maybe this is why mine doesn't work. EEC is 87/88, engine is a 90. Waiving the white flag.There was a long thread several months ago on this exact subject. The cars with factory check engine lights in 87 & 88 were the California emissions cars, probably because California required it. Ford didn't make the light operable in the 49 state cars until they put mass air across the board in 89. If a non California 87 or 88 car has a light, it has most likely been changed to mass air and had the light installed. The code reader is the easiest way to get the codes, but I'm too cheap to spend the money on something I can get for free with a test light.
Even if you have the light in your car, you still need the code reader or have to jump the wires under the hood to get the codes, the dash light just takes the place of the test light or meter in reading the codes. And it lets you know there is a code in memory. But you have to have the mass air computer to operate the light. The speed density computers are not set up for turning on the check engine light. I just try to check for codes every so often to see if there are any regestering, like maybe at each oil change or so.
I did check the bulb and buy a scan tool a a couple weeks ago. This car a mix of three different years, a lot of the wires are spliced or connectors dangling.Speed density systems have check engine lights, and the diagnostic plug for scan tool is up front passenger side. Every mustang from 83 on with an o2 sensor has a computer and check engine light. Are you sure you don't just have a burnt out or missing bulb for your cel? You can buy a fairly cheap scanner for the EEC 4. I have one I'd like to sell cheap as I have a 2000 ford expy with obd2 system. Send me a pm if interested or to my email Stevelandau81@yahoo.com.
Sent from my iPhone using Tapatalk
Finally! Found the problem, or another problem. I had continuity through everything to the cluster and the light bulb worked. Followed the circuit board looking plastic sheet on back of instrument cluster and found this (see pic) the broken circuit on right is connected to almost all the bulbs, mostly idiot lights. They make copper tape to fix this?Well theirs your problem, you've got a Frankenstine car pieced together. You may have to rewire everything to get all your sensors and computer talking to each other. Other than that you could try circumventing around it all, but come smog time your going to be s.o.l.!
Sent from my iPhone using Tapatalk
Finally! Found the problem, or another problem. I had continuity through everything to the cluster and the light bulb worked. Followed the circuit board looking plastic sheet on back of instrument cluster and found this (see pic) the broken circuit on right is connected to almost all the bulbs, mostly idiot lights. They make copper tape to fix this?
Where do I add a wire from and to? Not the jumper wire on cluster, for the cal86-88 speed density 5.0 mustangs do not have a functioning check engine light. The bulb is there, but it's not wired in. The 2.3L cars DID have a functioning CEL those years.
First 5.0 to get a working cel was the 88 Cali cars with mass air. Mass air swapped 87-88 cars won't have the CEL automatically work. You still need to add another wire first
The diagnostic test port is rear drivers side of the engine bay, next to the brake booster.
And yes, this is a 12 year old thread
Sent from my iPhone using Tapatalk
Is just jump a wire under the grounding tabs of the bulb sockets
Also, that appears to be an 87-89 Guage cluster.
Sent from my iPhone using Tapatalk
Where do I add a wire from and to? Not the jumper wire on cluster, for the cal
Then I'm done. The light works now with the jumper even though I bought the scan tool. Thought it worked like a new car with all the sensors. Thanks to everyone for the help.You need mass air first. Your still running and SD harness and computer.
Honestly, it's not really worth it. Of the possible 90 codes, only 13 trip the cel. It's not like modern cars.
Buy and innova 3145 for $25 and just run the codes every now and then.
Sent from my iPhone using Tapatalk
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?