93 1.8 ltr runs rough when warmed up

[trox]

93, 1.8 ltr runs rough when warmed up, OK when cold. Replaced my intake duct cuz it was cracked up and ran out of duck tape. Plugs look good, wires are fairly new, O2 sensor was replaced 3 years ago. Check Engine light is on constant now. The Check Engine light used to come and go occasionally and when it went out, you could feel the difference immediatly. I would like to check my codes but I have a different DIAGNOSTIC plug to what I have seen on my other Fords. I took pictures of the DIAGNOSTIC box, but this forum won't let me put them in the thread, it's located on the drivers side of the engine bay, beside the wiper motor in the corner. The cover of the box says DIAGNOSTICS right on it. I've looked everywhere for another TEST connection but see none. Does anyone know which pins to short in this box to give me codes? If anyone would like to see this box, I can e-mail the pictures.

[Davescort97]

My manual says the EEC diagnostic or self-test connector is located behind the battery in the engine compartment. On the 1.8 engine testing with the check engine light connect the EEC STI terminal to ground with a jumper wire.
There are 3 rows of connectors on one side and 2 rows of connectors on the other side. Disregard the 2 rows of connectors. On the 3 rows of connectors are: lst row--5 terminals, 2nd row--7 terminals, 3rd row--6 terminals.
The EEC STI terminal is the 2nd terminal down on the first row. The ground is the 7th terminal down on the second row. No connections are made to the 3rd row of --6 terminals

O. (KOEO) Key On Engine Off

Turn the ignition on. Leave car off. Disconnect and reconnect the STI terminal jumper wire. The check engine light will flash. Count the lst set of flashes and the 2nd set of flashes. For example two flashes followed by 3 flashes would be code 23. There is a 4 second delay between codes. The codes will appear in numerical order, repeating once.

C. Continuous Memory

After the KOEO codes are reported turn the key to the off position. Start and run the engine at 2000 rpm for five minutes to warm up the EGO or HEGO sensor. Then turn the engine off. Wait 10 seconds and restart the engine. Read codes.


R. Engine Running

Start the engine. The first part of this test makes sure the system can advance the timing. Check the ignition timing. It should be advanced about 20 degrees above base timing.

Shut off the engine. Restart it and run it for 2 minutes then shut it off for 10 seconds before restarting it. The Check engine light should flash 3 times., then show an engine code. After a pause there will be 1 flash, the signal to blip the throttle so the system can check throttle component operation. After this there will be a pause, followed by the Engine Running codes which will appear in the same manner as before, repeating twice.

[trox]

Thanks for the response. I have looked the engine bay over from top to bottom and find no test plug like the one used on my 91 explorer, 89 escort, 95 bronco or just about every other old Ford I've had, seen or worked on. I have a code reader for that plug and have used it several times. What is this box marked DIAGNOSTICS in clear view of GOD and everbody for? I wish I could send a picture somewhere so you could see it. O'Reileys haven't seen it before either. By the way, I replaced the O2 sensor last night and it still sputters like crazy after about 10 miles to work and is getting worse. With no way to test, I'm wondering what sensor may be the next most likely candidate. I could change the wires but I don't think they would throw a code. OK.... I was on the way home and it ran like crap even cold so I got a set of wires and put them on in O'Reiley's parking lot. It runs a lot better, they definetly made a world of difference. I asked to look up when I bought them cuz they have lifetime warranty. They were less than a year old. Now I'm running better but I would still like to get my Check Engine light to go out. I need to read the darn code. That would surely help my gas mileage out. As it is , I expect to get back to 30MPG now.

[trox]

OK, the best answer yet came from another forum that takes pictures. It looks like a MAZDA DIAGNOSIS box to the responder from Ford Forums. I'll be searching the Mazda forums for help now. Let you know what I find, if I find anything.