Hey Scotty, I have a 93 Celica with 3sge engine and 92k mi. On cold start (bellow 40 F), car starts fine and goes to 1800 rpm but then rpms drop to 1500 and car spusters and misfires, no codes, and while doing that, little bit of black smoke coming out of exhaust (like it’s running rich), after like 20 seconds, all this stops and operation goes back to normal and rpm go up again to 1800 and runs smoothly. I have an external head gasket leak, oil seeping on the block and driveshaft for the past two years and 40k miles, temperature never in the life of the car got past haflway on the gauge. Also when up to temp, there is a little bit of white smoke coming out of exhaust(I know, when cold, little bit of white smoke is condensation and normal), could that be that head gasket is starting to leak in one or more of the cylinders? Are those two issues anyhow linked together? Thanks

gasket and or head are probably going. I would put a used japanese engine in it myself as I did for my son in that same car

@ScottyKilmer Thank you. 2 years ago, the coolant was all corroded so I flushed it and now i keep it clean. Engine was never overheated so shouldn’t be cracked head but rather a blown head gasket. Engine swap is out of question since doing that is more expensive that buying another car. Thanks again