Primastar Exhaust Leak

Uneven running and jerking on acceleration often point to misfires. I had a similar problem with my old Opel Astra, though it had a diesel engine. It turned out to be a leak in the exhaust system before the catalytic converter. The engine management system was going crazy trying to compensate for the altered readings from the oxygen sensors. Does it sound similar? When was the last time you had the exhaust system checked? Is the exhaust louder than normal?

A leak in the exhaust system? I hadn't even considered that. The exhaust doesn't sound obviously louder, but perhaps it's a small leak? How did they find the leak on your Astra? Did they use some kind of smoke test or something? I'm just trying to get a better idea of what to look for, or at least what to tell the mechanic to look for.

On my Astra, the mechanic used a smoke test to find the leak. It was a hairline crack in the exhaust manifold, almost invisible. Given your symptoms and the error codes, I'd strongly suggest taking it to a workshop for a proper diagnosis. Trying to find exhaust leaks can be tricky without the right equipment. Save yourself the time and potential for further damage.

Thank you so much for your advice! I took your suggestion and brought the Primastar to a workshop. You were spot on! It was indeed a small leak in the exhaust system. They found it with a smoke test, just like you said. Repair cost me 265€, which I was happy to pay to have it running smoothly again. I really appreciate your help!