ive searched around and found that many people have check engine light problems at start or at idle.
cant really find what im looking for because its just weird.
my check engine light comes on SOMETIMES when in the middle of driving(not even pushing the car) then i stop to check everything and it seems fine. right when i turn on the car again the light goes away.
its basically like a heat sensor but its not..when the cars running warm and fine it goes on.
but other than that the cars perfectly fine
anyone know whats going on?
i cant even check for a code since the light doesnt go on unless the car is on and has been driven for a while.

 

I had the same problem...it's probably the Air Intake Thermosensor ($45) under the UIM. Does it run a bit rich when the light comes on?

 

The ECU stores the codes. Put the jumper wire in the diagnostic connector and read the codes - it will tell you what it found.

Dale

 

^^ what he said

 

cool
thanks guy
im gonna try what dale said...and if it doesnt show anything ill just change the thermosensor
right now i cant do anything...need to swap in my new battery

 

there are an awful lot of sensors to just start randomly replacing them... see what the code is. when the light comes on pop the hood stab in a paper clip and see what it says

 

Just a note.. when you disconnect the battery you'll clear your codes and you'll need to drive the car again untill the cel comes on to flag the code again.

 

man, i love obd2 cars

 

Ya except when some one hits your car just after a bit of spirted driving and your insurance company denies your claim becouse of what was down loaded off the obd2........ Oh crud I gotta go,, there's a black helocopter flying over my house.

 

When you put your new battery in chances are you'll reset or lose your codes. You'll have to drive the car again till you get the CE light and then read the code/codes Jack

 

soory for not reading far enough down the post LOL

 

HAHHAHAHA....gm has the datalogging junk that's downladable through onstar.

*****

 

yeah mine does the same too. Mostly while driving on Freeway, or at a cruising speed, then C.E.L. comes on...
Pull a code 15. O2 Sensor.
Replaced that, but C.E.L still comes on. So I'm guessing it's the wiring on my a/f gauge that I wired it.
Prob. a short in wire?? I don't know. Just don't have the time to check it up yet...

 

yeah thats exactly what i have and what ive thought since it went on
i mean theres no reason why it would give me the CE light out of nowhere unless somethings lose after being heated up or o2 sensor thats just crapping out
ill check it out asap
im currently having the time of my life cleaning battery fluid off the bottom of the battery tray...

 

sorry to hear that..mine does the same thing...

 

well its all good
nothing severe..lets just hope nothing else comes along

 

how the hell do the codes get displayed..? or how do get them..and what pins do u jumper to get them. i read bout some iam assuming tones. sed 1long and 6short....

 

yeah i need that to be carified also
although im not going to check anytime soon since i have no battery
but its good to know ahead of time

 

From: "Nowhere Man" (rx7@otf.cyber-west.com)

You can actually check the code yourself following these sneaky instructions. I list the meaning of the codes after these instructions.

First, at the diagnostic plug, located near the battery under the hood, short the TEN connector to a ground connector.

Once connected, turn ignition to ON.

First digit of service code (tens position)=number of times the check engine light illuminates for 1.2 seconds.

Second digit of service code (ones position)=number of times the check engine light illuminates for 0.4 seconds.



Delay between codes is 4.0 seconds.

In other words, one long flash, followed by 5 short flashes means a code 15. This will repeat again after 4 seconds (or, if your car is really screwed up, a different code will follow).

The ECU will cycle through all the service codes. After reach the last service code the ECU will go back to the first service code and repeat the cycle until the ignition is turned OFF.

Disconnect the negative battery cable. Wait at least 20 seconds then depress the brake pedal.

Reconnect the negative battery cable. Codes should be cleared. If not, a problem may still exist.

The codes are:

02 - Crank angle sensor (NE signal)
03 - Crank angle sensor (G signal)
05 - Knock sensor
06 - Speedometer sensor
09 - Water thermosensor
11 - Intake air themosensor
12 - Throttle sensor (full range)
13 - Pressure sensor
14 - Atmospheric pressure sensor (in ECU)
15 - Oxygen sensor
16 - EGR valve (California only)
17 - Feedback system
18 - Throttle sensor (narrow range)
20 - Metering oil pump position sensor
23 - Fuel thermosensor
25 - Solenoid valve (pressure regulator control)
26 - Metering oil pump (stepping motor)
27 - Metering oil pump
28 - Solenoid valve (EGR)
30 - Solenoid valve (split air bypass)
32 - Solenoid valve (relief 1)
32 - Solenoid valve (switching)
33 - Solenoid valve (port air bypass)
34 - Solenoid valve (idle speed control)
37 - Metering oil pump
38 - Solenoid valve (accelerated warm up system)
39 - Solenoid valve (relief 2)
40 - Solenoid valve (purge control)
42 - Solenoid valve (turbo precontrol)
43 - Solenoid valve (wastegate control)
44 - Solenoid valve (turbo control)
45 - Solenoid valve (charge control)
46 - Solenoid valve (charge relief)
50 - Solenoid valve (double throttle control)
51 - Fuel pump relay
54 - Air pump relay
71 - Injector (front secondary)
73 - Injector (rear secondary)
76 - Slip lock up off signal
77 - Torque reduced signal

 

I've had similar symptoms in the past. Ended up i didn't have a good/solid connection for the o2 sensor