1994 Mustang GT project need help.

Sunburnt94

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I am currently trying to restore my dads 1994 mustang GT that has been sitting since 2009. Currently has cold air, EGR delete, cat back exhaust, new TPS, new fuel pressure regulator, and new IAC. Started by dropping the fuel tank and dumping the old fuel, filling her up with some fresh fuel, new oil, and some spark plugs and wires. Started up but it was 'idling' at 2k RPM but it was running and would stay running. Decided to replace the IAC when the car was no longer getting pip signal from the distributor or spark. I replaced the distributor and coil, timed it to 10* BTC, and double checked firing order (all good). Now since then I am barely able to keep the car running. I am lost on where to start with what is going on now. The car starts, never exceeding 1k RPM and dies just as quick. Now every once in a while it will start for a couple of seconds rev on its own to 2k rpm but when it tries to go down to idle rpm it dies. When it does start like this and I push on the throttle it begins to die, when I let go it jumps back up to 2k, and when it tries to go back down to idle I mash the throttle to the floor it 'runs' but doesn't go above 500 rpm with throttle to the floor. One more thing is that when it is 'running' at below 500 rpm there is a pop or bang sound from the passenger side and when it pops it jumps rpm and pops again jumps rpm till its going back up to 2k rpm and is giving a strong smell of fuel from the passenger side. Giving it any sort of throttle wants to kill it but for whatever reason throttle to the floor keeps it running under 500rpm. I've checked vacuum lines those seem to be good and fuel pressure is 10 psi and stays when it starts to run at 2k and loses pressure after it dies. Just don't know where to go next possibly re-doing vacuum lines, PCV? I'm lost on this one. Thanks for the read.
 

95opal

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I am currently trying to restore my dads 1994 mustang GT that has been sitting since 2009. Currently has cold air, EGR delete, cat back exhaust, new TPS, new fuel pressure regulator, and new IAC. Started by dropping the fuel tank and dumping the old fuel, filling her up with some fresh fuel, new oil, and some spark plugs and wires. Started up but it was 'idling' at 2k RPM but it was running and would stay running. Decided to replace the IAC when the car was no longer getting pip signal from the distributor or spark. I replaced the distributor and coil, timed it to 10* BTC, and double checked firing order (all good). Now since then I am barely able to keep the car running. I am lost on where to start with what is going on now. The car starts, never exceeding 1k RPM and dies just as quick. Now every once in a while it will start for a couple of seconds rev on its own to 2k rpm but when it tries to go down to idle rpm it dies. When it does start like this and I push on the throttle it begins to die, when I let go it jumps back up to 2k, and when it tries to go back down to idle I mash the throttle to the floor it 'runs' but doesn't go above 500 rpm with throttle to the floor. One more thing is that when it is 'running' at below 500 rpm there is a pop or bang sound from the passenger side and when it pops it jumps rpm and pops again jumps rpm till its going back up to 2k rpm and is giving a strong smell of fuel from the passenger side. Giving it any sort of throttle wants to kill it but for whatever reason throttle to the floor keeps it running under 500rpm. I've checked vacuum lines those seem to be good and fuel pressure is 10 psi and stays when it starts to run at 2k and loses pressure after it dies. Just don't know where to go next possibly re-doing vacuum lines, PCV? I'm lost on this one. Thanks for the read.

For starters did you replace the fuel filter?
Are you sure your seeing 10 psi fuel pressure?
With the car sitting that long id suspect the injectors could be clogged up.
Injector o-rings may also be leaking. I would take the injectors out and and send them to be cleaned and rebuilt.
 
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Sunburnt94

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For starters did you replace the fuel filter?
Are you sure your seeing 10 psi fuel pressure?
With the car sitting that long id suspect the injectors could be clogged up.
Injector o-rings may also be leaking. I would take the injectors out and and send them to be cleaned and rebuilt.

Yes I've changed the fuel filter as well and hooked up a fuel pressure tester to the Schrader valve holds 10 psi after cranking the engine and quickly dumps off that pressure. The rails should hold some kind of pressure after building pressure or no? I had pulled #1 cylinder spark plug just to verify timing as Musturd had suspected and the plug is fouled. So seems more fuel related I am guessing. Also is there anything in the passenger side fender well that would be worth looking at? I see fuel lines going through there and a vacuum line do they connect to anything or are they just straight to the tank? Thanks
 

Daryl

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I am currently trying to restore my dads 1994 mustang GT that has been sitting since 2009. Currently has cold air, EGR delete, cat back exhaust, new TPS, new fuel pressure regulator, and new IAC. Started by dropping the fuel tank and dumping the old fuel, filling her up with some fresh fuel, new oil, and some spark plugs and wires. Started up but it was 'idling' at 2k RPM but it was running and would stay running. Decided to replace the IAC when the car was no longer getting pip signal from the distributor or spark. I replaced the distributor and coil, timed it to 10* BTC, and double checked firing order (all good). Now since then I am barely able to keep the car running. I am lost on where to start with what is going on now. The car starts, never exceeding 1k RPM and dies just as quick. Now every once in a while it will start for a couple of seconds rev on its own to 2k rpm but when it tries to go down to idle rpm it dies. When it does start like this and I push on the throttle it begins to die, when I let go it jumps back up to 2k, and when it tries to go back down to idle I mash the throttle to the floor it 'runs' but doesn't go above 500 rpm with throttle to the floor. One more thing is that when it is 'running' at below 500 rpm there is a pop or bang sound from the passenger side and when it pops it jumps rpm and pops again jumps rpm till its going back up to 2k rpm and is giving a strong smell of fuel from the passenger side. Giving it any sort of throttle wants to kill it but for whatever reason throttle to the floor keeps it running under 500rpm. I've checked vacuum lines those seem to be good and fuel pressure is 10 psi and stays when it starts to run at 2k and loses pressure after it dies. Just don't know where to go next possibly re-doing vacuum lines, PCV? I'm lost on this one. Thanks for the read.
Had to adjust my timing too. Made a world of difference and it behaves how it should at start up, then dumps down to roughly 900rpm idle. Simple fix: start it up, slightly loosen the distributor bolt, rotate distributor and listen to it drop rpm’s! Tighten bolt.
 

dalpoas83

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Idk the exact spec but you should have like 30 psi of fuel pressure
 
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Sunburnt94

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Had to adjust my timing too. Made a world of difference and it behaves how it should at start up, then dumps down to roughly 900rpm idle. Simple fix: start it up, slightly loosen the distributor bolt, rotate distributor and listen to it drop rpm’s! Tighten bolt.
Definitely could tell the difference when I was first setting timing when I replaced the distributor. Still does not like to idle however or does not like any throttle.
 
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Sunburnt94

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Idk the exact spec but you should have like 30 psi of fuel pressure
Yeah I am getting no where near 30. Is there a good way to test or know whether it's a bad fuel pump or an injector that is stuck open? Definitely get that strong smell of gas when it 'starts' and any throttle kills it.
 

94IndyPace

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Good possibility the fuel line from the pump to the pick up is rotted away. If the pump is scavenging then you won’t see pressure
 

Rons95GT

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Wouldn’t affect fuel pressure but clogged exhaust causes weird problems also. If it sat that long make sure rodents didn’t build nests somewhere. I saw on episode of Rick’s restorations the other night where rodents had taken nuts all the way up the exhaust and into the combustion chamber on a motorcycle. ‍
 

maillemaker

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Also is there anything in the passenger side fender well that would be worth looking at? I see fuel lines going through there and a vacuum line do they connect to anything or are they just straight to the tank? Thanks
There is a vacuum line that runs through a solenoid that then goes behind the passenger fender. It goes to the charcoal evap canister. Mine was heavily rotted.
 
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Sunburnt94

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Thank you all for the replies and ideas. Went ahead and just ordered some fuel injectors and will be installing those this weekend. When I was installing the new exhaust I did not see any signs of rodents or anything clogging the old exhaust. Anything else I may as well replace/take a look at while I've got the upper manifold off?
 
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Sunburnt94

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There is a vacuum line that runs through a solenoid that then goes behind the passenger fender. It goes to the charcoal evap canister. Mine was heavily rotted.
Yeah when I was removing the intake manifold it was completely rotted away from where it connects so there is one of my fuel problems.
 
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Sunburnt94

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Well she runs! New injectors and some vacuum line and she ran and stayed running. Kind've still rev hangs for a couple seconds but idles great now. Only able to run her in valet mode right now since the alarm system is constantly going off. I've been trying to find ways to remove it entirely. There any good forums on here that take you through this? Just can't seem to find any myself for some reason.
 

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