Hello everyone, I am new to this, so please be patient. I would like to thank everyone in advance for any help you may give. I have a 1999 Toyota Corolla with a lot of miles! It has been a great work car. I started having some problems recently that I just cant figure out. My check engine light had been on for some time, but the car was running fine. The car has 300k miles on it. Never had a problem. In the mornings when the car is cold, or after it has sit for a few hours and then engine is cold, the car doesn't want to start. It is like it isn't firing or getting fuel or something. I pulled the codes and it gave me a P0420 and P0115. As I said earlier, the light had been on for a while with no problems. I cleared the codes and the light came on again with P0420. I get the P0420 code everytime the light comes on and the P0115 occasionally. Anyway, I crank and crank and finally I will get the car started. It will run really rough for a just a little bit and then smooth out. From that point on it will run just fine with no problems. I just put brand new NGK plugs and new plug wires on the car, and that didn't fix my problem. Any thoughts?
99 Corolla Problems Starting P0420 P0115 Codes
1 - 14 of 14 Posts
did you change your exhaust manifold by any chance?
Joined
·
1,917 Posts
It sounds like you have 2 separate problems. One, the cat is bad, or you have some cut vacuum lines. Two, your thermostat could be bad.
No, I have never had to do anything to this car.
I know the research I have done says the the P0420 is the emissions system and could be catalytic converter, exhaust leak, Oxygen sensor, and on and on. I don't think I have an exhaust leak. The P0115 code says engine coolant temp sensor malfunction. I am not sure if either of these codes have anything to do with my starting problem. I guess that is what I am trying to figure out. The car is hard to start, but once I do get it started it seems to run just fine.
Joined
·
1,917 Posts
The P0420 code won't hinder starting. A bad thermostat could though.I know the research I have done says the the P0420 is the emissions system and could be catalytic converter, exhaust leak, Oxygen sensor, and on and on. I don't think I have an exhaust leak. The P0115 code says engine coolant temp sensor malfunction. I am not sure if either of these codes have anything to do with my starting problem. I guess that is what I am trying to figure out. The car is hard to start, but once I do get it started it seems to run just fine.
Thanks for your help rollatuner110. That is good to know on the P0420. I would like to solve my starting problem and then I will dig into the P0420 code. I will replace the thermostat and see if that helps. The starting problem I am having though seems like it is not firing or getting fuel. Would a bad thermostat give the same symptoms?
Joined
·
1,917 Posts
You could have bad plugs and/or wires coming from the coil. But when you say trouble starting, it could be your starter as well. Check your battery as well.
Thanks, I replaced the plugs and wires and still have the same problem. It is like it is not firing or getting fuel though. It turns over fine, so I am thinking it is not the starter. When I finally get it started, it runs really rough for a minute or two then kick in a run fine.
Hi, I have a code reader and pulled them myself. I pulled them again today and cleared the codes, which turned the check engine light off. I ran the car for a little while and when the light came on, I immediately pulled the codes again. I had the P0115 code, but not the P0420 yet. This would indicate the coolant temperature sensor, but I have tested it using an ohm meter and it tested within the guidelines. Would this sensor cause this starting type problem? If it could, for $35 i will just change it and see. What are you thoughts. I have checked the proper coolant level, and it is fine.
David
wow nice
1 - 14 of 14 Posts
