testing a fuel injector

Ironhead

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hey i got a magnum 488 v-10 in my 3/4 ton ,,,i think i have a fuel injector screwing up ,,,how do you test a fuel injector ,,,and how ,,,is there a voltage test to do this or is it a presure test ???
 
what is it doing / not doing?

Depending on your symptom, you can actually listen to it, or get it flow checked.
 
when i first start up and take of it sputters ,,,if i stick it in neutrel and gunn it once or twice it takes off ,,fine ,,,if i let it warm up a second or two and take off it almost never does it ,,,if i just let it sputter it will start blowing out smoke that smells rich as hell ,,sometime if i just floor it when it does this it will backfire then vroom goes fine ,,,only does it when i start it up once it clears it runs fine ,,,its like it floods out at startup ,,,,make any sense??
 
when it started doing it i replaced plugs and wires but still does it
 
hmm so many things could cause that...

If it does it when first started only, I would first look into sensors (startup) (TPS, MAP, IAC, etc..) Seems once it transitions from open to closed loop your fine...

I doubt its a F/I or you would have constant issues. MAP would be the first...

How does it do WOT when warmed up?
 
mmm that makes sense ,,,yes it only does it on startup only ,,never when running,,,wide open seems ok too burns tires for a 3/4


also wont all three of those throw a code if not working right ,,,cause i get no codes at all,,,also since i have had this truck the milage thingie on center roof consule never worked ,,wondering no if its not tied in to one of the sensors
 
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Figure out what sensors are in play when vehicle is in open loop (cold) and start checking those first.
 
SANTEEN said:
Figure out what sensors are in play when vehicle is in open loop (cold) and start checking those first.

lol i was hoping for a little more specifics lol;) did check price the iac and map are cheap under 30 bucks each ,,,
 
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the fuel consumption calculation is derived from the injector on-time. If anything shot gun a couple new sensors in there. then pull plugs and check em. You will quickly see if one of em is fouled or lean
 
FerrariTruck said:
the fuel consumption calculation is derived from the injector on-time. If anything shot gun a couple new sensors in there. then pull plugs and check em. You will quickly see if one of em is fouled or lean


thats confusing SHOt gun ,,,what sensors in there,, and were is injector on time ,,not trying to bitch but that makes no sense to me ,??? you sure your name aint dom !
 
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ok got a book and tested iac voltage reads good ,,,map sensor reads good ,,,now one thing i see is that this old truck still has the oem o2 sensors ...from 99 with 108,000 plus ,,i dont get any codes but does anyone think i should replace them anyway ??
 
Injector

If No CEL On, I Would Take A Look At The Injector Seals, If Good, You Can Ohm Out The Injectors. O 2 Sensor Would Usually Throw A Code And The CEL. Also Look Into The Water Temp Sensor For THE COMPUTER!
 
DIABLO_X22 said:
If No CEL On, I Would Take A Look At The Injector Seals, If Good, You Can Ohm Out The Injectors. O 2 Sensor Would Usually Throw A Code And The CEL. Also Look Into The Water Temp Sensor For THE COMPUTER!


ok ,,,when i ohm out injectors am i looking for just an open and closed continuity,,or is there a ohm reading plus or minus im looking for




opps never mind i found it 12 ohms
 
Skittle dont question them,

call the local napa or a commercial truck center,

take the injectors to them and have them checked, usually dont cost more than a couple bucks.

last set I had tested the guys werent busy and did it for free , dont take but a couple minutes bud.

ohming foaming bloaming does notthing but tell you if they work, they dont tell you if its actually flowing.

gettem tested booger brain:D
 
problem with the older magnum v10 stink i have to take the intake off to remove them ,,:mad: ,,,im almost tempted to just replace them ,,,since it has 100,000 plus on it i just cant see reinstalling the old ones after all that work :mad:
 
DIABLO_X22 said:
Look Into The Mass Air Flow Meter, They Make A Spray To Clean It.


checked voltage on it with engine off and running and its in perameters ,,,no codes have ever shown up,,,and i see nowere in book that shows a mass air meter ,,,
 
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