWDHX40]

Im thinking more the coil pack, test it out.

 

[zcoh2gdsm]

Im thinking more the coil pack, test it out.

if it were the coil pack wouldn't all cylinders have no spark?

 

[steve]

Since it's 1 and 4 paired, 2 and 3 paired for the ignition, if you really are having a problem with 1 and 3 you need to look much deeper into the whole setup or much closer at the parts you just changed.

 

[zcoh2gdsm]

Just tried a new ECU and the misfire changed from 1 and 3 to 2 and 4. I'm stumped. I haven't done a BLT yet because I don't have a compressor right now but that's next on my list. I did see smoke coming from the front O2 sensor area also, I didn't see a crack but it was smoking from that spot.

steve, only parts I changed was putting the stock airbox back on, taking out the EPROM ECU and putting in the stock one, then taking out the wideband and boost gauge.

 

[casperfast]

this is an all too familiar issue. check the pack to see if he inside looks burnt.