| Author |
Message |
Bill Sebestyen (Bill308)
| | Posted on Sunday, October 14, 2001 - 3:01 pm: | |
Magoo,
I wonder if it was a universal cat or if the 348 design incorporated an off the shelf US design. My 78 308 cat is pretty unique and I looked pretty hard to find one at a reasonable price. I also couldn't find a univeral cat that I felt comfortable with. They all appeared to require fabrication to fit and it's a very tight volume. Bill |
magoo (Magoo)
| | Posted on Sunday, October 14, 2001 - 11:17 am: | |
Bill, That is something I never heard about. Recycling cats. Great savings. However G.M. did have a process in the 70's to replace the platinum coated beads in the convertor. That could be done in the shop and on the car. What I was referring to was someone had said that you could buy the cats,new cats, at a Ferrari dealer for $140.00. Just seemed to be incorrect considering how they charge for everything else. |
Bill Sebestyen (Bill308)
| | Posted on Sunday, October 14, 2001 - 8:31 am: | |
Magoo,
Your old cats can be recored, which a local shop had done for my 308. the total cost for 2-cats was about $250, including UPS ground shipping. I specified 2-way cat material for my carburated car.
The process is pretty straight forward. They shipped it to a place in Virginia, I believe. There, they apparently make a simple jig to preserve the length and alignment of the flanges, cut the up-stream end of the cat casing off, and extracted the damaged (melted) core. The new core material block is shaped to fit, inserted into the casing, the end wall is re-welded, the casing is painted, and the cats are shipped back to the jobber. Bill |
magoo (Magoo)
| | Posted on Sunday, October 14, 2001 - 12:38 am: | |
Bill, Excellent diagnosis and breakdown on the two type cats. Honey comb, Chrysler used it for years and it was a disaster. Heated up broke down and clogged the exhaust system. However can these cats. be bought at a Ferrari dealer for $140.00 bucks. I have doubts about that price. |
Krister Ripstrand (Krister)
| | Posted on Tuesday, September 18, 2001 - 5:08 am: | |
Bill - Excellent posting. I'll keep it in my personal library. |
Bill Sebestyen (Bill308)
| | Posted on Monday, September 17, 2001 - 6:55 pm: | |
I did some research on cats when I realized I needed them to pass CT emissions testing and they had been removed from my 308 by a previous owner.
Cats are generally available in two flavors, 2-way and 3-way. 2-way cats are fitted to carburated cars and 3-way cats are fitted to fuel injected cars. 2-way cats control HC and CO. 3-way cats control HC, CO and NOx. Fitting a 3-way cat to a carburated car will soon fail the NOx capabilities of the 3-way cat which requires a near stociometric mix of air/fuel to remain healthy. Carburated cars cannot provide this fine a mixture. A fuel injected car with an oxygen sensor feed back loop is required.
Cats typically fail when an excess of fuel is present in the exhaust. This causes temperatures to soar and reach a point where the catalyst matrix begins to melt. If you look into the end of a catalytic converter, you will see a matrix of catalyst material. This monolithic block of material looks like a honey comb except instead of hexogonal channels it is manufactured with rectangular channels, parallel to the direction of gas flow. When this monolithic block gets hot enough, the material melts and becomes an obsturction to the exhaust gases. This condition will likely increase temperatures even more for a given driving condition and the 1-4 light will come on at lower and lower power outputs. So, if core melting is present, it's time to replace the cat(s).
A thermocouple is provided by Ferrari to measure the internal temperature of the cats. A thermocouple is a very simple device that produces a very small voltage (in the low milivolt range) proportional to temperature. When a preselected temperature (and ultimately a preselected voltage)is reached, the warning light is activated. Presumably, the light is activated before damage results.
If your 1-4 warning light seems to come on more and more often, then it is probably time to replace or recore your cats. Before doing this however, you might want to ensure the thermocouple connections are sound, but I cannot envision a scenario where a thermocouple will produce a voltage greater with a loose connection than it will with a tight connection. I hope this sheds some light on this often merky subject. Bill |
Herbert Edward Gault (Irfgt)
| | Posted on Monday, September 17, 2001 - 6:21 pm: | |
I believe they meant they had a stray cat that they would sell for $140.00 |
magoo (Magoo)
| | Posted on Monday, September 17, 2001 - 5:22 pm: | |
Hey Guys, I haven't checked, but a cat converter for only $140.00 from a Ferrari dealer? Seems unbelievable. Magoo. |
MADE100 (Noelrp)
| | Posted on Monday, September 17, 2001 - 4:39 pm: | |
Since we now know that the problem could be the ECU or the CAT (or perhaps both) and the CAT is about $140. How much is the ECU? Is the ECU the aluminum box behind the seat?...I hope not.
Thanks,
-noelrp |
Mark McKenzie (Redcar)
| | Posted on Monday, September 17, 2001 - 7:59 am: | |
Update: While driving over the wknd, the same "ck eng 1-4" came on within about 10 miles, but only for a few seconds, car was warmed up, but certainly not hot, and while the light was on it continued to run fine, no noticeable loss of power. Then for the remainder of the day, no light at all. Car ran perfectly. Maybe it fixed itself? I'll keep an eye on it. Thanks for the help. Mark McKenzie |
Krister Ripstrand (Krister)
| | Posted on Monday, September 17, 2001 - 7:55 am: | |
KH - Not necessarily. According to my discussion it is more lightly that faulty cats are indicated by the red "Slow dwn" warning lights instead of the yellow "Chk eng" warning lights. Just keeping the discussion going, maybe interresting some other guys/girls, since this is a seemingly common problem with the Ferrari engines. BR - Krister |
KH (H00kem)
| | Posted on Sunday, September 16, 2001 - 9:19 pm: | |
Like I said, replace the CAT and the problem will go away. KH |
Krister Ripstrand (Krister)
| | Posted on Sunday, September 16, 2001 - 4:53 pm: | |
Actually, in my manual it says that the "Chk eng" lights are not in use (Euro -92 348 engine). Obviously the problem I refer to is connected to the "Slow dwn" warning lights. Also in my WS manual I can not find anything about the "Chk eng" warn lights. The "Slow dwn" warning lights are directly controlled by the measurred temperature after the cats. Flashing occurs when temp is too high at 900+-20 deg celsius (1652+-36 F) while steady light shows that temp has reached 940+-20 C (1724+-36 F).
Obviously your yellow "Chk eng" lights are in operation, and a probable cause, from experience with other cars yellow chk eng warning lights, would be that the ECU through the oxygen sensor (lambda sond) is reporting fuel-air mixing ratio untolerated values. The oxygen sensor is located directly before the cats.
Theory (my own): A faulty reporting oxygen sensor, causing yellow chk eng warning light, can not pin point the cats as being out of order (pre cat sensor). Cats are completely passive devices which has to be exchanged in due time. Faulty cats would show up by excessive temperature after the cats, if the cats causes the exahust gases not to pass easily or if special measurement equipment would show excessive HC, CO or NOx gases. In Sweden HC and CO values are measured yearly to check for faulty cats. Summing up, would say that there is something wrong with the fuel-air mixing ratio monitored by the oxygen sensor.
In this context we must also be aware of that the ECU's where upgraded from Bosch Motronic 2.5 to 2.7 from ch# 86406 . I have the 2.7 version, and there might be a difference regarding the usage of the yellow "Chk eng" lights.
Anyone, any more experience with these two types of warning lights? |
Frank Parker (Parkerfe)
| | Posted on Sunday, September 16, 2001 - 8:12 am: | |
It sounds a lot how my TR did when the Cats were going bad. |
Mark McKenzie (Redcar)
| | Posted on Monday, September 10, 2001 - 9:48 pm: | |
Thanks for the advice. I'll keep an eye on it. What is the relationship between the yellow "ck eng" and the red "slow down", which I've never seen? Would the Cat cause the "slow" and the ECU cause the "Ck"? Are the lights progressive? Can you go directly to the red "slow"?
I haven't driven since, but the car seemed to run perfectly, even whilst the light was on.
Thanks again. Mark McKenzie |
Krister Ripstrand (Krister)
| | Posted on Monday, September 10, 2001 - 6:19 am: | |
Mark - Before exchanging any parts some tests can be performed thanks to the independant electronics around the 1-4 and 5-8 cylinder banks respectively.
The problem you refer to is one of the most usual ones on the 348 engine and several threads discusses it. The test I performed in this context is described in the following thread http://209.196.179.161/discus/messages/112/2095.html?.
regards /Krister |
KH (H00kem)
| | Posted on Sunday, September 09, 2001 - 7:07 pm: | |
I had the same problem. I'll bet when the light comes on the car looses its punch and kind of acts like it is going to stall. I replaced the CAT for the 1-4 bank and it solved the problem. You can buy the CAT from any Ferrari dealer (about $140) and it is an easy part to install. KH |
David Albright (Dalbright)
| | Posted on Sunday, September 09, 2001 - 6:53 pm: | |
I had the same issue last year. It would do the same thing. It progressively got worse to the point where the car was shutting off. It never stranded me, but did scare me a bit. I had FOW check it out and they replaced the ecu's. No problems since then.
ps The car was shutting down because the ecu thought the cats where over heating. |
Mark McKenzie (Redcar)
| | Posted on Sunday, September 09, 2001 - 5:46 pm: | |
While driving my '90 348 along the highway today, the "ck eng 1-4" light lit up for about 60 seconds, then shut off. No other symptoms at all, oil & water temperatures were low, and the car continued to run perfectly?
Any ideas? THANKS Mark McKenzie |
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