I don't know about Ford's but that idle-air bypass valve you mention might be it. I had the exact same symptom crop up on a 5.2 Dodge after sitting for awhile (poor cold idle, surging, and then ran fine after it warmed up). I believe the WD-40 I sprayed in there unstuck the air valve. That is all I did, and it has been fine ever since (couple months).
Can't seem to resolve this problem..please advise
- Thread starter demarpaint
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Thanks,
I replaced the idle air bi-pass valve, cleaned all carbon out, there was very little.
My understanding is the Coolant Temp Sensor, and Air Charge Sensor have a lot to do with Start up, and running as well. Since the CTS is new, that leaves the ACT. LOL
I just went out and tried turning the key on and off several times without starting it up to pressurize the fuel system to see if that made any difference. It didn't.
The ACT looks like another PIA to change, but I am running out of options here.
I had it to a mechanic for a diagnosis, and he is clueless.
I think the key to this problem is the lack of power when cold. I remember years ago on the old carbed engines, the choke pull off messing up causing the exact same problem. A simple turn of a sping was all it took to fix that. It's whatever sensor/s that is responsible for the cold start on the 4.9L that's messing this thing up.
I appreciate all the help! I am determined to reslove this one way or another!
Frank D
I replaced the idle air bi-pass valve, cleaned all carbon out, there was very little.
My understanding is the Coolant Temp Sensor, and Air Charge Sensor have a lot to do with Start up, and running as well. Since the CTS is new, that leaves the ACT. LOL
I just went out and tried turning the key on and off several times without starting it up to pressurize the fuel system to see if that made any difference. It didn't.
The ACT looks like another PIA to change, but I am running out of options here.
I had it to a mechanic for a diagnosis, and he is clueless.
I think the key to this problem is the lack of power when cold. I remember years ago on the old carbed engines, the choke pull off messing up causing the exact same problem. A simple turn of a sping was all it took to fix that. It's whatever sensor/s that is responsible for the cold start on the 4.9L that's messing this thing up.
I appreciate all the help! I am determined to reslove this one way or another!
Frank D
Just had another look, there are no sensors on the Throttle body other that the Idle air bi-pass valve and the TPS which have been replaced.
I am going to have a look at the ACT sensor next.
This trouble shooting with out any codes is tough.
Thanks
Frank D
[ January 03, 2006, 01:05 PM: Message edited by: demarpaint ]
I am going to have a look at the ACT sensor next.
This trouble shooting with out any codes is tough.
Thanks
Frank D
[ January 03, 2006, 01:05 PM: Message edited by: demarpaint ]
Most recent update. New parts: IAC, TPS, CTS, ATS, O2 Sensor, Plugs,(which were perfect), cap, wires, rotor, TFI, Thermostat as per factory specs. Parts were not replaced in the above order.
After changing the ATS and re-cleaning the Throttle Body which was clean (this was the most recent job). It now starts and stalls once, runs for a minute and stalls as if it were running out of gas. It will stall if you try to move it without allowing a few minutes run time, and totally lacks power when cold.
Once warm it runs fine and has a lot of power, will start right back up once warm.
No vacuum leaks of any kind.
I'm getting there?
Thanks
Frank D
After changing the ATS and re-cleaning the Throttle Body which was clean (this was the most recent job). It now starts and stalls once, runs for a minute and stalls as if it were running out of gas. It will stall if you try to move it without allowing a few minutes run time, and totally lacks power when cold.
Once warm it runs fine and has a lot of power, will start right back up once warm.
No vacuum leaks of any kind.
I'm getting there?
Thanks
Frank D
Still sounds like a CTS to me. Do you suppose you replaced a bad one with a bad one? Usually you can check the resistance of those things with an ohm meter to see if they are about right but I don't know the readings for a Ford.
Frank, there may be a code stored even though the CEL isn't on. If so, the code will give clues as to where the problem is. Here's a site that tells how to run a self-test on the stored codes.
Ford Self-Test
(The rest of this site is also a good read on Ford fuel injection.)
The only thing I can think of that you haven't checked/changed is the MAP sensor (I assume this is a speed density engine because of the model?). The MAP is located on the driver's side firewall, and has a vacuum hose and electrical connector attached. First check for cracks and a secure attachment in the vacuum hose.....
TLR
Ford Self-Test
(The rest of this site is also a good read on Ford fuel injection.)
The only thing I can think of that you haven't checked/changed is the MAP sensor (I assume this is a speed density engine because of the model?). The MAP is located on the driver's side firewall, and has a vacuum hose and electrical connector attached. First check for cracks and a secure attachment in the vacuum hose.....
TLR
I dont know if applicable. but my wifes 2000 chevy malibu did that. when cold you start it. it would die. start it again and die. but after it was warm it ran fine. took it to a chevy dealership they said there is nothing wrong. and after the 3rd time they told my wife she just didnt know how to start a fuel injected car. well I took it to another dealership and less than 15 min they called me and said we think we found the prob. the fuel filter is twice as heavy as it should be.
they relaced it and never had a prob yet. been over 3 years now.
so you might want to try replacing the fuel filter. after all cant hurt and alot cheaper than all those sensors.
they relaced it and never had a prob yet. been over 3 years now.
so you might want to try replacing the fuel filter. after all cant hurt and alot cheaper than all those sensors.
Checking the fuel pressure and delivery rate wouldn't be a bad idea.
Thanks,
It would suck to have replaced a bad Sensor, with a new bad Sensor, but anything is possible. The MAP sensor was replaced early on in this whole mess. I guess I am now going to have to check every sensor individually. I am showing no codes. Odd that nothing I replaced did anything to greatly improve the situation.
At this point the only other parts to change are the Fuel Pump, and the EGR valve. Everything else has been replaced! I changed the fuel filter, I do every year, it did nothing.
I am now thinking fuel pump, but there are no signs of problems running or climbing inclines. I keyed the ignition on and off 5 times to pressurize the system to see if that helped with the start stall issue. It didn't.
Problem with being a back yard mechanic is by the time I go out and buy the tools necessary to check Fuel Pressure and Delivery rate it would be cheaper to change the pump. That is why I tried the primative test mentioned above, but obviously its not giving me any real numbers to go by.
Thanks, all help is greatly appreciated!
Frank D
It would suck to have replaced a bad Sensor, with a new bad Sensor, but anything is possible. The MAP sensor was replaced early on in this whole mess. I guess I am now going to have to check every sensor individually. I am showing no codes. Odd that nothing I replaced did anything to greatly improve the situation.
At this point the only other parts to change are the Fuel Pump, and the EGR valve. Everything else has been replaced! I changed the fuel filter, I do every year, it did nothing.
I am now thinking fuel pump, but there are no signs of problems running or climbing inclines. I keyed the ignition on and off 5 times to pressurize the system to see if that helped with the start stall issue. It didn't.
Problem with being a back yard mechanic is by the time I go out and buy the tools necessary to check Fuel Pressure and Delivery rate it would be cheaper to change the pump. That is why I tried the primative test mentioned above, but obviously its not giving me any real numbers to go by.
Thanks, all help is greatly appreciated!
Frank D
Not sure if this observation helps or not. I had the air cleaner off, but the intake hoses that go to the throttle body were connected. I had placed a cover over them to keep junk out, and accidentally started the van. It started perfectly and began to suck the covers into the intake tubes going to the throttle body. No damage done, but the van started perfectly with these make shift covers that I put on to keep junk out while I was away from the van.
These covers cut the flow of air down tremendously allowing a very rich mix is my guess. Any ideas?
Thanks, all replies are greatly appreciated.
Frank D
These covers cut the flow of air down tremendously allowing a very rich mix is my guess. Any ideas?
Thanks, all replies are greatly appreciated.
Frank D
yo ucan always disconnect the fuel line going in to the fuel rail. put the hose in a bucket. have some one turn the key on and if it sputters then yo uknow its in your fuel system. if yo uget good flow. then the pump is fine. its cheaper than buying all that stuff to ck fuel pressure.
Will have to give that a try, looks easy enough to do.
Thanks
Thanks
The CTS (coolant temperature sensor) and the ACT (air charge temperature sensor) have the same resistance/temperature curve so if they're at the same temperature, they should read the same resistance. This can be checked after the vehicle has been sitting long enough that both sensors are at ambient temp.
The MAP sensor should be outputting about 158Hz with the engine off but the key on. You can use a multimeter with a frequency counter to test it.
If it has a MAF sensor, then it will still have a BAP sensor and the BAP sensor should also output about 158Hz (doesn't matter if the engine is off or on).
The MAP sensor should be outputting about 158Hz with the engine off but the key on. You can use a multimeter with a frequency counter to test it.
If it has a MAF sensor, then it will still have a BAP sensor and the BAP sensor should also output about 158Hz (doesn't matter if the engine is off or on).
Just out of curiosity, wouldn't a bad fuel pump show some kind of symptoms when driving? I've had them go bad in other vehicles and there always was either a no run condition, or lack of power when under load or at high speeds. I have none of these problems.
Once again thanks for the replies,
Frank D
Once again thanks for the replies,
Frank D
I would guess not all of them goes out 100 percent all the time.
is your fuel filter on the fuel pump or is it on your frame rail? if on your frame rail then you might have some junk that got sucked up in to it and floating around in the pump and might be clogging and unclogging. sorry I cant help yo umore. but I dont know much about stuff like this. just going by what I have heard other poeple posted in dakota boards.
I hope you get the prob solved. sounds like you sunk alot of time and money in this vehicle.
is your fuel filter on the fuel pump or is it on your frame rail? if on your frame rail then you might have some junk that got sucked up in to it and floating around in the pump and might be clogging and unclogging. sorry I cant help yo umore. but I dont know much about stuff like this. just going by what I have heard other poeple posted in dakota boards.
I hope you get the prob solved. sounds like you sunk alot of time and money in this vehicle.
demarpaint
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"Just out of curiosity, wouldn't a bad fuel pump show some kind of symptoms when driving? I've had them go bad in other vehicles and there always was either a no run condition, or lack of power when under load or at high speeds. I have none of these problems."
Fuel pumps can have different concerns. A pump with an actual pumping problem will cause lean operation on accel (hesitation/lack of power)or engine shutdown just because the fuel volume cannot keep up with airflow. Sometimes the "leanout" feels just like a bad MAF if so equipped. Common during the summer months. Can be due to worn pump components or bad electrical windings/high resistence (proportional to heat) in the brushes of the pump motor.
A bad fuel pump check valve will show itself by excessive crank times and/or ~ 5-30 seconds of rough idle on cold startup. The engine idles rough until the line/injector rail/injectors are bled.
The only real way to diag this is a fuel pressure gauge. Cold start,Key on engine off- fuel pressure should climb to top of pressure spec and maintain within 5 psi of that pressure for ~ 2 minutes after the relay clicks off. Codewise, a 172/176 lean code will be a tipoff to a weak pump, a 556 or a 54X fuel pump circuit falure secondary code will steer you toward a faulty relay.
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"Just out of curiosity, wouldn't a bad fuel pump show some kind of symptoms when driving? I've had them go bad in other vehicles and there always was either a no run condition, or lack of power when under load or at high speeds. I have none of these problems."
Fuel pumps can have different concerns. A pump with an actual pumping problem will cause lean operation on accel (hesitation/lack of power)or engine shutdown just because the fuel volume cannot keep up with airflow. Sometimes the "leanout" feels just like a bad MAF if so equipped. Common during the summer months. Can be due to worn pump components or bad electrical windings/high resistence (proportional to heat) in the brushes of the pump motor.
A bad fuel pump check valve will show itself by excessive crank times and/or ~ 5-30 seconds of rough idle on cold startup. The engine idles rough until the line/injector rail/injectors are bled.
The only real way to diag this is a fuel pressure gauge. Cold start,Key on engine off- fuel pressure should climb to top of pressure spec and maintain within 5 psi of that pressure for ~ 2 minutes after the relay clicks off. Codewise, a 172/176 lean code will be a tipoff to a weak pump, a 556 or a 54X fuel pump circuit falure secondary code will steer you toward a faulty relay.
Did anyone mention the pcv valve/crankcase breather? (not sure which this engine has). Could be a simple $5 part.
Thanks for the replies.
Dark Jedi : The FP is on the rail before the fuel filter so it could have junk inside it, something worth checking.
Punisher: Thanks for the info, I have no codes showing, but I do have a new FP I friend had given me when he sold his E-150, its NIB andit might pay for me to give it a try. I got it the other day, and was hoping to hear it could be the FP before I put it in. As mentioned I have no way to check pressure, other than letting it pump into a can. Keying on and off 5 times before starting made no difference.
Sebring01, PCV valve, breather and air filter wasn't mentioned but it was changed when I tuned the van up, as part of a major tune up.
Thanks to all of you who replied.
Frank D
Dark Jedi : The FP is on the rail before the fuel filter so it could have junk inside it, something worth checking.
Punisher: Thanks for the info, I have no codes showing, but I do have a new FP I friend had given me when he sold his E-150, its NIB andit might pay for me to give it a try. I got it the other day, and was hoping to hear it could be the FP before I put it in. As mentioned I have no way to check pressure, other than letting it pump into a can. Keying on and off 5 times before starting made no difference.
Sebring01, PCV valve, breather and air filter wasn't mentioned but it was changed when I tuned the van up, as part of a major tune up.
Thanks to all of you who replied.
Frank D
I haven't had much time to work on this van this past week. I have read thru these replies several times, and remember an observation I made, and was wondering if it means anything?
When I changed the fuel filter, which sits on the rail in front of the fuel pump, I remember removing it and the fuel just leaked out slightly. There was no pressure, no hissing, nothing. I did this about 30 minutes after I shut the van off, and did not relieve fuel pressure in any way. The gas cap was on, I just removed the clips, loosened the clamp that holds the filter and took it off.
Aren't these systems under pressure, or does it lose pressure from sitting the 30 minutes?
Thanks again,
Frank D
When I changed the fuel filter, which sits on the rail in front of the fuel pump, I remember removing it and the fuel just leaked out slightly. There was no pressure, no hissing, nothing. I did this about 30 minutes after I shut the van off, and did not relieve fuel pressure in any way. The gas cap was on, I just removed the clips, loosened the clamp that holds the filter and took it off.
Aren't these systems under pressure, or does it lose pressure from sitting the 30 minutes?
Thanks again,
Frank D
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