We are in the home stretch, but the car may have some unresolved mechanical issues.
When I picked up the car, it had P0441/0455 faults. I replaced the purge valve and gas cap with OE parts.
I want to verify there are no leaks in the EVAP system. So, I smoke-tested the EVAP system from both the service port and the fuel filler.
Although I was unable to find any smoke AND the car’s EVAP monitor shows complete, my smoke machine says I still have a 0.25mm leak:
Any ideas?
Next, long-term fuel trims are high at idle but are near perfect under high engine load. At idle, they are between +12 to +15%. I had the injectors cleaned and flow-tested, I checked the injector seals for leakage using brake clean (none found), and also pinched off the purge and booster vacuum lines. Nothing helped. So, I smoke-tested the intake:
Unfortunately, no leaks were found. Again, any ideas?
Then, I decided to tackle the worn exhaust donut gasket. This is the gasket that seals the exhaust manifold to the catalytic converter.
Here is a picture of the old gasket:
Unfortunately, I also found significant damage on the catalytic converter flange:
Not sure how this happened. I have replaced many of these gaskets and this is the first time that I have seen one with damage. The sealing surface felt like a cheese grater. I tried reassembling the connection with new spring bolts and multiple gaskets, but this resulted in a noticeable exhaust leak at idle.
So, I made a trip to the local muffler shop:
The tech wanted to try grinding down the peaks on the flange before attempting a flange replacement. I gave him approval to do so. He told me to reinstall the catalytic converter with a small amount of Permatex Ultra Copper on the gasket. Not exactly my style, but I did as I was told. After allowing the RTV to cure overnight, I started the car and was surprised to find the problem resolved. I even smoke tested the exhaust and verified no leaks at this time. We’ll see how long this lasts.
Lastly, I performed a headlight restoration. I DA-sanded with 320, 500, 800, 1000 and 3000, followed with 2 coats of 3M headlight clear coat.