CEL Question

[trailbikerider]

The CEL on my '94 keeps coming on randomly, and seeing as how I don't have access to an OBD I scanner, I thought maybe somebody on here could lend some words.

Every once in a while the truck will throw the light, and for some odd reason, the Tachometer reads half of the RPMs the truck is actually turning, and it will start running rough, especially at an idle.

Then most of the time it'll run fine. I've been told it might be the Camshaft Position Sensor?

Thanks in advance.

 

[Mazda]

Take it to Autozone and they will scan it for you. Then let us know what they are.

 

[DJ2.3]

Look in the Tech section under eec-IV diagnotics, that will tell you how to retrieve your codes.... My guess is that it is a coil pack, if not that then the ignition control module. I had the same problem on my 92 a few months ago. I forget what code it gave but i replaced both coil packs with some used ones i had laying around and the code hasn't returned.

 

[dmassey]

94 is OBD 1 or at least mine is. Mine did exactly as your saying except for the tach (I don't have one anyhow) and the code was pointing at a coil pack. I tried both coil packs and no difference. Took the coil pack back to Advance Auto. As it turned out it was the DIS module. Went to the junk yard and picked one up for $35. Put that on and have had not further problem with it other than the pesky DPFE sensor which draws condensation like crazy. Hope this helps.
Danny

 

[adsm08]

Cam sensor has nothing to do with the tach. Crank sensor gives tach signal through the DIS module.

 

[trailbikerider]

The problem is that it doesn't come on until after the truck is warmed up a little bit, and it seems to do it more the colder the ambient outside temperature gets. Thus getting a reading on a scanner will be difficult.

 

[adsm08]

It will still have stored the code in memory.

 

[trailbikerider]

I'll see what I can come up with. I have a buddy with an OBD I & II scanner so I'll see if I can borrow that from him..

 

[alwaysFlOoReD]

I'm pretty sure that you can retrieve codes with a multi-meter. I'm sure I saw the how-to on this site somewhere.

Richard