I have a 87 N/A coupe that ran well with the original auto trans. I swapped out the auto for a 5sp, now it won't idle, just dies, runs like crap under 3k and under a load has a rattling sound that comes from the passenger side of the engine, towards the firewall. Follows the symptoms of detonation. Ive adjusted ignition timing at the CAS out and in, also added two bottles of octane booster. No effect. I've tried two N326 ECUs both ran the car the same. I have eliminated the cats in the swap as they had some leaks anyway. I can't see or hear any vacuum leaks, but not ruling it out. I know there can be any.number of things wrong, so any suggestions are appreciated. Any more info needed, please ask. Thanks!

 

It may sound stupid,but check the path of the spark plug wires and make sure that L1 and L2 go to the bottom plugs.(Best is L1 to lower front spark plug and L2 to lower rear spark plug..BUT if you mix them up it is OK as they fire at the SAME time!)
Then check and make sure that T1 goes to Front top plug on front rotor and T2 goes to rear Top plug on rear rotor.This is crucial that you get this right.
I've encountered guys mixing up trailing wires and it sounds like detonation.

 

Misterstyx69, sir..... You are a genious! I had them crossed t1 and t2 crossed and l1 with l2 crossed. Corrected them, and now shell idle, no detonation sounds, and starts easy. Still has a flare to the idle though. Like it pitches up and down around 1100-1600rpm. Any ideas? Thanks again Styx, you are awesome!

 

W/the car as warm as it can get measure the Green/Red wire of the TPS and set it to 1 volt w/key to on.