After using Cat Cleaner the engine will start but does not stay running?

2013 BUICK VERANO
130,000 MILES • 2.4L • 4 CYL • 2WD • AUTOMATIC
Avatar
CYBERTIGER99
  • MEMBER
  • 4 POSTS
It always had a p420 code, but the car ran fine at all speeds. Added Cat Cleaner to try to clear code with no luck, but right after cleaner was added engine was started and wouldn't stay running. You had to keep pumping the gas pedal all the while keeping it at 2,000-3,000 RPMs to keep it from shutting off. The engine was cold. As the engine warmed up it would run better. When the gauge hit operating temperature (180-190?) the stalling/shutting off stopped and you could drive the car with no problems until you stopped and turned it off again and let it cool down. Then I started the car again and the symptoms returned. The shop I have the car at replaced the fuel pump and Map or MAF sensor(?) Didn't solve the problem. They don't know where to look next. Any clue what could be wrong?
Apr 20, 2023 at 4:58 PM
Advertisement
Avatar
STEVE W.
  • CERTIFIED EXPERT
  • 15,113 POSTS
I'm guessing it still has the same fuel in it with the cleaner in it? If so, I would try using the fuel pump and a disconnected fuel line to pump that nix out, then dump in some fresh fuel. See if that improves the problem. If it does, then it may be that the additive caused a problem with the fuel system and may have damaged the O2 sensors or as the converter wasn't working before it may now be clogged with the crud that the cleaner stirred up. To see if that is the problem disconnect the exhaust or use a pressure gauge to measure the restriction in the exhaust. I suspect the final repair will involve replacement of the converter and a fuel system flush.
Apr 21, 2023 at 1:44 PM
Avatar
CYBERTIGER99
  • MEMBER
  • 4 POSTS
Steve, i know a little about cars and I told the mechanic working on it, it looks like it is fuel related and why he hasn't cleaned/emptied the tank is unknown. I'll show him this suggestion and see what he says. I'll keep you posted if warranted Thanks for your timely response. Don Swallow.
Apr 23, 2023 at 9:21 AM
Advertisement
Avatar
STEVE W.
  • CERTIFIED EXPERT
  • 15,113 POSTS
Good luck. The way it runs reminds me of gas that got diesel in it, wouldn't run very good cold but once it got heated up it ran just fine. It sounds like the cleaner acts the same way, which is why I would start with it. Then test the rest.
Apr 23, 2023 at 7:05 PM
Avatar
CYBERTIGER99
  • MEMBER
  • 4 POSTS
Well, the misfire was solved. The downstream (non-OEM) o2 sensor had failed and was acting up I guess the Cataclean had no affect after all. Although the CEL has come back on giving a P420 code again. Oh well, at least I can drive the car now, until I address that problem.
Apr 29, 2023 at 12:38 PM
Avatar
STEVE W.
  • CERTIFIED EXPERT
  • 15,113 POSTS
Could still have been the added juice that got the sensor although I don't have much luck with non OEM sensors holding up very well. Not saying it would be okay to do but if you are not in CA, you could try the spark plug non fouler trick. Lots of videos showing it.
Apr 29, 2023 at 10:36 PM
Avatar
CYBERTIGER99
  • MEMBER
  • 4 POSTS
Thanks again Steve for the advice. I wish you well.
Apr 30, 2023 at 9:32 AM
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,854 POSTS
STEVE W. is one of our best! Use 2CarPros anytime, we are here to help. Please tell a friend.
May 3, 2023 at 10:05 AM