Idle problem and missing CEL indicator
09-13-2011, 05:36 AM
#1
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Vehicle: 1997 hyundai coupe
Idle problem and missing CEL indicator
hi all,
i'm encountering a few problems with my 97 tib.. first, i have an idling problem. i've used the search function and couldn't find a thread with a similar problem. basically, i observed that the car starts to idle erratically while cruising (ie: having the car run on inertia after going down a ramp, bridge, downhill slope etc.) the RPM needle jumps from 1000 to 2500 around 3 - 5 times until i have to push the throttle down to stabilize the car's acceleration. after pushing on the throttle, the car runs fine. the erratic increase in RPM also sometimes happens when i'm on neutral / park. again, the idling is solved by pressing on the throttle. any ideas? It's an 2.0l Autotragic btw.
Lastly, this seems really stupid but i could not seem to find the Check Engine Light in my tib. i looked at the manual and took note of where it should be. i used a flashlight to somehow see the outline of the Check Engine Light but it really isn't there. also, shouldn't the CEL illuminate while starting the car (similar to how all the other indicators light up before starting).
any ideas? thanks in advance guys
i'm encountering a few problems with my 97 tib.. first, i have an idling problem. i've used the search function and couldn't find a thread with a similar problem. basically, i observed that the car starts to idle erratically while cruising (ie: having the car run on inertia after going down a ramp, bridge, downhill slope etc.) the RPM needle jumps from 1000 to 2500 around 3 - 5 times until i have to push the throttle down to stabilize the car's acceleration. after pushing on the throttle, the car runs fine. the erratic increase in RPM also sometimes happens when i'm on neutral / park. again, the idling is solved by pressing on the throttle. any ideas? It's an 2.0l Autotragic btw.
Lastly, this seems really stupid but i could not seem to find the Check Engine Light in my tib. i looked at the manual and took note of where it should be. i used a flashlight to somehow see the outline of the Check Engine Light but it really isn't there. also, shouldn't the CEL illuminate while starting the car (similar to how all the other indicators light up before starting).
any ideas? thanks in advance guys
09-13-2011, 07:47 AM
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TPS is a very common sensor that goes bad on RD's and presents the erratic idle and acceleration at times
Check the sensor itself and look for the name "dae sung" on the front, dead give away. The "good" ones are made by
"kefico" although I've seen them fail as well.
When all else fails check the voltage sweep on the signal wire while moving the butterfly. .5v-4.5v sweep closed to WOT.
Regarding the CEL it should light up with the key on, more than likely the bulb blew out, which is easy to replace once you get to the instrument cluster. A bad TPS normally does NOT throw a code.
Check the sensor itself and look for the name "dae sung" on the front, dead give away. The "good" ones are made by
"kefico" although I've seen them fail as well.
When all else fails check the voltage sweep on the signal wire while moving the butterfly. .5v-4.5v sweep closed to WOT.
Regarding the CEL it should light up with the key on, more than likely the bulb blew out, which is easy to replace once you get to the instrument cluster. A bad TPS normally does NOT throw a code.
09-13-2011, 09:13 PM
#4
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^ what he said, except to add that TPS is Throttle Position Sensor . . . when it has a bad spot, the car thinks you are fooling around on the gas pedal when you are not.
09-19-2011, 03:38 AM
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took a look at my TPS and i have the Kefico brand. wiggled it a bit and everything seems to be back to normal for now. i'll be looking for a replacement within the week just to be safe. also, how do you clean sensors? any general cleaning term for the product?
CEL light, still couldn't find it but i'll check again within the week as per TibbyTurbo's advice. i never tried looking at the top most right of the dash. i've used my flashlight to see if i can make out any of the "masks" or patterns the unlit CEL makes but no joy as of now.
CEL light, still couldn't find it but i'll check again within the week as per TibbyTurbo's advice. i never tried looking at the top most right of the dash. i've used my flashlight to see if i can make out any of the "masks" or patterns the unlit CEL makes but no joy as of now.