Hello. I've reached my first issue with the infamous maintenance nightmare 355 Ran great off the trailer, parked it in the garage. Start it up, pull it out of the garage. Work on interior bits. Pull it back in the garage. Repeat for half dozen days. Replace stock muffler with topspeed pro1 challenge (basically straightpipe). Put back in garage. Pull out of garage: runs rough. idles at 1200 rpm. Tap gas, rough rev. Sounds and feels like misfire. Back in garage. Disconnect battery, let sit for 2 days. Reconnect battery. Fire up. Idles rough. Starts "coughing" like, sputters, not quite backfires... I'm about to start pulling spark plugs.
Should never, ever, absolutely never do that to a 95 355. Pull plugs, clean or replace all eight plugs. If that does not work, then we can talk next. I rather park it outside in the driveway, put a plastic bag over the engine, cover the car with 2 car covers, and leave it in the rain than to abuse the car by driving it 20 feet, 12 times. My 348 has been outside for two weeks now under 2 covers, untouched, unmoved, because of this exact issue. I refuse to start the car and move it 10 feet.
If in doubt, go to the last modification you did on the car. When you changed the exhaust, what parts did you remove/disturb/forget to reinstall
The exhaust was straight forward. No sensors or anything. Pop off the old, pop on the new. But look at the orange and white residue on my fourth plug wire :'( Image Unavailable, Please Login
Could be a lot of things. Plugs, wires, electrical connection, fuel, etc. While it is running start jiggling wire connectors, especially the fuel injector connectors and see if any of them aren't making a good connection. I had to replace several of the AMP connectors. That fixed a miss, but replacing plugs and wires made a big difference in smoothness.
All the plugs were dry with little soot. Cleaned them off anyway. The wires and connections all looked good (except for #4 with the rust residue) clean on both the coil and the plug ends. Reconnected the battery and fired her up. Sounded improved! For a few minutes... by the end of the 10 minute ECU relearning idle, the rpms had settled to around 1k and it was still muscle car sounding, but no longer coughing/sputtering.
Your new Top Speed Pro-1 is configured just like my OEM ANSA Challenge exhaust and so your F355 will sound just like an F355 Challenge... Image Unavailable, Please Login Image Unavailable, Please Login
bobzdar {Pete} has the Top Speed Pro-1 Challenge muffler on his F355 Berlinetta. It sounds like this... Yours will too.
I had a friend who bought a 95 355 with that essentially-straight-pipe set up. It was loud, it was obnoxious, and it was [he decided] uncivilized. He changed to Capristo Stage 2 and was much happier. I was happy with my Tubi muffler. The straight pipe reminded both of us why we did not like Harley Davidson bikes with no straight pipes.
I agree, Mitchell. The Challenge exhaust is loud, obnoxious and uncivilized. Its place is on a race car on a race track. When I'm on the track, just a small percentage of my senses are devoted to exhaust sound. I'm too busy doing other things in a prioritized fashion. Yes it's loud, obnoxious and uncivilized.
I agree, it's fairly loud and screams "look at me" while driving even conservatively... I had seen bobzdar's video but went with it anyway. The rumbly idle kinda threw me off because I didn't find any decent audio quality videos except for his 5 minutes of no stop sign corner-pulls. I may return to the OEM muffler if I get sick of the drone.
I find many aftermarket exhausts make the cars sound like muscle cars at idle. Its worse with the 348. Its hard to not like OEM on the 355.
