2004 Forenza Running rough after Catalytic Converter replacment.

GLIATTALL

MEMBER
2004 SUZUKI FORENZA
170,000 MILES

I recently bought this 2004 Forenza from my neighbor. I was throwing a code. He said he had it check and it needed a converter. I never actually had the code checked myself to make sure. "I know, not very smart." But I replaced the converter and disconnected the battery to reset the code. Now the car is running like crap. Sputtering at idle. Pull on the throttle a little and it fluctuates. I'm wondering if the computer needs to reset the air/fuel trim or something. Also, trying to figure out how I"m going to get this thing through its drive cycles. I drove it around the block. It was ok at first and about 1 mile in it started running rough. Also, engine light is flashing now. I'm worried about driving it to much like this. Not sure what to do now. And I totally regret not checking the code myself. Any suggestions where I should be looking?

Thursday, May 24th, 2012 AT 10:28 PM

5 Replies

ASEMASTER6371

MECHANIC
52,796 POSTS

The converter had nothing to do with threpair. The engine has a missfire that is making the light flash. This may be the reason for the failing converter to start with.

Do not ever disconnect the battery like that. The light would have cleared itself after it passed its own self test without effecting the monitor status.

Get the code checked by a shop this time and find the exact failure.

Roy

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Thursday, May 24th, 2012 AT 10:31 PM

GLIATTALL

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11 POSTS

I didn't specify properly. The original code was a solid engine light. My neighbor had it checked at a Suzuki dealership and they told him he needed a converter. The flashing engine light or misfire didn't start until after the converter was replaced. Also, it doesn't start flashing until it warms up.

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Friday, May 25th, 2012 AT 1:06 AM

ASEMASTER6371

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Ok, but replacing the converter did not cause the light, the flashing light or missfire is what caused the converter to fail. You need to have the system checked to find out why the engine is missfiring or the new converter will be destroyed as well.

Roy

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Friday, May 25th, 2012 AT 1:14 AM

GLIATTALL

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Tried to have a buddy use his scanner to check the code. Funny thing is it said it didn't have a code. I'm going to have it scanned at a shop. One question I have is before I replaced the Cat, the car was running good. After I put the Cat. In is started running rough. And then I made everything worse when I disconnected the battery. I was just wondering why would it go from running good to rough by replacing the Cat? Is it an air/fuel thing? Or could is just be whatever was causing the code is worse with the new Cat? It just seems weird that putting in a nice clean Cat. Would cause it to run rough. I understand that there is an underlying issue that needs to be addressed, but I was just wondering what would cause it to run rough with a new one when it ran fine with the old one? I'm going to try and get it scanned this weekend. Not sure if I will be able to with the holiday. Thanks for the help.

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Saturday, May 26th, 2012 AT 1:38 AM

GLIATTALL

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Just to follow up. Heres the story. When I was changing the convertor out we had a heavy rain storm. I forgot to shut the hood and had enough water get around the spark plug wires to cause the misfire. I did a good tuneup and its running pretty good again. I did the throttle relearn but the idle seems a little high. I have no codes and I'm trying to get the drive cycles reset so I can get inspected. Only thing thats not ready is Catalyst monitoring. I figure I just need to drive it around a little more. Hopefully I don't get a code back after it resets. Any suggestions on how to get the catalyst monitoring reset?

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Wednesday, June 20th, 2012 AT 6:13 PM