I have a saab 93 2002 with engine codes,p1110,p1312 and p1334 showing can anyone please tell me what they mean!

Fault location, ignition coil---knock detection, cylinder 1&2 probable cause, wiring open circuit/short to positive, ignition coil assembly, ECM

If this is a SAAB the DI cassette needs replacement. Easy fix but the part is high. Use only OEM part as the cheap stuff does not work. Plugs are under this unit so good time to replace them also.

The codes are on the internet

Type: OBD PO201

2003 Saab OBD P1312

OBD PO 245

I see no one else has posted an answer for you here yet so I will take a stab at it for you. The P1300 codes I am familiar with on the Saab's are P1334 and P1312 which almost always means the ignition cassette is failing. Most of the time the car will still run good, at least at first anyway getting worse over time. They are not cheap, ebay has the lowest prices and most availability that I know of. They are very easy to replace, just one electrical connector and four large torx screws right on top of the engine. If you have a black one replace it with black, red with red. To be absolutely sure you get the right one it's best to match part numbers. That being said most of the ones I have used have been interchangeable as long as they are the same color & # of cylinders.

p0420=catalyst system efficiency below threshold.p1334=poor combustion cylinders 3&4. Points to DI cassette.

P1110 means problem with a turbocharger bypass valve.Check the first all hoses if OK change the valve.

P1312. I think its the DERECT IGNITION CASSETTE. and it cost like $200 At the dealership. Good luck

CODE P1312 -COMBUSTION DETECTION CYLINDER 1 2 OPEN CIRCUIT SHORT TO B+ POSSIBLE CAUSE -CHECK OUT PUT SIGNAL FROM CONTROL MODULE- CHECK FOR POOR CONTACT IN CONTROL MODULE CONNECTOR- CHECK HARNESS BETWEEN MODULE AND CONTROL MODULE. CODE P1334 -COMBUSTION DETECTION CYLINDER 3 / 4 OPEN CIRCUIT SHORT TO B+.YOUR POSSIBLE CAUSE IS THE SAME AS P1312.

P1312 is ignition coil knock detection cyl 1 and 2 and the cause is quoted as wiring open circuit/short to positive, ignition coil assy, ECM.
P1334 is as 1312, but cylinders 3 and 4.
The other thing to that would cause detonation too is low fuel octane causing detonation during acceleration. Or dirty fuel injector and dirty fuel filter. Timing would cause this but i don't think your timing is off since you can get it started. Recap, add fuel injector cleaner to your gas tank for the next 3 fill ups and try using a higher octane rated fuel like 91 and replace the fuel filter for now and see if there are any improvments. keep me posted, be glad to help.