In my book it lists a code 24# as :
Air charge temperature (ACT) sensor or Vane air temperature (VAT) sensor signal voltage is out of specification (engine off) or not at normal levels ( engine running)
or
Electronic Distributorless ignition system ( EDIS) fault failure in coil #1 primary circuit.
I can't help but wonder if you car doesn't have a ACT sensor on it and its screwing up. I remember you said you couldn't find one and today I'll dig out my old air box and take a pic and see if I can send it to ya. I have to also wonder if on the older models the VAT was like a MAF sensor for the N/A cars before it was used on a turbo. I don't mean it will look this same meaning it want have the vane part on it. I would disconnect the air sensor you got a replug it a few times to make sure its cleaned up a hair. I know its sounds like a long shot but you never know
As for the ECT code this may be a issue still. I know its probly hard to get to but try and get hold of the plug and move it up and down to try to get a better connection. Sometimes the connection get dirty or corrode and want make a good contact. I once had a GT Escort that had a problem of not starting after you drove it around a little bit. It seems that wants it was warmed up the ...crap I forget what its called...the sensor uses to add more fuel to warm the car up, once its warmed up its stops. Well on this car it wouldn't stop after warm up and would it would flood the car once you parked it. So like if you went to get a coke it would flood so when you came out to leave it wouldn't start. So maybe the ECT is faulty and causing it to run rich thus running like crap. I know all thats a long shot also but sometimes its the simple things that get ya, believe me