Two paths suggested.


1. Running on five injectors and the mixture, fuel/air is close enough to rune. Adding # 6 and the fuel/air mixture is too rich!!


Suspects: Cold start functions in play when unneeded.


Carl

 

The regulator can fail in two ways

- Leaking. The usual test is to remove the vacuum hose. Any sign of raw gas and you know the regulator is kaput. Not unusual. Causes rich running or outright flooding, depending on severity of the leak

- Incorrect fuel pressure. The only test is to use a fuel pressure gauge. Excessive pressure can certainly cause big problems (over fueling/flooding) and seems to be a more common failure mode that too little pressure.

Cheers
DD

 

Ok Carl could I disconnect the cold start injector and see if that fixes it? And Doug when I disconnect the vacuum line to the regulator there is no fuel. I can try hooking up a PSI gauge what should the pressure be? When I hear back I will give it a try. Thanks ..Jerry

 

Use the hose to the cold start injector to hook up your pressure gauge. You're looking for about 36 psi

Cheers
DD

 

OK will do Thanks....Jerry

 

OK Doug & Carl I left the cold start injector plug in and disconnected the fuel line to it and hook up a pressure gauge(not a good one all of my fuel gauges go to 10psi so used a gauge from my paint gun) and the pressure was 38 or 39 psi. But the car started and ran with the cold start injector disconnected, it idled a little lower but ran. What now? Thanks ..Jerry

 

Sure does look like the cold start injector is in play when not needed.


Research it's function/mal function and fixes.


I suspect a simplistic find. Stuck open !!!


In your clime, do you need mixture enrichment to start ??


Off to lunch. Cyber exercise has exhausted me.


Carl

 

OK have a good lunch. Thanks Jerry

 

Ran well, or just so-so?

Pressure a tad high but my gut says not enough to cause a problem.

I'd get a good used cold start injector. "Everyday XJ" is a good source for used parts.

Cheers
DD

 

Doug I am not sure it is the cold start injector. I took it out checked to see if had the right resistance and it did, pulsed it with 12 volts and it open and close fine, I then spray it with carb cleaner while pulsing. It worked fine as best as I could tell. I put it back in the car hooked it up and the car would not start. I then unplug the injector and tried again and it would not start either. If it was the cold start injector I would think the car would start with it unplugged. So I don't know...Jerry

 

Update no. 50....I had the idea from all the other test that it seemed like it was not getting enough air. So I disconnected the flexible fitting from the airflow meter on the firewall side so it would get plenty of air. Well the first crank and it started it idled high ad then low and not normal. I put the fitting back on and the engine died. I tried it again and it started but erratic. It also look like black some came out the exhaust for a little while. Now I am wondering if he ECU could be bad giving me all of these different symptoms. Any ideas or a way to heck the ECU...? Thanks Jerry

 

Jerry:


Back to the cold start injector. You got it to run somewhat decently at one time with the CSI disconnected.


The CSI seems to function. You cleaned and bench tested it.


But, the run/not run is inconsistent.


So:


1. The CSI injected unneeded fuel, and even if disconnected, the engine was flooded and would not fire. Repeat that situation, but open the throttle to clear the flood and crank.


2. Yup the CSI works. But not when needed or when unneeded.
I don't know what commands it to spray fuel or not spray. I suggest
that be investigated


Doug probably has the answer to that.


Keep plugging, you are close...


Carl

 

I tried it with the CSI was unplugged and the bench test told me that if there is no power the injector will not spray, so if it is the CSI it should run with the CSI unplugged???? Thanks for your help...Jerry

 

The CSI gets voltage from the starter circuit and is grounded by the 'Thermotime' switch at the very front of the water rail. It should operate only when the engine is cold and the starter is engaged.

In warmish climates you could leave it disconnected and might not even notice any difference in cold starting.

Sometimes they get stuck and drip fuel but I think that possibility has already been checked.

Cheers
DD

 

Does anyone thin it might be he ECU????( I saw two on Ebay 1 for $40 and the other for $70. Thanks....Jerry

 

1. It is warm your way at this time. So, leave the CSI completely isolated from + or -. Let the engine rest. Crank it. If it runs somewhat decently, you have it. I am sure, I hope, that your efforts have not included leaving the opening open. Naah, apologies...


2. In the norun scenario and sans CSI, for fun, check for spark.


3. IMHO, the ECU is along shot. And howsoever cheap, who is to say that it is good???


4. Should you choose that option, use a trusted vendor. If it were
me, It would be David Boger. Tested in some manner.


Keep plugging.


Carl

 

OK Carl it is 90 plus degrees here, the engine is cool and I unplugged the CSI and cranked it, it stumbled a couple of time but never would start . Not the CSI????? I really kind o loss now? Thanks for your help..Jerry

 

My last attempt before I leave tomorrow for vacation. I did something I suspected. I loosen the CSI and had it unplugged to let air in(it could have been anyone of the injectors). So the I started it and it ran. It ran poorly but ran. It would only idle when I tried to accelerate it would want to die, and it was smoky. I am still suspecting the ECU is not giving the right amount of air and fuel?

 

The ECUs seldom give trouble....but 'seldom' is not the same as 'never'. Yes, it is a possible culprit. As is the AFM. I don't know of any DIY checks to confirm. Diagnosis of them is by replacement with a 'known good' unit.

Cheers
DD

 

Ok Doug thanks for the help....Jerry