egp320i

he claims that a cold start injector helps the engine start up even if its 80f out, I say no, its much lower then that, say under 50f. I did not see any mention in the bentley for this (8V).
I am pretty sure the cold start runs off a sensor that is attached to the block so if the sensor is faulty, it could cause enrichment?
so who is right?

tpierce

the thing is that you need to see what temp the sensor switch is. It still may use the injector when it is 80F outside, but wouldn't really need it. If the switch is set for 60F for instance, then it wouldn't be used when it's 80F out. Remember, that no matter what outside temp, a "cold" engine (one at or near ambient temp) runs rich when first started.

egp320i

its the sensor that directs the injector on what to do. this sensor on the 4cyl should be the one that is right in front threaded into the block by the engine hoist eye.

YucatanAudi

<center><img src="http://pictureposter.audiworld.com/60004/cold_start_injector_42198247.jpg"></center><p>First off, from the graph, you can see that, even at 80-100 F, the cold start injector operates for about 1 second or so.

<b>DESCRIPTION &amp; OPERATION</b>

The cold start valve, located on the intake manifold, is used to provide fuel enrichment for easy starting, even at very low ambient temperatures. The valve is controlled by the <b>fuel control ECU</b> and operates for varying periods of time, depending upon the signal from the <b>coolant temperature sensor</b>. Fuel is supplied to the valve at system pressure from a port on the fuel distributor. At very low temperatures, the valve provides additional fuel for as long as 10 seconds after initial cranking begins. At warmer temperatures, the duration is reduced. For more information, refer to COMPUTERIZED ENGINE CONTROLS .

<b>CHECKING NORMAL COLD START OPERATION</b>
1. With the engine cold (coolant temperature below approx. 68°F/20°C), disable ignition coil by disconnecting electrical connector from power output stage. If engine is already warm, remove coolant temperature sensor and immerse sensor tip in ice water until sensor is sufficiently cooled, or disconnect sensor and bridge terminals of sensor harness connector with a 1/4 watt 5K ohm resistor to simulate approx. 32°F/0°C.

2. Remove cold start valve from intake manifold, leaving fuel hose and electrical connector attached, and place valve in suitable container to catch fuel.

3. Turn ignition switch to "start" position and crank engine for 10 seconds while observing spray from cold start valve.

o Cold start valve should spray a uniform cone shaped mist of fuel for the period of time shown in the diagram, depending on the temperature of the coolant temperature sensor (or if 5K resistor is used in place of the temp sensor, valve should spray for approx. 3 seconds).

4. When valve stops spraying, dry off tip, disconnect electrical connector, crank engine for 10 seconds to operate the fuel pump and check for fuel leakage. Tip of cold start valve should remain dry. If not, replace valve.

If valve did not spray, energize valve manually by momentarily applying 12V and ground using jumper wires. Valve should spray fuel while energized. If not, replace cold start valve.

WARNING: Fire hazard! Use appropriate connectors and long jumper wires so as not to create any sparks near the valve while testing. The mist of fuel can ignite very easily.

NOTE: If valve operates when energized using jumper wires, but did not operate while cranking engine, there is a problem in the electrical wiring or the ECU. Refer to COMPUTERIZED ENGINE CONTROLS .

egp320i

I am going to pull it and check to see if it has flow. My temp sensor was just replaced so I am positive its not that, but the injector could be clogged or broke, although I have never heard of an cold start injector going bad