Flickering checke engine light?!?!?

[ROJO]

Flickering check engine light?!?!?

I just purchased a 1997 Ford Ranger with 102000 miles on it. The vehicle is in excellent shape and is running great. The only real problem that I am having is that the check engine light is on and it will flicker constantly while I am driving. It will also just turn off at times too. I took the Ranger to Autozone and had them check the codes, but it was not throwing any. If anyone has suggestions as to what I can do to fix this issue that would be great.

Thanks in advance!

Ken

 

[Ranger Sport Honduras]

maybe its a aulty check light on the dash.
theres a how-to for taking out the gauges cluster on the tech library.

 

[necessaryevil]

you my friend have a short some where, the cel is a negative switched circuit, so nothing is really going on with the truck, you just have a wire rubbing on metal, i would first pull the cluster and trace the cel circuit and test it with a ohm meter if its not there then i would start inspecting the dash harness with a flashlight for any kind of rub marks.

 

[ROJO]

Thanks for the suggestions. I will look into them when I am off of work.

 

[Earl43P]

Flashing CEL means a serious engine misfire.

I wouldn't trust an AutoZone clerk's diagnosis.

 

[GoodOld85BlueBalls]

Just pull the bulb out of the lamp.

 

[adsm08]

Flashing CEL means a serious engine misfire.

I wouldn't trust an AutoZone clerk's diagnosis.

While that was my first thought too, a class A misfire isn't a condition that usually leads to the engine being described as "Running Fine". And even the most incompetent AZer would probably have trouble missing that one with a code reader.

Also, the description of what the light actually does sounds more like a ground-side short than a class A miss.

 

[necessaryevil]

even with a misfire the eeprom would store a code like 212 for something like 50 key-ons, ive never seen an obdII just "flash" the cel while driving, if it comes on it stays on until key-off

 

[adsm08]

even with a misfire the eeprom would store a code like 212 for something like 50 key-ons, ive never seen an obdII just "flash" the cel while driving, if it comes on it stays on until key-off

An OBDII system would store a P030* code until the misfire issue had been resolved. And the flashing CEL for a severe misfire is something that EEC-IV didn't have, it's specific to OBDII.

 

[necessaryevil]

and even if it is non recurring it would still store the code for a misfire under the PID system and even tell you how long since the code has been cleared. heres some further reading http://en.wikipedia.org/wiki/OBD-II_PIDs

 

[ROJO]

Problem solved! Thanks for the advice that was provided in this thread. I was able to trace it to a small connecter on the back of the engine block that was rubbing against the ground strap. A little electricians tape and the flickering light is gone. Time to go get my safety and emissions done!

 

[BRUTUS_T_HOG]

even with a misfire the eeprom would store a code like 212 for something like 50 key-ons, ive never seen an obdII just "flash" the cel while driving, if it comes on it stays on until key-off

yep, happens all the time. if its a catalyst damaging condition then the light will flash.

want to see it in action? unplug a spark plug wire on an OBD2 vehicle.. light should start flashing in less than a minute

 

[snomaker321]

yep, happens all the time. if its a catalyst damaging condition then the light will flash.

want to see it in action? unplug a spark plug wire on an OBD2 vehicle.. light should start flashing in less than a minute

wanna see it really in action? just look at the ranger in my driveway(the '96) Not too bad at idle but the things like a bucking bronco when you put in in gear and the rpms drop, cel never stops flashing

ROJO, just curious but do they not let you check the codes yourself there? I usually go to advance auto and i just give them my license and they hand me the obdII scanner.