sr red top problem

[ford_o]

hello i have 89 240sx with a red top sr, my car has been running fine for the last couple of weeks or so, but yesterday i swap my mines ecu for the stock ecu and when i drove it,from the start it had a bad start and bad idle like its missing bought it home checked the spark plugs and they were all fine except the number 2 plug it had gas on it like it was fouled out or something. swap that one out and started it up and the same problem so i left the car running and unplug the coilpacks one by one and the all made a diff. except the number 2 coilpack. i kno that is my problem but i dont understand how that problem occured by swapping ecu. any help would be nice and if you need more info i'll be glad to share it thanks ford!!

[jiggs]

Probably the mines ecu was pre set for a certain setup, now the stock ecu doesnt know what to do when it reads after market stuff

[ford_o]

the mines was a stock tuned ecu nothing is really aftermarkert

[j87w]

Check to make sure your getting spark and fuel to your #2 cylinder and troubleshoot from there.

[ford_o]

im getting fuel because the spark plug is covered in it when i pull it out from the #2 cylinder

[RBPowerSilvia]

i know what your trying to ask but i dont know why that would happen just from swapping a ecu.... but this what i would do, get the ohm specs for the coil packs, test the coil pack by seeing how much resistance it has (ohms)... it may just be that you have one bad coil pack.. but make sure you change that spark plug again when you throw a new coil pack in it because that plug is already fowled.. let me know how this works out.. -Adam

[wings_s13]

well if it is just a tuned ecu then u could be asking more out of your injectors so u might have a bad number 2 and its just dumping gas in there might be that other then that start at the plug and pack and work your way from there. good luck man

[ford_o]

just tested the coilpacks they all seem to work how i tested was i took the one that wasnt working and put it in a working slot and still the same problem so its not the coilpacks.

[j87w]

Get a meter and check the resistance in each coil pack. IIRC it should be around 1 ohm. From what you say I doubt its a coilpack problem though. You may have a stuck injector. Have you tried swapping your injectors around from say 2 to 4 and 4 to 2? I would try that. If that doesnt do anything I would go ahead and do a compression test.

[ford_o]

me and my just did a compression test on all the car and they hit around 140ish except the #2 and it was 130ish so that might be ok idk. im gonna try the injecter thing tomorrow. in doing more test i figured out the cylinder is getting a lil spark cuz if i let the car run and pull off the coilpack you can hear some popping from the sparkplug so it could be getting spark or maybe just not enough. if i leave the coilpack in the car and unplug it nothing happens but its getting spark so i just dont understand. but imma try the injecter thing and see if i can figure something out. i also drove the car tonight and it had a rough start and very bad idle drove around ok not great alot of backfire,but it still hits boost like theres no problem at all but in vac it starts again its weird and hard to explain im doing the best i can tho!!!

[ford_o]

just pulled the #1 and #2 injecters to swap them over and i found that the #2 injecter o ring was broke got a new and switched the injecters and runs great again thanks everybody who helped