So this has been a problem that appeared out of nowhere a month or two back, and I would start it up, wait a minute or two to warm up a bit, throw into gear and back out, but it would stall out, I had to bring rpms up to around 1500 and then put into gear and keep driving for about 10-15 seconds then I could come to a complete stop without it stalling, and it runs fine after that, only on startup after sitting for a few hours.

 

When was last tune up; how many miles on vehicle? Any codes??

 

No clue on any tune up, but it’s at 320k and no codes, I just changed the knock sensor and went through this whole process of changing every sensor, since I just got it running again.

 

I would start by changing plugs and wires with that many miles and no history of a change

 

Plugs, coil packs, wires all new, new IAC valve, tps, MAP sensor, crank and cam sensor all new.

 

So I have a p0420 code, and I know these are notorious for exhaust leaks, so I’ll try and fix that, especially because a couple bolts on the exhaust manifold are actually broke