Brian'sIROC

My car is running rich and won't go into closed loop. I suspect the cold start injector of causing this problem. If it is stuck open will unplugging it keep it from dumping gas in my motor? Is there any other way of troubleshooting the CSI?

Morley

If it is stuck open, then unplugging it won't do anything. If it is getting a constant signal to pulse, then unplugging it will will help diagnose that.

The only reliable way to test the cold start valve, that I know of, is to pull it out of the runner while leaving it hooked to the fuel rail and turn the key on, look for any leakage from the injector tip (put something under the csi to catch any gas). If you could find a suitable rubber plug to stick in the runner hole, you could concieveably start the car with the injector out and see if it operates while the engine is running.

Bort62

Or just Remove the system all together and get a Copy of the $6e Code w/ the Cold Start Tables

Jza

Yes, unplugging will keep it from being fired by the CS switch. But if the injector itself leaks, the rail pressure will still force some fuel into your intake.

While the engine has been running for at least 8 seconds, test for continuity across the CS switch terminals. If it has continuity, then the switch has shorted or it's heater element isn't working anymore. Replace the switch.

But I don't believe that's the cause of your problem, although you've given admittedly very little information to go on. Not going into closed loop is more likely to be the cause of running rich, rather than vice versa: running rich preventing closed loop operation. In that case, the biggest cause of not going into closed loop would be the CTS.

Removing the CSI isn't going to magically cure anything.

Brian'sIROC

Yes, It is running very rich. The O2 sensor is brand new as well as the injectors. This problem has stumped me for two months now. You say it may be the coolent temp sensor? The scanner is reading the coolant temp, so wouldn't that mean that it's OK? I don't have a code for that, but then again the car is very rich, and not giving any codes whatsoever.

Bort62

Just Goin out on a Limb here.. but You didnt put bigger injectors in it did you ?

Brian'sIROC

Nope, Stock flow (19#) Accel units

Bort62

Okay, So your Running pig Rich and Won't go into Closed Loop.

Coolant temperature is reporting as normal.

I don't see how the CSI, even if faulty, would cause you to remain in Open Loop.

Are you sure you arent in Limp Home ? Is the SES light working ?

The 02 Sensor isnt an issue, as it is not used in Open Loop,

Do you have the Vac Line connected to the Fuel presure regulator ?

Brian'sIROC

Yes the SES does function. It comes on when I turn on the key. It also gives a code 12. The FPR vacuum line is attached.

Bort62

Well Unfortunately im racking my brain for the Closed Loop Conditions, and they just arent coming to me.

Try a search. The Coolant temp is the obvious one, but if that is not the case then your gonna have to look a little harder, haha.

Sounds like a real PITA.

Just to cover all bases, did it ever run okay with the SLP PROM ?

Brian'sIROC

Ahh, you remembered the SLP prom. Yes, It ran fine before with the SLP prom. Right now the stock prom is in it though. Since the scanner reads coolant temp, that rules out the CTS right? I still think the CSI may be leaking, everything else has been checked or replaced. What about a bad ECM? Could that be an issue?

Bort62

Yeah, if your getting a Coolant temp on your scanner other than -41* C, then it is probrably working.

Lets start at the beginning. How do you know you are running Rich ?

As I see it the primary indication of a problem here is being stuck in Open Loop. This can be caused by a finite number of things, the primary cause is Low CTS value.

But there are other conditions, wich you should discover and investigate.

I imagine once you find the reason for your being in Open Loop, the Richness will Go away.

Brian'sIROC

My scanner is telling me it's rich and in open loop.(my nose also) It used to switch back and forth from rich to lean in closed loop. A few times when I've had the scanner hooked up it went into closed loop and the idle started surging, then it went open again.

Morley

Personally, just eliminate the ecm, I'd see about getting one from someone here or maybe e bay and swap them out (you should have a spare ecm anyway, just in case). Or if you know someone with the same ecm, you could borrow it and see what it does in your car.
I agree with the others here, a leaking or even fully open csi won't keep the car in open loop.
Three things must happen for closed loop to be entered; Coolant temp greater than 150ish ( not positive on this number)
The O2 sensor must start switching above and below 450mv
And the last a specified amount of time from start up needs to elapse.
I don't know where the timing circut is for elapsed time, it might be in the prom or possibly in the ECM. Check your scanner and see if it is reporting run time for the engine. You said the scanner is reporting the coolant temp so we can rule that out. Next is the O2 sensor, I know you said you just replaced it but we all know about bad parts from the vendor.

Bort62

I don't know what part of Nor-Cal your in, But I can get my hands on a known good working 165, And Im in Morgan Hill, South of San Jose a Tad.