Today is the first real drive for the car. I ran a friend down to Arena motors to pick up his 308. The '95 355 ran fine. The PO told me that occationally the slowdown light would light, but it would always go off & he never could find out why. His mechanic thought it was due to the straight pipes. On the way, the 5-8 light came on. It didn't go right off, so I pulled over & shut the car down. THen restarted it. No more light. It ran fine for about 20 miles when both the 5-8 CEL & Slowdown came on. then 1/2 the engine shut down. the lights went out. about 15 seconds later, the power returned. This happened a bunch but since I was close to Arena motors, I continued. When I got there, he noticed the bypass was wired open and suggested the heat sensor was flaky sensing the GHOST CATS were overheating & to shut 1/2 the engine down. He didn't have another sensor so it'll be ordered. But he also said it might be condensation or just general lack of use since the car hasn't been driven regularly. On the way home, I made it 30 miles before the engine started acting up. slowdown light on, CEL on, loose bank. stop for 5min, restart - it's fine. is it in the workshop manuals? if it's in the parts manual, anybody have the manual in PDF, TAV # & Part # of this sensor so I can see where it is? Is it possible to clean it temporarily until a new one arrives? Thanks.
You need to pull the CEL code and it will tell you exactly what is wrong. My money is on a faulty cat ecu which will trigger both the CEL and Slow Down lights.
Catalyst temperature ECU, part # 69. You can try swapping the right and left ones and see if your problem jumps to the other bank of cylinders. Image Unavailable, Please Login
Do I check the ECU error codes with engine idling or off? when off, both ECUs give me a 1211. When running, One side gives me a 1211, the other I'll have to do again 'cuz I think I futzed it up trying to advance to the next code. I forgot this is an Italian machine and you have to take your time & have an esspresso between button pushes
I took the car to my mechanic for the CEL lights coming on & Slowdowns (car only has straight pipes) He tells me there is low compression in 2 adjacent cylinders (150), the rest were around 200: his educated guess - valve guides. I had a PPI done on 9/14/11 before I bought it at about 21,500 miles. No issues found. As such, they didn't see the need for a leak-down. I have the prior service histories: prior PPI : 1/14/09 18,396 miles “Very pristine example with no issues” Last major: 1/17/09 front 210 200 205 200 200 205 205 205 The guides/valves were replaced 2/12/2008 @ mileage 17,919 I'm only a backyard mechanic. But I wouldn't think an excellent condition car could burn through previously replaced valve guides in 4K miles or under 3 years. Thoughts?
Clyde, another possibility for low compression is deposits on the valves. This can happen if the car is driven too sedately. Try some GM Top Cleaner run through the intake system to burn out the deposits. This may restore the compression.
I believe so. "But officer, I have to drive it hard for the Italian Tune-up or my valves will gunk up!" THink this might happen with just 4K miles? Plugs fouling, sure. But valves?
Im sorry to be the dick here Clyde But your previous PPI isnt worth the paper its printed on. There is no way they gave your car a thorough PPI and missed all these issues. 1 or 2 minor flaws, like rust in the door sills or something,. i can understand being over looked. But banks cutting out? CELs and Slow Downs popping up every 30-50 miles? Low Compression in a cylinder? Something doesnt add up...
If it were my car I would... Check headers for leaks cause your getting close to their 30K service life if OK then.. Italian tuneup Check the O2 sensors are good Check the cat ECU is good Check all wiring connections and engine grounds (Maybe time to install the SRI connector kit.) Do a proper leakdown test Doubt its guides giving low compression readings
Clyde, Sorry to hear of your troubles, but I think you should get another opinion from still a third expert mechanic who comes highly recommended. Have this third mechanic go through the entire car and find what is wrong. We know of several great mechanics so take your pick. Call me if you want to chat. David
There is no way 2 cylinders lost 50LBS of pressure in 4K, sounds to me like he didnt have the compression gauge sealed correctly. The factory guides were a very soft metal when they were replaced they use sintered steel the car will fall apart before those guides go bad.
Hi Clyde First thing is you do not check valve guides using either compression or leakdown tests. f355spider makes a good point concerning any carbon stuck to the valve or seat. A compression check must be done properly...this test simulates cylinder pressure in a dynamic state(what would actually be when u are driving the car) Leak down is a static test for cylinder sealing. In the old days when we were pushed and did not have the time to do a leakdown we added a teaspoon full of motor oil to the off cylinders....this will tell u if it is a ring or cylinder liner problem. Valve guides(esp. the bronze) can go bad in 4k but it would have to be subjected to extreme conditions which are more common to racing and not a street driven car. If f355spiders suggestion does not produce results then don't spend the money to do a leakdown test just go ahead and pull the engine. If the bypass was wired open(or if headers are compromised) my opinion would be a liner/rings have gone beyond spec. Don't worry about headers and anything else right now just address the 2 cylinders that are sub par.
I'm praying for this! I believe this is the next step the mechanic will be checking this wasn't the case. And the bronze were replaced a couple years ago according to the car's documentation. it is agreed. I visited her today. And with such wonderful weather, I soooooo wanted to take her out for a drive!
The bypass is to quite the engine down at lower RPM's most are wired open as mine has been for years, should have no adverse effect on the engines performance.
The party is just starting! I hate to say it. But issue #2 is coming at you like a rabid bill collector. Thank God for this website! It's saved me some coin. QUOTE=ClydeM;140821789]Today is the first real drive for the car. I ran a friend down to Arena motors to pick up his 308. The '95 355 ran fine. The PO told me that occationally the slowdown light would light, but it would always go off & he never could find out why. His mechanic thought it was due to the straight pipes.
Sorry to hear about the problem you are facing. If you are lucky enough to get out of this without a bottom end rebuild do yourself a big favor and replace those original headers.
Not uncommon at all........as a matter of fact I was talking to a 355 owner last night that had this problem.
Ok, the CEL lights & slowdown lights were fixed by replacing the Cat Temp sensor & crank sensor. Arena Motors hooked up his SD1/2/3 which flagged the bad sensor. The flashing dashboard said MAFs. My confidence isn't too high on the flashing dash I took her through NJ inspection. She failed. Emissions. I've just purchased Prospeeds. I'll do some sound clips & photos before & after. Two other questions - I replaced the driver's door lock that was broken. Every once in a while the locks will try & lock 3 times, then give up. It's happened by just me closing the door without touching the locks. Manually push them down & they are fine. Use the key & they are fine. Ideas? Lastly - my 308 and many others (inc Mondi, 328) have a slight engine miss/stumble at idle - but not all the time. The 355 does it too. Do you folks get very smooth idles or is the miss an inherent Ferrari thingy?
No stumble or miss normally. I have owned a 308, 328 and 355. Whenever I had such symptons in the past, it was either plugs, extensions or wires. On the 355 the wire and extension are one peice. I have had a miss at idle before, and had a fouled plug on the 355, caused by water intrusion into the plug well. New plugs and gaskets, including the foam block at the back end of the cam cover, and all was well.
Well now this is embarassing - Yesterday pulled into a gas station & the gas cap was stuck on. The area is too small to get your hand in there & get a good grip on it. A mechanic used an oil wrench taped up to get it off without a whole lot of difficulty. Today - same thing happened. The gas station attendant had a good laugh. I'm guessing the pressure of the tank is causing it. I've put some anti-seize on the threads. Anybody have any other suggestions?
Hi Clyde. Thisnhas happened to me as well. Usually if I was out driving for a while. Not quite to the degree of using a wrench but quite a few strong attempts before it finally came off. Let me know if anti seize works. Thanks. Chris
