Yardsale
Well-Known Member
Wouldn't that be sweet?
2003 Sp Trac Intermittent Starting Problems
- Thread starter Harry H
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scott degroot
Well-Known Member
That would be very odd that a dirty IAC caused a no start condition. Even if the IAC were completely closed the engine should still run at base idle which is about 450-500 rpm's. They usually will stall though however they will normally still start. If you tried giving it gas while cranking and it still didn't start then you can eliminate the IAC as a source of the problem.
I1tech: I'm not sure if you'd call it a start, but usually what it would do is fire and immediately stumble and quit, or it would stumble and run very rough (I mean really rough) for a few seconds and then quit. I have always started the truck without giving it any gas, but a few of the times on start when it fired, but was running really rough I gave it some gas and it immediately quit.
scott degroot
Well-Known Member
While I am hopeful that the dirty IAC was your issue, based on your last description I am skeptical.
Just an update. Still starting OK today, but seemed to not start as smoothly today.
Wanted to mention something else that I had forgotten about that probably isn't related, but thought I would mention it anyway. When I shut the engine off I get a strange noise a few seconds later. It has been doing this for quite a while (at least year) and I really didn't think it was a big deal. Possibly related to the starting problem?? Any ideas what it might be?
Seems to be coming from the drivers side fuel rail / coil area.
I made a short video. The sound is at the very end of the video about a second or so after the engine is shut off.
Wanted to mention something else that I had forgotten about that probably isn't related, but thought I would mention it anyway. When I shut the engine off I get a strange noise a few seconds later. It has been doing this for quite a while (at least year) and I really didn't think it was a big deal. Possibly related to the starting problem?? Any ideas what it might be?
Seems to be coming from the drivers side fuel rail / coil area.
I made a short video. The sound is at the very end of the video about a second or so after the engine is shut off.
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Mark Price 2
Active Member
That is your EGR Vacuum Solenoid/EVR(egr vacuum regulator)Solenoid making the sound after you cut the engine off. I have heard that "tooting"
sound on my ST as well. I don't believe it to be any kind of issue. I have tested my entire EGR system. All good.
It's the item with the round cap (tiny hole in center, 6 "teeth" and an electrical connector) on it in between the EGR Valve(thing with the vacuum nipple on top) and Coil Pack.
Try giving it a spin. It spins freely. It may quiet it down or change in tone. That worked for mine IIRC or it just stopped tooting by itself. I cannot recall, sorry. I just ran outside and checked. It does not toot any longer but it definitely makes a slight sound/vibration 2 seconds after shutting the engine down. Barely.
That being said...my ST starts and runs perfectly and I don't believe this is your issue. BUT, a faulty item in the egr system can cause stalling and rough idling. (not so sure about a cranking no start though) If you want to test the entire EGR system(egr passages, dpfe sensor, evr, wiring, egr vacuum hoses, and pcm driver in one easy test, watch this video.
Video: Ford EGR Flow Testing by ScannerDanner (if you don't have a scan tool...t-pin top wire(signal wire) on dpfe sensor to read dpfe voltage on a volt meter while doing the test)
(actually watch ALL his EGR videos. Search "ScannerDanner EGR" They are great! IF you watch all of them you will be a EGR master by the end)
sound on my ST as well. I don't believe it to be any kind of issue. I have tested my entire EGR system. All good. It's the item with the round cap (tiny hole in center, 6 "teeth" and an electrical connector) on it in between the EGR Valve(thing with the vacuum nipple on top) and Coil Pack.
Try giving it a spin. It spins freely. It may quiet it down or change in tone. That worked for mine IIRC or it just stopped tooting by itself. I cannot recall, sorry. I just ran outside and checked. It does not toot any longer but it definitely makes a slight sound/vibration 2 seconds after shutting the engine down. Barely.
That being said...my ST starts and runs perfectly and I don't believe this is your issue. BUT, a faulty item in the egr system can cause stalling and rough idling. (not so sure about a cranking no start though) If you want to test the entire EGR system(egr passages, dpfe sensor, evr, wiring, egr vacuum hoses, and pcm driver in one easy test, watch this video.
Video: Ford EGR Flow Testing by ScannerDanner (if you don't have a scan tool...t-pin top wire(signal wire) on dpfe sensor to read dpfe voltage on a volt meter while doing the test)
(actually watch ALL his EGR videos. Search "ScannerDanner EGR" They are great! IF you watch all of them you will be a EGR master by the end)
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Mark Price 2
Active Member
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Mark Price 2
Active Member
:supercool:
Sorin W
Member
it's clearly a temperature related issue, my trac (2001 with 340,000 miles) has this issue as well and after digging I found this article:
"Magnetic crankshaft position sensors are fairly simple and reliable, but the internal windings can sometimes open and kill the crank signal if the sensor gets too hot. If the engine has a magnetic crank sensor, you can test it with an ohmmeter to see if the resistance is within specifications. But even if the sensor tests ?good,? it may still cause trouble. We?ve seen certain crank sensors that measure within specifications when tested cold with an ohmmeter, but suddenly go wide open if the sensor gets hotter than 200 to 220? F. One minute it?s working fine producing a good signal, and the next it goes dead and causes the engine to stall. If an overheated crank sensor is causing a stalling problem, the engine may not restart until it sits awhile and the sensor cools down."
The link has the part (only $14.99 and wires another $6.99) and I'll give it a try myself too
"Magnetic crankshaft position sensors are fairly simple and reliable, but the internal windings can sometimes open and kill the crank signal if the sensor gets too hot. If the engine has a magnetic crank sensor, you can test it with an ohmmeter to see if the resistance is within specifications. But even if the sensor tests ?good,? it may still cause trouble. We?ve seen certain crank sensors that measure within specifications when tested cold with an ohmmeter, but suddenly go wide open if the sensor gets hotter than 200 to 220? F. One minute it?s working fine producing a good signal, and the next it goes dead and causes the engine to stall. If an overheated crank sensor is causing a stalling problem, the engine may not restart until it sits awhile and the sensor cools down."
The link has the part (only $14.99 and wires another $6.99) and I'll give it a try myself too
Well, I cleaned the IAC about 9-10 days ago and it seemed to fix the problem, but I still wasn't convinced, so I took it in to the Ford dealer and had them hook it up to their machine. They said it needs a new fuel pump (just under $1000 for them to replace it). I know the fuel pump has been coming on, because I can hear it, but maybe it's weak. So, I'm going to throw a guess out there and say it was a combination of IAC and a weak fuel pump. I could be wrong, but at this point I've started the truck 25-30 times since cleaning the IAC and it has started every time, so I'm happy. I also ordered a new fuel pump from RockAuto and it just showed up today. I also put in new plugs and wires a few days ago. If I still have a problem in the future, then the crank sensor would be a simple and inexpensive thing to try.
For now, I'm looking forward to installing the new pump in the next day or two. Got to burn off a little more fuel out of the tank first :grin:
For now, I'm looking forward to installing the new pump in the next day or two. Got to burn off a little more fuel out of the tank first :grin:
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Dreman
Well-Known Member
Believe me, it's a LOT easier with the tank almost empty!
Hey David,
Thanks for documenting your pump change in the Projects section! It'll make it a lot easier for me to do the change.
I did some checking around and didn't come across a pump with a 5 pin connector. I haven't removed my old one yet, but I'm assuming it has a 5 pin. I spoke with someone locally here who says the 4 pin superseded the 5 pin and will plug into and work with the old 5 pin connector. I also read in an Explorer forum that the 5th wire doesn't go anywhere once it gets to the pump, so I went ahead an ordered a pump with the 4 pin connector. I'll report back here what I find out, so it may help out someone else needing to order a new pump.
Thanks for documenting your pump change in the Projects section! It'll make it a lot easier for me to do the change.
I did some checking around and didn't come across a pump with a 5 pin connector. I haven't removed my old one yet, but I'm assuming it has a 5 pin. I spoke with someone locally here who says the 4 pin superseded the 5 pin and will plug into and work with the old 5 pin connector. I also read in an Explorer forum that the 5th wire doesn't go anywhere once it gets to the pump, so I went ahead an ordered a pump with the 4 pin connector. I'll report back here what I find out, so it may help out someone else needing to order a new pump.
Sorin W
Member
I don't know if your issue happens only when the engine is still warm, that is my case. Mine will always start perfect in the morning or after a few hours after the truck was driven. Please check the discussion at the following link:
http://www.twoguysgarage.com/forum/showthread.php?t=8434
The guy solved exactly the issue I'm having by replacing the coolant temperature sensor and TPS sensor, but he's almost certain to be the coolant temperature sensor that took care of the problem. Watch the guy in the youtube link below that explains why that sensor causes this problem, mainly because the temperature reading tells the ECU how much fuel to dump in the cylinder if its a cold or hot engine start.
http://www.twoguysgarage.com/forum/showthread.php?t=8434
The guy solved exactly the issue I'm having by replacing the coolant temperature sensor and TPS sensor, but he's almost certain to be the coolant temperature sensor that took care of the problem. Watch the guy in the youtube link below that explains why that sensor causes this problem, mainly because the temperature reading tells the ECU how much fuel to dump in the cylinder if its a cold or hot engine start.
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Sorin,
I'm pretty sure my problem is not a temperature related issue. You would think that, by letting it set for about 30 minutes and correcting itself, the problem would have to be something in the engine cooling down and correcting itself. The only problem with that theory is that sometimes it would do the "no start" thing when the truck was in my driveway and hadn't been run for a couple of days. I would continue to try and start it (cold) and it was a no go unless I let it set for about 30 minutes and then it would start right up (almost like a vapor lock or something like that). It would also do the same thing sometimes when it was hot. I know it sounds strange, but that was what was going on.
For now I'm sticking with the dirty IAC and possibly fuel pump as I still haven't had a "no start" since cleaning the IAC.
Thanks for the input though! That's an interesting video and good info on the coolant temp sensor. I wasn't aware that the sensor sends info to the ECU to help out with the mixture.
I'm pretty sure my problem is not a temperature related issue. You would think that, by letting it set for about 30 minutes and correcting itself, the problem would have to be something in the engine cooling down and correcting itself. The only problem with that theory is that sometimes it would do the "no start" thing when the truck was in my driveway and hadn't been run for a couple of days. I would continue to try and start it (cold) and it was a no go unless I let it set for about 30 minutes and then it would start right up (almost like a vapor lock or something like that). It would also do the same thing sometimes when it was hot. I know it sounds strange, but that was what was going on.
For now I'm sticking with the dirty IAC and possibly fuel pump as I still haven't had a "no start" since cleaning the IAC.
Thanks for the input though! That's an interesting video and good info on the coolant temp sensor. I wasn't aware that the sensor sends info to the ECU to help out with the mixture.
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Dean Hedin
Active Member
My I had intermittent starting failures like this. It was the fuel pump.
Got the new fuel pump installed yesterday. Don't know if I can tell any difference yet, and I'm still convinced the dirty IAC was at least part of the problem.
Installing the new pump was a challenge. For me the most difficult part was reaching up and disconnecting the hose from the filler neck where it attaches to the tank. Very limited room and the hose was very tight (molded) to the inlet nipple. I struggled for about 2 hours just trying to get it disconnected. The other thing that surprised me, was after removing the tank, that I had a 4 pin connector. I expected it to be 5 pin, so can't help with compatibility of the 4 and 5 pin connectors.
Thanks again to everyone for the feedback and dreman for documenting the pump change in the projects section.
Installing the new pump was a challenge. For me the most difficult part was reaching up and disconnecting the hose from the filler neck where it attaches to the tank. Very limited room and the hose was very tight (molded) to the inlet nipple. I struggled for about 2 hours just trying to get it disconnected. The other thing that surprised me, was after removing the tank, that I had a 4 pin connector. I expected it to be 5 pin, so can't help with compatibility of the 4 and 5 pin connectors.
Thanks again to everyone for the feedback and dreman for documenting the pump change in the projects section.
