Dirty Fuel Injectors???

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My 93 GT would not start. The engine cranked, but that's it. The first two questions that came to mind were (1) Is there a spark, and (2) Is there fuel. To answer the first question, I shot some starting fluid in the
throttle body and the car turned over, sputtered and died. So I figured, yes there is a spark, but no there is no fuel... Well a fuel pressure gauge tells me there is 40 PSI at the Schrader valve, so I now figure the injectors are fouled.
Does this make sense or am I missing something obvious?
$62.50 x 8 is a big chunk of change! Can I simply pull the injectors and clean them on my bench?
If I understand the Mustang Unlimited kit properly, it requires the car to be running to be effective and it doesn't run, so am I headed in the right direction by removing and cleaning the fuel injectors myself?
I would certainly appreciate any suggestions or directions.
Thanks!
Joe
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Joe Colella wrote:

I wouldn't jump to the conclusion that the injectors are clogged. They would ALL have to be clogged severely to not allow the engine to run and this is highly unlikely. Maybe you got some bad gas or there is water in the tank. You might try some dewatering additive first or drain the tank and lines before taking the injectors out. You might want to check out the fuel filter too. You might have pressure but not enough flow. Others here might have some more suggestions.
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one can check for bad gas by getting some of the fuel pumped up and putting it into a clear jar and seeing if there are beads of water on the bottom. (very dangeroious to do this, )
When is last time you changed fuel filter? Is gas tank near empty? (if so, more crud on bottom)
pull some of the easy plugs and read them
when is last time you cleaned/replaced air bypass ?
you have to pull top manifold off to get to injectors, the rod could still be in place in the back by firewall, you have to cut that, it holds top and bottom together
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Checking for bad gas... Siphon some gas from the bottom of the tank, right?
Fuel filter could be 5 years old.
Tank is currently 3/4 full, but just before the most recent fill, I did run the tank damn-near bone-dry.
Pull some of the easy plugs and read them... I actually changed the plugs right after pushing the stang into the garage.
Last time I cleaned/replaced the air bypass... Could be 6 years. (Am I bad?)
I am getting the very distinct picture that cleaning the fuel injectors is not a walk in the park!
Is there anything else I should look at before ripping the manifold off?
Thanks, again!!!
Joe
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Changing the fuel filter is easy and cheap... and probably should have been done some time ago.
Really... I could have pressure, but not enough flow? I would not have expected that, but all the same, I will definitely change the fuel filter.
Drain the tank and the lines... I could do that!
Thanks!
Joe
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Steve wrote:

Definitely put some dewatering additive in the tank after draining it. That will clean up any residual water that may be left behind. If you still think it is the fuel injectors then I suggest pulling a couple of the ones that are easy to get to first. If they are in decent shape I wouldn't waste your time pulling them all. One other thing that affects fuel flow is the MAF sensor. I doubt it is bad but it could cause fuel delivery problems if it is defective.
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Injector Condition... After I pull 2 or 3 injectors, how can I tell if they are in good shape? (Gosh, I feel stupid!)
Crud in Tank... Could running the tank empty until the car literally runs out of gas be the root of all my problems?
Should I also flush the fuel line? With gasoline or some other liquid or pressurized air? How about the fuel lines between the fuel line and the injectors?
I can test the MAF sensor, how can I test the fuel pump for proper flow if the pressure reading in not conclusive?
Thanks!
Joe
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change one thing at a time, fuel filter first. add dryer.
then check for bad gas. I got a load at one gas station, lots of water in it. got a hose and ran it into the fuel rail and to a clean jar, cranked the engine a few times, and got jar 1/2 full, lots of water in it, beads at bottom. Gas station had a fuel truck filling up the tanks and stirring up the water at the bottom of the gas station tanks, was a dimond shamrock, now veralio, never got gas from them again.
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Joe Colella wrote:

You can see build up on the nozzle tips but they probably need to be tested for having a proper spray pattern.

Running the tank low shouldn't be a problem normally unless there is a lot of debris in the tank. This would clog your fuel filter.

You car uses a return fuel system so a cranking the engine should flush out the fuel lines fairly quickly.

This isn't an easy task for the DIYer. Try and find a friend with the same car (i.e. 1989-1993 5.0L Mustang) and swap in their MAF and see if it starts. I assume you are using a stock MAF. If so you need to use a stock MAF or one calibrated for you injector size.
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wrote:

FIRST THING, make sure the injectors are being triggered. Put a set of "NOID" lights in place of the injectors on the wiring harnes and make sure they flash. If the injectors are not being signalled to fire, it will never start.
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I was waiting for someone to figure that out!
<clare at snyder.on.ca> wrote in message wrote:

first two

there
the
figured,
pressure gauge

and
car to

right
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and
the
check
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Steve wrote:

One last thing, the fuel pump might be bad. While it might be delivering adequate pressure it might not deliver the flow required.
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wrote:

Impossible. If it is producing specified pressure it is pumping enough to start the engine. Mabee not enough to drive it down the road - but definitely enough to make it start (or at least cough pretty good) Given his fuel pressure, it's not the fuel filter either (although it may still be a good idea to change it when you find out why it's not starting now)
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clare at snyder.on.ca wrote:

It could be the pump. There is a pick up tube with a sock over it. This could get plugged if there is junk in the tank. Unlikely but possible.
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wrote:

If it was plugged totally he would not have full rail pressure. If he has full rail pressure there is enough fuel to start the engine. Mabee not enough to run it, but enough to start it. I stick by my "impossible"
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clare at snyder.on.ca wrote:

I don't think it is the pump either. Usually when pumps go bad they just stop working all together.
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What do you mean by "sputtered"? If you spray a good amount of carb cleaner into the open thottle body, it should run at a high idle for about 2 seconds. Not just "sputter". There is no way ALL the injectors went bad at once unless you ran battery acid through them. I think you better make sure it has good spark by looking at the spark or re-testing your "spray method". Strating fluid will help it try to start if the spark is weak. You can test the MAF by unplugging it. This will put it into "limp in" mode so the ECM wont even look at the MAF. 40 PSI doesn't sound like enough for MPFIed mustang, I would *guess* 60 but I don't know for sure(been way too long). If it is supposed to be 60 it wont run on 40. Look it up. (buy a book) BTW, fuel filters are very cheap *hint, hint*
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On Tue, 27 Nov 2007 11:37:36 GMT, "Joe Colella"

I have to ask a dumb question but, have you tried holding the throttle on the floor while cranking the engine? This will put the system in clear mode in the event you have flooded it. Yes - that is possible with EFI. Flooring the throttle turns off the injectors to clear it while cranking. If you should also try to extract any fault codes from the ECM.
Look here for how: http://www.fordfuelinjection.com/?p 
For codes: http://www.fordfuelinjection.com/?pE
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wrote:

When I followed the directions from the website above, I did not hear any clicks and after 1.5 minutes the fuel pump was still running. I then re-connected the STI to the neg term and tried it again with the same results. Now what do I do???
Joe
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I second the idea of the TFI module.Dont buy a cheapo,get one from Summit (accel) or motorcraft.when they die they are erratic(I drive with a spare, ask my wife how they die in traffic,LOL).Get a socket for the tiny screws from Napa.Use thermal grease or it will fry in short order.If you think the fuel system is plugged or pump is erratic, bang on the tank see if it starts to run,or when you first turn the key on to start you should hear the fuel pump run for a few seconds until it comes up to pressure..If car runs when gas is sprayed in the throttle body It could indicate plugged filter or sock I suppose.I would expect the pump to have been noisy lately also.I think 40 lbs of pressure is normal.If plugged you could prove if by opening up a line and letting the pump run the gas out of the line in order to clean them.Remember the computer needs a reliable voltage in order to work, possible ground and connector problems.Good luck,Youll find it.Oh yeah,my brother in law had a fuel pressure regulator die on his ford van exhibiting the same symptoms (same basic system) he also had bad ground connector problems.
wrote:

figured,
and
to
right
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