Simple test of the return fuel line

Can't remember the last time I worked on a 3.8 NA .. and can't find any information regarding the stock injector size in the FSM.

The gen 1 SC uses 30# injectors at 1.5x volumetric efficiency - this is where I believe 19# injectors on a NA at minimum. Except you pulled 24# injectors from a similar year / model engine makes me second guess that theory.

As for setting the codes, the OBD1 is just a comprehensive component monitor - in other words, it only checks the sensor resistance to be within a certain range. The codes may also indicate that the sensors are not switching voltage. That said .. the only way to know what the Oxygen sensors are reading and what the engine is actually putting into the exhaust would require an oscilloscope or graphing multimeter, and a 5 gas analyzer. I suppose at a minimum you could use a regular volt meter just to see if the Oxygen sensors are producing any voltage - it should be somewhere in the 2.5V range.

The oxygen sensors are not used by the PCM for adjusting fuel mixture until the engine conditions are met to go into closed loop operation - in other words, you won't get these codes unless the PCM is seeing what it needs ( coolant temp / throttle body, etc ).

Remember the Oxygen sensors do not actually read fuel content in the exhaust - they produce voltage when Oxygen is not present. I won't get too deep into this, its just speculation at this point, because I believe that the root of your problem may be that you threw away the original injectors.
 
Honestly, looking at several "other" injectors that are supposed to work with a 94 3.8l range from 14 to 30 or more.
 
Only the Gen 1 SC (89-93) used 30# and the Gen 2 (94/95) used 36#. You will not find these on any factory NA 3.8.

Correct me if I am wrong - but I think the 24# were used on the Splitport 3.8s .. so that would leave the 19# and 14# .. the 14# would be more along the lines of a pre-89 3.8L.
 
dDUBb said:
Only the Gen 1 SC (89-93) used 30# and the Gen 2 (94/95) used 36#. You will not find these on any factory NA 3.8.

Correct me if I am wrong - but I think the 24# were used on the Splitport 3.8s .. so that would leave the 19# and 14# .. the 14# would be more along the lines of a pre-89 3.8L.
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What I was trying to convey is that in my research, if you look up "1994 ford 3.8l injector" you get a host of injectors that are supposed to work. The ones mentioned above were from Summit for this engine. This is why I am looking into what injector was supposed to be on this car. From all the research I did, the injectors I pulled from the junkyard 94 Cougar where correct for that year up to 95 and some said 97. The data is very inconsistent in trying to find information on the original injector used. The numbers I pulled for the OEM injectors for the 94 Cougar are from the Denso 195500-2630 injector which is supposed to be a duplicate of the Ford F3DZ-9F593 injector. If I could find stats on the F3DZ-9F593 injector, I suspect the stats would be different, including the lb/hr. It would be fair to say it might be 19lbs as Grog said. I suspect the Denso model is 24lbs. Like I said, very inconsistent information on this subject. Finding information on the internet seems to have been over shadowed by selling ads.
 
Ford what it is worth, this Mudstain chart shows 94-98 V6 cars got 14 lb/hr injectors.
Everything else I have seen also indicates that 14 lb/hr are the correct flow rate for your car. If you do indeed have 24 lb/hr injectors in there and your ECM is expecting 14 lb/hr then that will definitely cause problems. You could have them flow tested to verify.
 
First of all, thank you for the input, all of you. It actually puts me back to trying to figure out what is causing the codes 137/173.
The injectors that are in the car now, are the F1ZE-B4C injectors, which are rated at 14lbs. Which would mean by Kevin's numbers are the correct ones, even though Amazon is saying they are not the correct one's... long story, don't get me started.

So the next things to check are my air charge temp sensor wiring (sends a code to the PCM to decrease fuel), my fuel vapor return lines, canister and solenoid (I was working on those last year). Like I said, no idiot light, no rough idle, no mis-fire, etc, etc and nothing to indicate there is a problem, except the running rich codes.

It'll be fine....


....nope, I'm screwed.
 
I don't trust Amazon for much of anything. I sure wouldn't trust their vehicle fitment guide for parts.

You could also test the coolant temp sensor. Also, just because the engine runs like garb with the MAF unplugged doesn't necessarily mean it is sending good data to the ECU when it is plugged in. Unfortunately it isn't real easy to test/diagnose on your car.
 
Oh geez... I used the wrong information....

The injector I pulled from the junk yard 94 Cougar / V6 has the numbers F3DE-B4D-9F593 (Ford).
An injector that RockAuto sold was F3DZ-9F593
In retrospect, it does not matter as they are both the 94-95 Essex V6 BUT....

As you can see from the chart, the injectors I pulled from the yard are indeed correct as as well as the ones from RockAuto.

Just wanted to clear that up. This injector, F3DE-B4D-9F593 is a PITA to find info on as well. Searching now for the lb/hr ratio. It should be the same as the one I have been talking about.
 

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KevinVarnes said:
I don't trust Amazon for much of anything. I sure wouldn't trust their vehicle fitment guide for parts.

You could also test the coolant temp sensor. Also, just because the engine runs like garb with the MAF unplugged doesn't necessarily mean it is sending good data to the ECU when it is plugged in. Unfortunately it isn't real easy to test/diagnose on your car.
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I feel that way about eBay.

The MAF could be out of range, it is possible. I think I accidently sprayed it with brake cleaner once instead of MAF cleaner. I don't know if that would have ruined something or not.

I will check the coolant sensor, but that is new and the coolant temp is correct without failure (dash gauge).

I pulled the upper intake and realized why there is so much varnish in the intake tubes. If the engine is not firing correctly, (my timing was 6deg atc) the valves are allowing unburnt and burnt fuels to pass back into the Intake. Yeah, I am not the best mechanic and why I don't give much advice or work on other peoples cars. But really like working on cars but maybe I should have stayed with pre-1973 cars.

I have the air intake sensor off and am testing it for voltages / tempuratuers. Also testing the wiring to the sensor. I am also going to change out my injectors with the ones that came off the 94 Cougar that are flushed and new seals/filter/cap put on.

I did check the return gas canister and it is hooked up correctly but need to test the line back to the tank is not blocked and the test the solenoid to ensure it is opening and closing. I never smell gas or have issues with gas cap pressure, so I doubt that is an issue. To test the solenoid and tank line, I need to pull the inside fender housing. I have been wanting to clean my air filter anyway, and that is inside the fender well. Good time to do all of this.
 
I got it all back together, good news, I think I fixed the 137/173 codes. Bad news, the car won't start. If I hold the gas peddle to the floor, it will start, sputter and die.

Ugh.
 
Before I am able to really test it and then submit a new Post about it, I think the issue was the Intake Air temp sensor. I put a new one in because the old was the original and the car was having issues with high idle. Before that (besides the codes), it would go to high idle and just not react correctly. The sensor I put in that was new was not in but half way. The OEM as I recall was all the way in, but the new just did not want to go any further, and I did not want to push something that was that hard to tighten down. This time, I had no issues tightening all the way to the lower intake floor. Common sense would say that if that sensor is not all the way into the lower intake, it is not low enough into the air flow to get a proper measurement. I did test the sensor and it was working, by heating / cooling it and watching the resistance go up and down.
 
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Grog6 said:
Wait. If it won't start, how can you say you fixed it?
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I need to check several things today to see why it won't start.

Check the distributor and wires / coil connection.
Check fuel pressure
Check for spark plug spark

The injectors did spray when I cleaned them. The sprayed through all of the tests. Even a crappy injector spray will get ignition.
 
Distributor and wires are good, fuel pressure is 38+ but I have not checked spark. I poured some Berryman's down the intake and got it to run, but it was running real bad, like only a few cylinders where firing and black smoke out the rear. It did get better the longer I let it sit idleing, but it was still running poorly. I tried to restart it again and it would not start. i am thinking a few of the new injectors (old, flushed, cleaned, replaced parts) may actually be bad even though they sprayed.

I have two other injector sets I can contemplate over, as you know.

Weird thing taking out the #1 injector, the ring was melted into the socket and it took me an hour to get it out. I didn't want to break my metal pics and finally had to use a straight pic to get some of the ring out to get a small screwdriver in/under the ring and pull it out. Cleaned all lower intake injector ports of debris and old grease.

I hate when that happens.
 
It's alive again. But with a missing cylinder and white smoke out the drivers side. I suspect a spark plug wire is not connected / missing cylinder. Ran nice despite the mis-fire. Waiting for the engine to cool down so I can check the plug wires.
 
Replaced a plug wire that had a hole in it, made sure it was connected to the spark plug. Today, I ran 2 cans of Berryman's through the injector rail and it still was putting out white smoke, but it ran well other than it sounds like its missing in one cylinder. Either I have a bad injector (or 2) or bad wiring to a cylinder. I suspect the injectors due to their age and it ran fine before I did all of this. Instead of putting the injectors I had in the engine before I started all of this, I am going to look for some new injectors. The price may not be worth it. But one of the one's I pulled, the output side fittings were melted into the head injector socket and I damaged the parts getting them out. They are not the same fittings as my other injectors.

Injector Flush.jpg
 
As Tangina said in Poltergeist "This car is clean"... well... maybe a bit out of context.

I put the injectors back in that were in the car when I first started this crazy escapade and it is running REALLY nice now. I just need to take on a long drive to shake it back into a routine.

Officially, I am retiring this post.

Thanks everyone that had something to say during this journey.
 
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