Emissions & Computer failure

Hi,

I have a 1998 Saab 5 speed manual, turbo.



We have tried several repair shops, but cannot find anyone who can make our engine light go off. Sometimes it will go off for a little while, but then it comes back on.



It is due for emissions inspection and the inspector (in Washington DC) said that because the engine light is on, they cannot communicate with the car’s computer & so the car fails.



I have been told that repairing or replacing the car’s computer is enormously expensive.



Any suggestions?



Thanks!

Ally

You mean there isn’t a Saab specialist anywhere in the D.C. area?

Search the phone book, the internet, or anywhere you have to search, but find someone familiar with Saabs. Surely there must be one somewhere near you.

You need someone who will tell you why the light is still on, and then fix whatever is causing the problem.

A quick search in the Cartalk Mechanics Files turned up ten Saab repair shops in the DC metro area.

You have not provided any info about what if any codes exist, what has been done or not done, etc.

Take the car by a local auto parts house (AutoZone, Advance, O’Reillys, whomever) and have them scan it. They will do this for you free and it only takes a few minutes.
Post any results back for discussion.

I think blaming the computer at this point is a bit far-fetched.

Thanks. We’ve been to four mechanics, three of whom did ‘computer diagnosis’, and no one can get the light to go off. Maybe they are lying to me, and they don’t really have the right kind of computer hook-up (that is what a saab dealer suggested to me). I will look at the paper work & see if any computer codes are noted on it.

OBD-2 Emissions Controls are standardized throughout the industry. If the CEL is on, there WILL be codes stored that can be read. Post the codes and maybe someone can help…How many miles on this car?

I’ll plan to take it to shop to find out the current codes.

I would like to say this started when the radiator went bad in March of this year, but in reality this engine light has been going on & off for no apparent reason (according to my usual mechanic who is usually quite good) for a year or two now. Also, just yesterday, the instrument panel went dead. That is, the panel directly in front of the driver (not including the clock & radio, slightly to the right). This panel started up again after I turned the car off & then turned it on again. Today it was working. Also, for some time now, the rpm indicator has intermittently not worked.

Recent repairs include: PCV valve replaced, & turbo vacuum tube repaired/replaced.

One slightly misfiring spark plug can set O2 and converter codes and it’s very easy for even an experienced tech to try and bypass the simple stuff and assume the problem is worse than it really is.
As a long time tech I don’t mind saying this is true for me also and sometimes it really takes some serious pushing to shove the worse case scenarios to the back of the mind and follow the KISS rule. (Keep It Simple Stupid)

Some years back a local and now retired Ford dealer I used to do sub work for sold a used small Ford pickup to a gentleman who lived almost a 100 miles away. Within several weeks this truck had quit (instantly) the elderly gentleman 3 times; leading to a tow each time to a local shop. A hundred or so dollars the first trip, 3-400 the next, and the last one involved 800 dollars worth of valve springs and rocker arms.
The last one was especially ridiculous and the gentleman was about in tears before calling the dealer who sold him the car.

They towed this truck a 100 miles (after quitting the 4th time) and had me look at it.
You know what the entire problem was? A burnt fuse connection for the electric fuel pump and it was very obvious. Weeks of aggravation, 4 tows, hundreds of dollars worth of not just guessing but very bad guessing, and the cure was a 30 cent fuse. See my point?

The light being on does not have anything to do with being able to communicate with the computer. The code that says that no communication is happening is the reason. If the Saab has no code for that, the computer is usually gone when no communication is possible. If there is a code for that, and you get that code, replace the computer.

You will find out nothing anyway until the new computer is installed.

Hi, Thank you everyone for your thoughts on this. My mechanic yesterday said that the current computer code signals a problem with the idle. He cannot figure out what to do about that. From what I understand, the idle is supposed to be controlled electronically.
Any suggestions?
Thanks!