Stumped by my Fuel injection operation , cold idle ????

[Killain]

Continuing along my Fuel Injection journey, I had a problem with my cold idle being so low the engine would stall out. So after reading my FSM, and help from here, I deducted it was the Air Regulator Valve, I was able to find one and that did indeed, raise the cold idle engine speed, but now the 1500 cold idle rpms stay high and only after 20 minutes running does it drop to 1000 rpm's and even then I have to stop and raise the hood to get to the idle screw and lower the idle speed down to 800 rpm's. Now I don't see what else would keep the speed at high idle other than perhaps the coolant temperature sender being bad, I am pretty sure I don't have any vacuum leaks, but the engine didn't seem to have a vacuum leak before I installed the new Ari regulator Valve. But the gauge on the dash doesn't off and it reads normal ? So other than the AGV and or the temp sensor relaying faulty reading to the ECM, what am I missing here ?

Edited June 20, 2022 by Killain

[kickstand80]

The cylinder head temp sensor signal only leans the fuel as the engine warms, it does not change the idle. The only way your car idle changes is if more air gets in. Look for vacuum leaks. Did you purchase a new secondary air valve or find a used one? It may be incorrectly adjusted or sticky. I had to adjust mine. 

 

[Killain]

ah, No I found a rebuilt 'Air Regulator Valve' Which did correct the cold idle engine operation. Before the new Valve, the engine wouldn't idle enough to keep running when the engine was cold and it would stall. But with the new valve it idles very high 1500 rpm's but now it doesn't come down for over a half an hour. Now the Air Regulator Valve isn't adjustable so what you get is all there is ?

[Zed Head]

1 hour ago, Killain said:

with the new valve it idles very high 1500 rpm's but now it doesn't come down for over a half an hour.

This is a sign that there is no electrical power at (edit - actually should say "passing through".  The ground side must be there also to complete the circuit) the AAR plug.

Edited June 20, 2022 by Zed Head

[Killain]

So despite correcting for no cold idle operation, the valve isn't getting correct or any voltage ? Is that circuit protected by a fuse or fuse-able link ?

 

Thank you,

[kickstand80]

Power on with key

Edited June 22, 2022 by kickstand80

[Zed Head]

It's on the same circuit as the fuel pump.  Looks like it grounds through pin 34.  You can test the whole circuit at the ECU connector.  The FSM instructions describe how to use the Start circuit to actuate the fuel pump relay to provide voltage. 

But you could also just disconnect the AAR and test for voltage at the AAR connector with the engine running.  The AAR should get power when the fuel pump does and the fuel pump only gets power when the engine is running.

[cgsheen1]

Check for power and also check the connector for corrosion / oxidation and clean it. It's a Bosch connector just like the injector connectors and can be replaced with a new one if necessary.

[Killain]

Ok Great, on page EF-24 it talks about the Thermotime switch. I never used a multimeter, so I got one and I'm teaching myself about how to use it. I will pull the Air regulator Valve connector and see if 1. it's getting any power and then see if I can measure the voltage. The last big repair job I did was try to repair my marriage, of course she been gone for the last 14 years, so I guess that wasn't very good fix ?

Edited June 20, 2022 by Killain

[kickstand80]

IDK problematic wife / problematic Z? You can always sell the Z and get your money back!

[Zed Head]

1 hour ago, Killain said:

I never used a multimeter, so I got one and I'm teaching myself about how to use it. I will pull the Air regulator Valve connector and see if 1. it's getting any power and then see if I can measure the voltage.

You can also stick a Noid light in the connector and start the engine.  The light should stay on when the engine is running.

[TomoHawk]

It should only have 12V after about 10 seconds, if the thermotime switch is working correctly.  Otherwise, it should have 0 volts when you first turn on the power.  In any case, test it under a load.

Have you downloaded the Fuel Injection Bible, and flowwed the troubleshooting charts?

Edited June 20, 2022 by TomoHawk