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Tried engine diagnostic check, but the ECM ain't talkin!

I bought a new-used 1994 Subaru Legacy wagon a couple weeks ago. It had the check engine light on but I needed a car fast and trusted the seller’s claim that he’d never had any problems and the check engine light was probably due to a malfunction with the electronic seatbelts.

I waited until I found a free diagnostic check coupon in the mail (today) and had it checked out at Midas.

The guy said they weren’t even able to “talk to the computer, the ECM,” which means “it’s got serious electrical problems, it’s not going to pass emissions, and, if I were you, I’d find this guy and get my money back. That’s why he unloaded it on you.”

Thanks for reading my story; now, the real question is whether this guy was right. How serious a problem is it that they can’t communicate with my computer? Can someone else do it and they just didn’t try hard enough because, after all, I was a free coupon customer? And, really, will it not pass emissions?

My next thought was to go to the Subaru dealership, but again, I’m concerned about the cost. I want to find out as much as I can beforehand.

Thanks so much to anyone for any thoughts!!

- Eri

No OBD1 code about seatbelts (none that I have seen). No communication concerns do tend to require a “computer” replacement,strange though the cars can run OK,OBD1 was not the best.

The emission question is related to how your State tests.

Well, this model Subby IS ODB-I. An ODB-II scan tool has no port to hook up to. You can pull the codes yourself by following the directions here:
If that doesn’t work, maybe you do need a new ECM.

Every car built before 1996 usually need to do a simulated road test for emissions checking. There is no need to ‘communicate’ with the ECM. It could very well pass emissions as-is. However, even some pre-96 cars can be failed automatically with the CEL on, depending on your location and state requirements.

Your mistake was buying a car with the CEL on. Why did you do that?

The seatbelt story is BOGUS. Seatbelts are not connected to the CEL. The seller lied to you, and you were dumb enough to believe him/her.

Emissions testing varies from state to state, but it’s highly unlikely that a car with a computer that won’t communicate, or a CEL that’s on, will pass the test. Where I live, the CEL is a no-no.

Take the car to an independent mechanic and get another opinion about the computer’s ability to communicate, and find out why the CEL is on (It’s NOT because of the seatbelts). Midas is a muffler shop, and you didn’t say you needed a muffler. You need a mechanic.

I’d avoid the Subaru dealer like the plague, unless you have deep pockets, which you don’t, otherwise you would not have purchased a '94 Subaru Legacy Wagon.

I wish you luck, but I’m afraid you’ve bought a car with problems that are going to cost more to fix than the car is worth. I suggest you think very carefully before spending much money on this car.

As someone famous one said, “Haste makes waste.”

Do the test to get the check engine light flashes. They may be rather fast, so, you may need somebody else to double-check the count.
Bring those flashed codes here for cussin’ n discussin’. Then, at least you could have an idea of the real problem.
In some states, you can force (legally) the seller to refund 100% of your money for a car which won’t pass emissions test. You could call DMV or the Emissions Test Station for details.

Here is a list of engines and car models which were fully OBD II certified in 1994 and 1995. The 1994 Subaru isn’t on the list.

You may have ripped that poor guy off! You won’t know until you get a price for the ECM. If you want to, you can change it yourself. I like my computer to be located just above the passenger’s right foot on the firewall. Start a new post if you decide to do the change yourself. You may have to remove the old one so the parts place can get a number off it. The other common lie if you ask somebody why he is selling the car he bought a week ago is that he wants to buy a minivan because he found out four days ago that his wife is pregnant. AFTER reading the other post, maybe someone can read your OBD-1 computer. I understand now that the first shop just can’t hook up.