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Discussion Starter · #1 · (Edited)
I have a 2001 7.3 the outside airtemp dosent seem to make a differance. When i start the engine for the first time of the day and try to drive it it will work ok for 1 to 2 minutes then it just shuts down like there is no fuel getting to it. The motor dose'nt die but i need to keep the throttle open all the way to keep it at about 800 rpm then slowley it will recover sometimes emmitting the blue white smoke. This will happen anywhere from one to three times. Once the engine is up to operating temp or it goes through its morning regiem it will be fine the rest of the day. No engine codes to referance and the batteries are new and so is the fuel filter. I need some ones thoughts as there is very little money to start just swapping stuff out. also the cam position sensor was changed out last year.
 

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Discussion Starter · #2 ·
Can nobody help me I see a few people have viewed it but no one has given any info ?
Is the problem that baffleing or difficult, I really need the help.
 

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If you start it up and let it idle for that 1-2 minutes does it shut down then? Or only when you're driving...?
 

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Discussion Starter · #4 ·
If i let it idle til operating temp it is fine and never dies. If i try to drive after i start up and accelerate to a normal speed never get above 20 or 25 MPH. it will chug and run rough with the throttle wide open and gradually come up in RPM. thenbog back down come up again and run so so til temp is up then fine. Some times it will die and i have to crank it quite a bit to get it to start. again it slowly gains RPM
 

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What is the temperature when you start it in the morning? It could be the exhaust back pressure valve working correctly, if the temperature is cold.
 

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Discussion Starter · #6 ·
it is in the 60s or 70 depending on the day. It has never done this before even on very cold mornings. this all just started 2 weeks ago this is the first bad issue i have had other than the CPS going out. when it does this the RPM drops to 800 it runs very rough for about 20 to 30 seconds then the RPM gradually comes up to where it will run and pull then drop back to 800 RPM for another 20 to 30 secs then run so so till it gets to temp then is fine the rest of the day even if i dont drive it again for several hours.
 

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it MIGHT be the MAF sensor. I had the same problem on my mustang when I got a bigger throttle body and fuel pressure regulater but didn't upgrate the MAF as well. The car would finally idle on it's own when it got to normal operating temp, otherwise I had to keep my foot on the pedal. It only happened in cold weather for me as well.
 

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I was looking for the answer for the same question. My 2000 7.3 is doing the same at startup in the morning. What I suspect is causing it to act this way is a lack of air. My understanding is the exhaust is used when the engine is cold to help warm up faster. It is as though the cold air intake is closing and the hot air is not opening thus starving the engine for air. This is just what I think is happening because I am not hearing the high air sound from the exhaust while it is warming up like it has done before. Could it be a valve malfunction in the intake system?
 

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I checked the Exhaust Back Pressure Valve tube for blockage but it came up clear. The problem I am having occurs in the morning when engine is cold and when it has sat at work for eight hours. Temperature outside makes no difference.:dunno:
 

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So I did what I had been trying not to do and took it to a repair shop.They pulled the codes and there were several. One was the MAPP and I was told for an additional $34 they would do some further testing to determine if the MAPP was at fault. I told them to go ahead and do the check. They replaced the MAPP and I paid and left. The next morning the same problem occurred. So I got back on the Internet and did some additional research. There were several similar occurrences listed and most were determined to be low oil level. It was time to change the oil anyway so I went ahead and performed the change. This morning there was no lack of power! From what I can figure, the low oil level creates a problem for one or more sensors that restrict the fuel flow when the engine is cold and the cold oil level is at its lowest. Once the engine warms and the oil expands and thins the fuel is supplied to the injectors as it should be. Problem solved. :D
 

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My bad! Thinking of the Mustang I forgot Diesels have MAP sensors not MAF :doh:
 

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Just to confirm that this was the problem I'm on day three with no return of the problem. There is nothing like the satisfaction of finding the answer of a problem like this.:thumb:
 
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