Flash Code 18, OBDI Information Needed

[Axlander9289]

So I went to drive my '93 Festiva (5 Speed) earlier this week and found that it had a lopey, rough idle and a severe lack of power at low RPM. I attempted some diagnosis on it this weekend, and found that if I jumpered the fuel pump and ran the car with the VAF disconnected the lopey idle was still present. I have spark on all four cylinders at all times at all RPMs. I'm thinking my timing belt may have jumped a tooth, but I haven't checked the timing on it yet, and I don't have a compression tester. The manifold vacuum is at a steady 15 inches Hg at idle which is a little low, but fits with a timing issue, also I'm at an elevation of about 3000 feet.

I never had a check engine light on, but when I checked for codes, I would sometimes get a flash code 18. I cannot find a definition for this code, including in the stickied posts in this forum, but what little information I can find says to check the base timing. Given the symptoms present, I wouldn't be surprised if the timing belt had jumped a tooth. I don't konw a lot about OBDI systems. Most everything I've done driveability diagnosis on has been OBDII. I'm just curious how the OBDI ECU can know a timing issue is present without a crankshaft or camshaft position input. Does anyone know what conditions this code sets under or just a definition for it? Thanks in advance guys.

[FB71]

it won't know if it's a timing issue; all sensing done thru the dizzy. OBDI is primarily integrity detection, doesn't really monitor performance of the circuit like OBDII. Don't know what 18 is off the top of my head, but I can check in the morning.

[TominMO]

According to this page below, there is no Code 18. Could you have mis-counted, and it's really a 17? Which would be O2 sensor.

http://www.troublecodes.net/Ford/88-951325/

[Axlander9289]

According to this page below, there is no Code 18. Could you have mis-counted, and it's really a 17? Which would be O2 sensor.

http://www.troublecodes.net/Ford/88-951325/

I thought the same thing when I saw the list. I counted three times. Weird, right?

[TominMO]

I thought the same thing when I saw the list. I counted three times. Weird, right?

What about 28, i.e., two long flashes followed by the eight short ones.

Another thought: did you learn to count under Common Core?

[tooldude]

Interesting, since the carbureted cars can have code 18 for Air Bleed Control Valve. Could your car have had a past operation or maybe a current identity crisis, or possibly the computer can't count?