Hey guys have a pretty detailed question.

Okay so. as far as i can tell the 96-98's models of my car had injectors with jettronic connectors (square ish).

But my 99 has uscar more of a rounded.

The guy that owned the car before me changed 1 injector and the one injector he changed was a jettronic which is opposed to the uscars that were in mine from stock.

along with installing this injector he of coarse spliced a jettronic connector into the harness to compensate.
a couple weeks ago I was listening to my injectors because i started developing bad gas mileage.

when i was listening to the injectors I noticed that the one he changed with the jettronic connector sounded different than all the other 7. more of sloppy noisy tick like it had noise interference in it.

My question is what are the differences injectors that are jettronic and uscar? how would putting in a jettronic injector effect a car that has uscar connectors? and or what would happen if a car had 7 injectors that were different.

Regardless im gonna splice in the proper connector. and change all injectors.

This post was edited by Historic on May 6 2017 08:27pm

As far as varying - Aside from the plug, some injectors operate at different ohms. Some are "low impedance" (peak & hold) injectors. The others are high impedance (saturated) injectors. See what your car comes with stock, and see if the new injector matches those specs.


but chances are, if you hear the injector clicking - it's probably working. It might just sound different from the rest. They are simple little electromagnets... The question is - Are you injecting the proper amount of fuel? Matched with the other 7 injectors?

This post was edited by OldAndyAndTheSea on May 6 2017 09:36pm

Hey thanks for the response.

Thats my question were with flow rates for the previous years different? its hard to find this out.. Really im trying to find the source of an issue with this car. it pings and clatters when cold and goes away when warm yet is sluggish at accel. ironically the noise comes from the same bank that oddball injector was installed
bad gas mileage.

I guess a more simple question is can an injector have a different connector but have all the same specs?
They both read around the same ohm's

rockauto has listings for the injectors http://www.rockauto.com/en/catalog/ford,1999,taurus,3.4l%20v8,1354834,fuel%20&%20air,fuel%20injector,6224

the bottum injector has USCAR connects while the others are the older style jettronics

This post was edited by Historic on May 6 2017 09:52pm

Definitely. The injector plug style varies from make to make. As long as they flow is the same, and are being triggered, there shouldn't be an issue..I guess the spray patterns could differ...but I don't see that as an issue, really. The only way to check the specs of the new, oddball, injector is to find some sort of stamp/ serial number and cross reference it with the google machine.

But I'd definitely revert eveything back to stock, regardless.

This post was edited by OldAndyAndTheSea on May 6 2017 10:10pm

You wouldn't happen to of heard of an injector causing such an issue would you?

The car starts knocks when cold couple of seconds. the idle sounds fine smooth and perfect. when i hit the gas raise it up to about 1k+rpm ish I hear a weird fluttering sorta clattery noise.
also if I blip the throttle at idle the rpms will dip low sometimes nearing stalling. but rpms raise back up to normal quickly.

if I start the car hot it will start run rough chug and or totally stall sometimes. if I hit the gas it will smooth itself but.

I noticed if going fast and im on a moderate decell the engine rpms while start dip like crayz and raising back like going up and down. only on decelll.

its not rod bearings clogged muffler coils or spark plugs i changed that all. I measured valve clearances and felt the tension of the timing chains.
it doesnt burn oil or have a head gasket issue. either. changed o2 sensors cats egr tps and maf sensors.

only thing I haven't changed is the injectors.
we cant find the problem.

This post was edited by Historic on May 6 2017 10:26pm

A couple of those things actually sound like a vacuum leak to me.

You typically pull most vacuum pressure at idle, and upon deceleration. If the car is dying out on decel, it's not getting enough fuel - because it's getting too much air...but your foot is basically off the throttle - closing the throttle body - the air is getting in elsewhere leaning the mixture, perhaps.

surging and pulsing rpms (like going from 1000-1500 up and down up and down etc) is a sign of a lean mixture.

Have you done any checks for vacuum leaks?



Also check your throttle positioning sensor connections, and confirm it is operating within specifications. That can also have some impact to drivability in some cars.

This post was edited by OldAndyAndTheSea on May 6 2017 11:58pm

I actually checked for vacuum leaks many times with starter fluid and I really drenched it on and listened to the rpm's and also played around and adjusted the tps sensor with different voltages.

shes got a whole lot a intake going on. Now i'm starting to wonder whats going on with compression and or valves.

I got a rich code and a p0420. Now I am starting to wonder if an intake valve out of clearance.

along with changing the injectors ill throw in a new fuel press regulator.

maybe its possible that an injector or regulator is leaking and the cpu panics cutting fuel.



This post was edited by Historic on May 7 2017 12:42am

with the p0420 and loss of fuel mileage are you sure your catalytic converter isnt getting clogged up?

I changed the cats myself and seemed to do the same thing.

ok. another reason for p0420 is: Leaking fuel injector or high fuel pressure. maybe get that injector and plug swapped out asap, clear out any dtc and see if that clears it up seeing as you planned on that anyway