A few weeks ago I got my 73 Mustang 351 Cleveland out of the garage. It ran great driving down the road, but at idle it ran real rough. It never died, but very rough. Yesterday I got it back out of the garage, same thing, idled very rough. I started it three different times and I can't seem to figure out what's going on. On the 4th time, the car wouldn’t start?? I hear an odd noise toward the back left of the engine compartment that I don’t recognize. Of course this was only when I had it running. Any ideas?
ENGINE TROUBLE
- Thread starter JREID2
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Not enough to go on.
First guess would be vacuum leak. PCV hose got knocked off.
So check that.
Then check the ignition system. See if you are getting spark.
Don't touch the carb until you have eliminated the other stuff.
Are you running points still?
First guess would be vacuum leak. PCV hose got knocked off.
So check that.
Then check the ignition system. See if you are getting spark.
Don't touch the carb until you have eliminated the other stuff.
Are you running points still?
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I got a great deal once on a non running 65. Towed it home plugged the vacuum line back into the transmission and it ran fine.
PCV valve/hose is where you add oil. The cap has a grommet that holds the metal (or plastic) valve in place. There is a hose that attaches to the top of the valve and goes to the back of the carb. Tough to miss the fitting on the carb, it is the largest one sticking straight out of the back. This is how Ford set it up. It could have been modified at some point by previous owners.
You could save some time by posting a couple pics of your engine here. Most of the guys here can help identify problems from pics.
You could save some time by posting a couple pics of your engine here. Most of the guys here can help identify problems from pics.
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ok, so I took some pics for review. I noticed the aluminum coil hose was disconnected(pic 4), the plastic black ring around the carb is broken? I see a loose black wire(pic 3), not sure if this is important? I also have a pic of the filter, looks dirty to me? Do any of these things add up to my issue? Do you notice anything else? thanks!
forgot air filter pic...here you go.
forgot air filter pic...here you go.
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looks like a Holley 4160 on a Cleveland with Ram Air, which could be a strong runner if you get it smoothed out. I dont know 73's so im not your best comments but the silver hose hooks to the side of the blue air cleaner housing. its only for fuel tank fumes so doesnt really affect idle, and slips on/off the plastic connector easily. I see the PCV in the drivers side valve cover cap, though not sure where it is connecting to the carb. Also you have AC which has additional vac hoses i believe and takes me out because my car doesnt have AC and i havent spent any time with cars that do. I posted a vac hose diagram to a thread last week, search Autozone. Always good to check if your hoses are connected properly...plug wires in place, cap is secured...a rough idle could be a vac hose, an intake leak due to bolts working loose, carb base leak. You might give more details on the sound by the rear passngr side?
We are not going to be much help to you looking at pictures. 'running rough' is difficult to diagnose and even more difficult on the internet.
If it was a "Doesn't start" or "Won't turn over" that is much easier to give a step by step troubleshooting advice.
Then toss in 40 years of previous owners doing stuff and it can be difficult to figure out a running rough issue.
How interested are you in learning lots about how your engine works?
First off, do you know if you have points or not on your distributor? If you don't know how to check let us know and we can help. Points are very very old school and the source of many bad running issues.
You should spend a few bucks on a vacuum gauge. A timing light and, if you have points, a dwell meter.
My only other advice at this stage is "don't start messing with the carb". Lots of times we like to go after the carb because it has things we can mess with. Avoid that temptation. We need to confirm there are no vacuum leaks and the ignition system is working correctly before we start turning screws on the carb.
If it was a "Doesn't start" or "Won't turn over" that is much easier to give a step by step troubleshooting advice.
Then toss in 40 years of previous owners doing stuff and it can be difficult to figure out a running rough issue.
How interested are you in learning lots about how your engine works?
First off, do you know if you have points or not on your distributor? If you don't know how to check let us know and we can help. Points are very very old school and the source of many bad running issues.
You should spend a few bucks on a vacuum gauge. A timing light and, if you have points, a dwell meter.
My only other advice at this stage is "don't start messing with the carb". Lots of times we like to go after the carb because it has things we can mess with. Avoid that temptation. We need to confirm there are no vacuum leaks and the ignition system is working correctly before we start turning screws on the carb.
I would suggest the basic first steps, check your distributor and all your wires, make sure you're not missing a cylinder. Also check all your plugs, fully seated, good gap, not fouled.
As for that line coming off your harness that's not connected (the electrical one) that looks like it should be the plug for your under hood light (trace that wire loom, if it leads back to the always hot side of the starter solenoid that's definitely what it is) so nothing to worry about and should have any effect on the current situation
As for that line coming off your harness that's not connected (the electrical one) that looks like it should be the plug for your under hood light (trace that wire loom, if it leads back to the always hot side of the starter solenoid that's definitely what it is) so nothing to worry about and should have any effect on the current situation
72HCODE
"My World is Fire and Blood"
It will be very hard to diagnose things over the internet given limited description and abilities of your skill set.
but lets start with Pic 4 the aluminum coil hose that is disconnected is the heat riser.
on cold starts the hose in conjunction with the air cleaner base(blue) brings heated fresh air from the area of the exhaust to the carburator intake through the air filter. the idea is hot air will heat up the intake mixture when the engine is cold to help bring the engine up to operating temperature faster. when 180-190 degrees is reached a heat sensor vacuum motor turns on in the air cleaner base, and a flap opens allowing colder air from the top of the engine bay to feed into the engine, this helps stabilize the intake air tempature and keep the motor in a happy heat range for normal operation.
broken black ring around the carb. that would allow in filtered air to enter the engine intake, not a good thing but would not cause a vacuum leak.
the disconnected wire in pic 3 it is hard to make out.
but if the wire connector is round that is the power for the A/C compressor( you appear to have a A/C compressor on your car that i can see in the photos.)
if the plug is flat and looks like it is keyed for 2 wires but only has one inside that would be the connection for the Anti-Diesel solenoid.
The anti Diesel Solenoid is a electrical activated plunger that is only energized when the engine is running. It sits on the OEM carburetor and is designed to raise Idle rpms up all the time but when the engine is shutdown it turns off and allows the throttle arm on the OEM carburator to fully drop down and close. This allowed ford to raise the idle RPMS on A/C cars with automatic transmissions but stop the engines from dieseling upon shutdown because the idle was too high for normal operation and when shutdown the engine would actually continue running when it should be off because the engine was still hot and getting too much air to correctly shutdown.
some of this could have an effect on idle but i would start else where.
----------
first you could have a slight vacuum leak you would need to inspect all vaccum lines on your car and you would have to inspect all the check valves on your car.
the Brake booster has a check valve and should be inspected to see if it is blown.
you have a A/C car, that means you should have a black vacuum canister on the passenger engine apron by the blue fuel charcoal canister. the Vacuum canister is responsible for powering the vacuum motors in the dash board that run all the climate control systems. There is a check valve on the canister that needs to be inspected, and additionally you could have blown parts in the A/C system that are causing a vacuum leak as well.
you have a 1973 which has a EGR system, and a PCV system that can cause addition problems with vacuum leaks and clogged up parts of the emissions system that will cause a poor idle as well.
The base of the Carb might have a EGR plate and a EGR valve and that could be completely clogged up with soot and debre or it could be blown.
you do not have a history with this car so you have no idea what the people that owned it before you did.
that almost leads you to start over and see everything about the engine and its mechanical condition and slowly work up through ignition and fuel condition and the vacuum system so you know everything is working correctly.
as it stands you have a bunch of small problems that all effect each other and turn into a larger issue.
obviously if something is viably broken then you need to fix it to rule it out.
next you will need some tools to work on the car if you don't have it.
a vacuum gauge.
a vacuum hand pump.
these will be useful in routing out a vacuum leak.
a timing light and dwell/tach/voltage gauge will help see how the engine is running in addition to the vacuum gauge.
poor idle can run a big range. vacuum leaks, mechanical damage, poor maintenance, miss adjusted carburetor.
problem is we would need more information which means you need tools like a compression tester to know the condition of the motor.
you could try things like. inspecting the engine for other broken or leaking items. disconnecting all vacuum accessories from the motor and pluging all the vaccum trees on the intake manifold. seeing if there is an improvement.
changing out the PC Valve(PCV) which can cause vacuum leaks. inspecting and repairing the EGR system (Exhaust Gas Recycle) that can also cause major problems.
next the carb might be due for a total rebuild. the idle air bleeds might be set incorrectly that can also cause poor idle.
a air filter would have to be completely clogged to the point you couldn't see sun light through it before it would effect engine idle performance.
the condition of the current spark plugs will tell you a lot also.
google how to read spark plugs, they can tell you tons of things about timing issues and if you idle is too lean or rich, and show mechanical damage.
well if you are new you have a big job. first you want to identify everything under the hood and understand why it is there and what it does. that will help you in taking it out and fixing it if needed.
you may have a clogged up fuel filter, the fuel lines might be clogged. the tank could be full of rust.
the vapor return system might be clogged with fuel varnish.
all can cause a poor idle.
the engine might be worn out and valves might be worn out.
the coil might be going. maybe it just needs new plugs, wires and a rotor and cap for a tuneup. many many things can be the cause.
This is why history is so important to know. Did the motor ever run correctly in thee last 5 years. if it did what changed?
this is why many people buy a classic car and the first thing they do when the history is unknown is compression test. Vacuum gauge reading, complete engine tune up, plugs wires, cap, rotor, Coil, points if needed.
replace oil, oil filter, possibly water pump, flush the rad, and replace all fluids,
that helps rule out ignition troubles. next replace the fuel filter or even cut the fuel line and see how much crap inside the tank washes out, if its full of rust you know you will most likely replace or overhaul the fuel system and maybe replace the fuel pump also. that would also be a carb overhaul.
that gets you to a clean start of history you can work from and rule out things.
this will seem over whelming but you have to work the problem one area at a time and build up your knowledge of the vehicle.
but lets start with Pic 4 the aluminum coil hose that is disconnected is the heat riser.
on cold starts the hose in conjunction with the air cleaner base(blue) brings heated fresh air from the area of the exhaust to the carburator intake through the air filter. the idea is hot air will heat up the intake mixture when the engine is cold to help bring the engine up to operating temperature faster. when 180-190 degrees is reached a heat sensor vacuum motor turns on in the air cleaner base, and a flap opens allowing colder air from the top of the engine bay to feed into the engine, this helps stabilize the intake air tempature and keep the motor in a happy heat range for normal operation.
broken black ring around the carb. that would allow in filtered air to enter the engine intake, not a good thing but would not cause a vacuum leak.
the disconnected wire in pic 3 it is hard to make out.
but if the wire connector is round that is the power for the A/C compressor( you appear to have a A/C compressor on your car that i can see in the photos.)
if the plug is flat and looks like it is keyed for 2 wires but only has one inside that would be the connection for the Anti-Diesel solenoid.
The anti Diesel Solenoid is a electrical activated plunger that is only energized when the engine is running. It sits on the OEM carburetor and is designed to raise Idle rpms up all the time but when the engine is shutdown it turns off and allows the throttle arm on the OEM carburator to fully drop down and close. This allowed ford to raise the idle RPMS on A/C cars with automatic transmissions but stop the engines from dieseling upon shutdown because the idle was too high for normal operation and when shutdown the engine would actually continue running when it should be off because the engine was still hot and getting too much air to correctly shutdown.
some of this could have an effect on idle but i would start else where.
----------
first you could have a slight vacuum leak you would need to inspect all vaccum lines on your car and you would have to inspect all the check valves on your car.
the Brake booster has a check valve and should be inspected to see if it is blown.
you have a A/C car, that means you should have a black vacuum canister on the passenger engine apron by the blue fuel charcoal canister. the Vacuum canister is responsible for powering the vacuum motors in the dash board that run all the climate control systems. There is a check valve on the canister that needs to be inspected, and additionally you could have blown parts in the A/C system that are causing a vacuum leak as well.
you have a 1973 which has a EGR system, and a PCV system that can cause addition problems with vacuum leaks and clogged up parts of the emissions system that will cause a poor idle as well.
The base of the Carb might have a EGR plate and a EGR valve and that could be completely clogged up with soot and debre or it could be blown.
you do not have a history with this car so you have no idea what the people that owned it before you did.
that almost leads you to start over and see everything about the engine and its mechanical condition and slowly work up through ignition and fuel condition and the vacuum system so you know everything is working correctly.
as it stands you have a bunch of small problems that all effect each other and turn into a larger issue.
obviously if something is viably broken then you need to fix it to rule it out.
next you will need some tools to work on the car if you don't have it.
a vacuum gauge.
a vacuum hand pump.
these will be useful in routing out a vacuum leak.
a timing light and dwell/tach/voltage gauge will help see how the engine is running in addition to the vacuum gauge.
poor idle can run a big range. vacuum leaks, mechanical damage, poor maintenance, miss adjusted carburetor.
problem is we would need more information which means you need tools like a compression tester to know the condition of the motor.
you could try things like. inspecting the engine for other broken or leaking items. disconnecting all vacuum accessories from the motor and pluging all the vaccum trees on the intake manifold. seeing if there is an improvement.
changing out the PC Valve(PCV) which can cause vacuum leaks. inspecting and repairing the EGR system (Exhaust Gas Recycle) that can also cause major problems.
next the carb might be due for a total rebuild. the idle air bleeds might be set incorrectly that can also cause poor idle.
a air filter would have to be completely clogged to the point you couldn't see sun light through it before it would effect engine idle performance.
the condition of the current spark plugs will tell you a lot also.
google how to read spark plugs, they can tell you tons of things about timing issues and if you idle is too lean or rich, and show mechanical damage.
well if you are new you have a big job. first you want to identify everything under the hood and understand why it is there and what it does. that will help you in taking it out and fixing it if needed.
you may have a clogged up fuel filter, the fuel lines might be clogged. the tank could be full of rust.
the vapor return system might be clogged with fuel varnish.
all can cause a poor idle.
the engine might be worn out and valves might be worn out.
the coil might be going. maybe it just needs new plugs, wires and a rotor and cap for a tuneup. many many things can be the cause.
This is why history is so important to know. Did the motor ever run correctly in thee last 5 years. if it did what changed?
this is why many people buy a classic car and the first thing they do when the history is unknown is compression test. Vacuum gauge reading, complete engine tune up, plugs wires, cap, rotor, Coil, points if needed.
replace oil, oil filter, possibly water pump, flush the rad, and replace all fluids,
that helps rule out ignition troubles. next replace the fuel filter or even cut the fuel line and see how much crap inside the tank washes out, if its full of rust you know you will most likely replace or overhaul the fuel system and maybe replace the fuel pump also. that would also be a carb overhaul.
that gets you to a clean start of history you can work from and rule out things.
this will seem over whelming but you have to work the problem one area at a time and build up your knowledge of the vehicle.
Guys, one more quick update for the night. I started the car up and it smells super "rich" while idling poorly. it revs up fine. At idle it seems to work really hard and again there is a Strong fuel/ exhaust smell under the good. I wished one of you guys lived here In KC!!
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check the line that runs vacuum to the transmission modulator I had the same issue yesterday rich smell running crappy fixed line at modulator and it was problem solved.
72HCODE
"My World is Fire and Blood"
the hose in the photo if you can back trace it to see what it is connected to on the other end might help.
it could be 3 different things off the top of my head.
I can see your heater core control valve in the photo is hooked up so it isn't that.
1) possible Vacuum feed for the Air cleaner base.
2) Vacuum canister feed for the air reserve can A/C system.
3) feed to the DVCV if you have one.
4) fuel bowl vent line to the charcoal can.
i could think of a few more too. you have lots of things in the way to get a clear idea of who/what/where
transmission modulator.
the modular is located under the car, usually above the transmission cross brace. it is a vacuum motor, that will have a rubber tube connected to it, this tube will connect to a metal hard line that runs up the top of the transmission and up to the back side of the engine where the oil sensor is. the hard line then connects to a rubber soft line again and goes into the engine intake manifold vacuum tree where some other vacuum hoses will connect to.
The vacuum modulators job is to alter the shift points of the transmission based on engine load, there is a rod that connects inside the trans to the gear shifter, the modular holds this rod and it moves via a air bladder inside that is adjustable and bows in and out due to the amount of vacuum coming from the engine. there is a mechanical/hydraulic point that causes the automatic trans to shift and then you have a vaccum load override in addition to a 3rd gear override via the kick down rod on the drivers side of the carburator throttle linkage. they all compensate for situations where the trans must shift.
the hose on the modulator can fall off and cause a leak.
Look under the car on the passenger side, just above the back of the transmission where the transmission pan is.
will look like this
it could be 3 different things off the top of my head.
I can see your heater core control valve in the photo is hooked up so it isn't that.
1) possible Vacuum feed for the Air cleaner base.
2) Vacuum canister feed for the air reserve can A/C system.
3) feed to the DVCV if you have one.
4) fuel bowl vent line to the charcoal can.
i could think of a few more too. you have lots of things in the way to get a clear idea of who/what/where
transmission modulator.
the modular is located under the car, usually above the transmission cross brace. it is a vacuum motor, that will have a rubber tube connected to it, this tube will connect to a metal hard line that runs up the top of the transmission and up to the back side of the engine where the oil sensor is. the hard line then connects to a rubber soft line again and goes into the engine intake manifold vacuum tree where some other vacuum hoses will connect to.
The vacuum modulators job is to alter the shift points of the transmission based on engine load, there is a rod that connects inside the trans to the gear shifter, the modular holds this rod and it moves via a air bladder inside that is adjustable and bows in and out due to the amount of vacuum coming from the engine. there is a mechanical/hydraulic point that causes the automatic trans to shift and then you have a vaccum load override in addition to a 3rd gear override via the kick down rod on the drivers side of the carburator throttle linkage. they all compensate for situations where the trans must shift.
the hose on the modulator can fall off and cause a leak.
Look under the car on the passenger side, just above the back of the transmission where the transmission pan is.
will look like this
Thanks 72HCODE, I will check this out. The back trace on the unattached hose can be seen in my picture. It connects to the front of the air filter housing. The blue raised portion of where the air filter sits. Not sure of the technical terminology.
72HCODE
"My World is Fire and Blood"
ok hard to see in photos, if the hose is going to the airbase.then that could be the source for a big leak.
there should be a bimetal heat sensor underneath the air cleaner base. its part of the base, if you lift it up and flip it over you will see it near the carburator hole on the passenger side
first it doesn't look like your aircleaner base as a AUX port on it which would be the drivers side, cause its a ram air base.
So the hose should go from the Manifold vacuum tree on the intake, to the bimetal sensor, then a second hose will go from the bimetal sensor to the vacuum motor on the heat riser.
if the first hose popped off the sensor then that would be a source of a decent size vacuum leak at idle.
the sensor will look like a round piece of bare metal with 2 tongs sticking out of it. the tongs are suppose to have 2 hoses connected to it.
this is the sensor that drives the flapper for the heat riser we talked about earlier.
when under hood temps rise to 180-190 degrees the little bi metal sensor bends up and it allows full manifold vacuum to pull the heat riser motor, turning it on, that opens the flapper to the cold air setting and cools the intake air temperature since the motor no longer needs it when it is warmed up.
Possibly what happened was somebody took the air cleaner off and didn't know that hose was connected to the manifold tree, when they pulled up to remove the aircleaner base off the carb the hose popped off the sensor but was caught in the little handle on the back side of the aircleaner. so then somebody saw it was caught and pulled it off the intake tree but didn't know it disconnected underneath the air cleaner base.
there should be a bimetal heat sensor underneath the air cleaner base. its part of the base, if you lift it up and flip it over you will see it near the carburator hole on the passenger side
first it doesn't look like your aircleaner base as a AUX port on it which would be the drivers side, cause its a ram air base.
So the hose should go from the Manifold vacuum tree on the intake, to the bimetal sensor, then a second hose will go from the bimetal sensor to the vacuum motor on the heat riser.
if the first hose popped off the sensor then that would be a source of a decent size vacuum leak at idle.
the sensor will look like a round piece of bare metal with 2 tongs sticking out of it. the tongs are suppose to have 2 hoses connected to it.
this is the sensor that drives the flapper for the heat riser we talked about earlier.
when under hood temps rise to 180-190 degrees the little bi metal sensor bends up and it allows full manifold vacuum to pull the heat riser motor, turning it on, that opens the flapper to the cold air setting and cools the intake air temperature since the motor no longer needs it when it is warmed up.
Possibly what happened was somebody took the air cleaner off and didn't know that hose was connected to the manifold tree, when they pulled up to remove the aircleaner base off the carb the hose popped off the sensor but was caught in the little handle on the back side of the aircleaner. so then somebody saw it was caught and pulled it off the intake tree but didn't know it disconnected underneath the air cleaner base.
Everyone has given you great advice and mentioned things that need to be done but just thought I'd mention this as your issues sound similar to problems I was having a while ago.
You mentioned that the noise was on the left side of the engine compartment? Not sure if you mean when facing the car or when (as a parts store or mechanic think of it) sitting in the driver's seat. Anyway, check the short piece of rubber fuel line that goes from the steel line that comes in through the inner fender to the steel line that continues back out the inner fender along the front wheel well and then into the fuel pump.
The rubber hose on my car was old, had a hole in it that made it pull in air (the noise) and lose prime (stumbling and stall / not starting after sitting).
The attached pic shows the hose I mentioned. It has the shiny clamps and is located below the proportioning valve that is beside the master brake cylinder.
Hope it helps and will allow you to drive the car a bit while working on it.
You mentioned that the noise was on the left side of the engine compartment? Not sure if you mean when facing the car or when (as a parts store or mechanic think of it) sitting in the driver's seat. Anyway, check the short piece of rubber fuel line that goes from the steel line that comes in through the inner fender to the steel line that continues back out the inner fender along the front wheel well and then into the fuel pump.
The rubber hose on my car was old, had a hole in it that made it pull in air (the noise) and lose prime (stumbling and stall / not starting after sitting).
The attached pic shows the hose I mentioned. It has the shiny clamps and is located below the proportioning valve that is beside the master brake cylinder.
Hope it helps and will allow you to drive the car a bit while working on it.
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With a Holley carb that sounds like a blown power valve. The simplest way to prove the theory is to turn the idle misture screws in. It should stumble and try to die out, if turning them in has no effect replace the power valve.
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