check engine light comes on after changing clutch? Options

[st202gt]

94 celica gt...well my engine light came on after we had finished changing my clutch... The speed sensor wire that attach to the transmassion was broken off and had to replace it with a used one that i got at the junk yard...first when i did the wire and disconnected the battery..the speed on the gauge didn't work, but the rpm work... i rewire up again and now it works....but the engine check light comes on as you start up the car... I tired to get rid of it. but it still comes on when you start the car...I think it the wire that is moving around to cause for that to happend or some other thing....I really need help or advice about this...because i need to smog my car in oct.

[Rjb23]

Uhhhh Huhhh?

[Delta_Phoenix]

you can do a diagnostic check of your CEL. check this page for instructions. i forgot exactly where it tells how to do it. you have to use a paper clip or some other piece of metal and bridge 2 of the pins in your diagnostic box under the hood. the site lists the codes and all, so you should be able to figure out what's causing it pretty quickly. i'll look for it and get back to you with a direct link to it.

[Delta_Phoenix]

alright, here you go.

Check your battery voltage (should be greater than 11 volts), turn off all accessories, put your car in neutral, and make sure your car is at operating temperature.
Jump the terminals TE1 and E1of the "Data Link Connector 1" with a jumper wire (a paperclip will do).
Turn the ignition to "On" (but dont start the car)
Read the trouble code by watching the flashes of the check engine light
Sample Trouble Codes: These codes are for a 6th Gen. Celica...They may, however, be similar and/or carry over to other cars.

Code Blink Circuit
n/a 8 flashes normal
12 1, then 2 G, NE signal (#1)
13 1, then 3 G, NE signal (#2)
14
1, then 4 Ignition Signal Circuit
16 1, then 5 A/T Control Signal
21 2, then 1 Oxygen Sensor Signal
22 2, then 2 Engine coolent Temp Sensor Signal
24 2, then 4 Intake Air Temperature Sensor
25 2, then 5 Air/Fuel Ratio Lean Malfunction
26 2, then 6 Air/Fuel Ratio Rich Malfunction
27 2, then 7 Sub-Oxygen Sensor signal
31 3, then 1 MAP sensor
41 4, then 1 Throttle Position Sensor signal
42 4, then 2 Speed Sensor Signal
43 4, then 3 Starter Signal
51 5, then 1 Switch condition signal
52 5, then 2 Knock Sensor
71 7, then 1 EGR System

[lagos]

what you broke is the tranny speed sensor, thats why your speedo didnt work. disconnect the batterie for a few min to let the codes in your ecu clear. then drive around and see if it comes back. if it does, then pull the codes in the method described above and see what the ecu is telling you.

[st202gt]

well i fixed that problem with my speed sensor...did the te1 and e1 test on the car and came out code 52...is the knock sensor...it might be lose or doesn't work no more...i will need to replace it..do u guy know how much will it cost?

[Delta_Phoenix]

Niehoff Ignition WA1766
Detonation (Knock) Sensor:
3 Month Limited Warranty
$174.99

Niehoff Ignition WA1730
Detonation (Knock) Sensor: w/ Nippondenso
$142.99

Well, there's the damage. Considerable damage for a sensor

That's from Advance Auto Parts. You may be able to find it cheaper elsewhere.

[lagos]

"knock sensor" could also mean that the sensor detected a knock in the motor.