Couple of ECU codes

[kota2240]

my idle fluctuates from 500-1200 consistently and sometimes dies. I noticed spark plug two and four were convered in fuel. I checked my ecu for codes and got 13, 21,43. These are engine temp, ignition, and tps. I tried changing the engine temp from my s13 KA still no luck and i changed the tps from the same car and still no luck.

Ignition, I looked at the FSM and it said check connection from ecu to the power transistor. All my coilpacks are firing?? So what the **** does it mean by ignition.

Do these parts have to be from a CA18?

Also whats the proper way to set the TPS, im having trouble understanding the FSM.

I wasted all day ****ing day with this ****, please help
Modified by kota2240 at 8:01 PM 4/23/2006

[kota2240]

Im sorry its code 43 for the throttle sensor, with this unhooked it still runs crappy at idle

[damesta]

Check your timing and compression.

[kota2240]

Its difficult to check my timing since its bouncing around due to my idle fluctuations, but its around 15. Im getting 20hg from my boost gauge at idle, so does that mean my fpr is okay and i have no vacuum leaks? I purchased a new engine temp sensor from a pulsar CA18, still idles the same.

[kota2240]

here is an update, please help me out if you can. The idle sounds better now after i installed a filter on my maf. I never expected that. When i rev the motor up it sounds like its misfiring and bogging. I checked the faq, the only thing different from my setup is the aac is hooked into my cold pipe. My compressoin is like 140 on all four. I did it while the motor was cold.

[Elmer]

Got exacly the same issue with RPMs, didnt checked ECU codes thoe (will do). Anyone can help?

[compactfean]

Lets start with code 21. I personally hate this f*** code!!! I took me a year to diagnose! On srs' in the wiring that fits from chassis to engine there are 2 blue/red striped wires. One is to power the coil packs, one is to power the igniter chip. If the small wire spent have power when running OR WHEN CRANKING, I got code 21. Car started up and ran fan but I still got code 21.
Code 43 check the plug for power, 5v should exist. Check plug for ground, continuity should exist. Then set tps to .45 volts and slowly open throttle by hand. Voltage should slowly and smoothly sweap to 4.xx volts.
The temp sensor 5v should exist on one wire, continuity to ecu temperature input should exist from plug to ecu. Let us know how.it goes.

[Elmer]

ECU showed onlu code 34 which is Knock sensor. A little googling and it quite fits. Im not sure if it is making problems with RPMs but I've tried to set timing but the marks are like to show everytime in a different place (now way off to the right). Can the knock sensor does all of those problems? Jumping RPMs, timing issue?

Please tell me that I can change knock sensor without taking off intake manifold! I've just mounted it back!

[Elmer]

Actually Im pretty sure now it is because knock sensor, all symptoms match - jumping rpm's, too much fuel, problems with ignition timing and I got error 34 on ecu - knock sensor send signal to ECU which gives more fuel and retards timing for safety. The possibilities are:
1. broken knock sensor
2. problem with knock sensor circuit (maybe wire shield etc)
3. ecu
4. knocks in engine (but as I read - error 34 means problems with sensor or circuit not that there is a knocking - and I got problems on idle - there should'nt be any knocking on idle or if it is full throttle ride should damage engine right away).

The problem is knocking sensor is quite dificult to dismount - its under intake manifold. There is a way to trick the ECU - you need to connect ecu pin to the ground and get a 1M ohm resistor on that but if sensor is ok and the engine is knocking it can cause damage :/ Im not sure what to do. Im thinking about making a headphones connected to engine block and listen if there is knocking.

[float_6969]

Just to make sure, you do know that due to the differences in the harnesses, the knock sensor has no way of connecting to the ECU and you have to run a wire from the sensor, to the ECU when you swap a CA18 into any chassis?