CA20E Rough Idle/ No Start/ Code 41

[weitrhino]

They should be correct. In fact they may well be better than the factory connectors. By the look of them the metal C clip can easily be retracted for disconnect.

[dustins12]

UPDATE:

Just ordered some new sensor clips for the S12, waiting for those to come in as well as my new head bolts, head gasket and some other stuff. Then I'll be putting all of this stuff on. Hopefully all of this detailed clean-up will fix my issue, even if my efforts are a little excessive for this problem, I'm hoping for some results.

[dustins12]

UPDATE

So it's definitely been awhile since I've updated this. The S12 has been sitting for awhile, and I recently dived back into it again. So, I'll update where I'm at with everything.

- Did not replace head gasket because it wasn't necessary. I had 165psi on all cylinders.
- Replaced all injector clips and insulators.
- Replaced temp. sensor and clip for it.
- Replaced all vacuum lines with new lines.
- Has new timing belt and water pump. I have to dial in ignition timing still.

I need to replace my intake pipe and couplers. Upon closer inspection I realized that the clamps were doing absolutely nothing because the 80's rubber couplings are hard as rock, and severely cracked allowing unmetered air in. I feel like this may be a big part in why it's running very poorly still.

So yeah, the car will actually start up and "run", kind of. It fires up every time now. It goes back and forth on needing help idling, and other times it idles perfectly by itself. Again, I need to dial in ignition timing, and replace intake pipe and couplers. Also, gonna properly check out the IAC and air regulator again. Can't remember if I cleaned those out or not.

[cunninac]

I'm running into the same problem with my idle after I replaced the valve seals. Once she warms up it seems to idle fine, but really low on power. Thanks for updating this so thoroughly. I'll get after mine running through the same steps that have been recommended to you.

Cheers

[dustins12]

Okay, so I did a little more work on the car last night. Went and took the piece on the back of the intake manifold off, cleaned it all out (there really wasn't too much build up in there). Put it back on, car still ran the same. I'll reiterate, the car starts up every time now. After letting it sit overnight, it'll run fine by itself for a few seconds and then die. After starting up again, it says it's idling at around 600rpm, but it's "skipping" or sounds like it's "bogging" a little.

I unplugged the thing on the back of the intake manifold, didn't make a difference in how it ran at all.

I also checked the ignition timing again, it's spot on.

Can somebody give me more info on the air regulator. What it does? How to check if it's good/bad? And how to bypass it if possible?

[weitrhino]

Now that you have progressed this far, have you cleared the ECU codes and looked to see if anything new has shown up?

[cunninac]

Now that you have progressed this far, have you cleared the ECU codes and looked to see if anything new has shown up?

Since these are not OBD2 how the hell do we check the ECU codes. I guess I'll dive into the FSM and check it out.

[weitrhino]

There's a process and you have to count the LED flashes to get the corresponding code.

[dustins12]

I'll have to check the ECU codes again, although they have never been helpful in the past whatsoever haha!

I also unplugged the TPS to see if it changed anything, and the car ran the exact same whether it was plugged in or not 😧 so, I'm probably gonna run through every sensor I can, check them all and make sure they're working properly. I also wanna go through and check my coils and the distributor (replaced cap and rotor already). Just wanna make sure they're firing properly. When I used the timing light, it was flashing sometimes, and sometimes not. Not sure if it was a problem with the car or iF it was because it's a harbor freight timing light lol may have to see if I can borrow a better quality timing light.

Since these are not OBD2 how the hell do we check the ECU codes. I guess I'll dive into the FSM and check it out

It's really simple actually. On the CA20E, you have to use a small flat head screwdriver, turn this dial one way until it flashes to let you know it's in a certain mode, turn it back and count the flashes like mentioned above. Corresponding number is a certain code. Just like most OBDx cars.

[cunninac]

I'll have to check the ECU codes again, although they have never been helpful in the past whatsoever haha!

I also unplugged the TPS to see if it changed anything, and the car ran the exact same whether it was plugged in or not 😧 so, I'm probably gonna run through every sensor I can, check them all and make sure they're working properly. I also wanna go through and check my coils and the distributor (replaced cap and rotor already). Just wanna make sure they're firing properly. When I used the timing light, it was flashing sometimes, and sometimes not. Not sure if it was a problem with the car or iF it was because it's a harbor freight timing light lol may have to see if I can borrow a better quality timing light.

It's really simple actually. On the CA20E, you have to use a small flat head screwdriver, turn this dial one way until it flashes to let you know it's in a certain mode, turn it back and count the flashes like mentioned above. Corresponding number is a certain code. Just like most OBDx cars.

I followed the instructions here http://club-s12.org/retro4/index.php?topic=7188.0 to check the ECU codes and I received a 44 code... normal operation. Not really sure where to go from here with the rough running and such. I personally replaced all of the vacuum lines throughout the engine bay, some of them were in pretty bad condition.

Anybody have an idea of where to progress?

[dustins12]

Still getting Code 41. Anybody know what voltage is needed at the Air Temp Sensor in the Air Flow Meter. Currently getting 4.8-5.0 volts in the "ON" position.

[weitrhino]

Can somebody give me more info on the air regulator. What it does? How to check if it's good/bad? And how to bypass it if possible?

From the factory manual:

Air regulator gives an air bypass when the engine is cold for the purpose of a fast idle during warm up.

The air regulator is factory set and shouldn't be fooled with. It has a metal film valve inside that is in the open position when the engine temp is cold. As the engine warms current flows to an internal heater which causes the valve to close. It stays closed until the engine cools causing the valve to default back to open.

Unfortunately I haven't found any hard info on AFM output voltage, only a reference to pre-set voltage and that if it is low the computer kicks on the Idle Up Solenoid. (IUS would normally kick on when the A/C is turned on because it presents a larger load to the engine at idle, for example)

[dustins12]

UPDATE!

So, I got the car running and driving and I've also come to the conclusion as to how it was fixed. I believe the problem was a multitude of things including: exposed wiring, faulty sensors and some shady work done by previous owners. The car isn't perfect, but it will be after some minor tweaking.

If anyone has anymore questions about this topic or wants to know anything more in-depth about my diag process, message me directly.

[rednucleus]

Congratulations! Hooray for another mighty CA20 success!!

[kelso840]

We're talking about the success being mighty, right?


Congrats man! Always fun bringing a basket case back to life.