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08 GT starts but won't stay running

8K views 26 replies 11 participants last post by  pancaken 
#1 ·
Hello,


Last weekend my 08 GT started with a bad idle and then died on us while we were 250 miles away. I was able to get it started again and we made it home but since then it will intermittently start and run ok and idle just fine until I rev it up and bit and then it will sputter and die at idle.
After that it will only fire up but not continue running, giving it gas does nothing.
What I've tried:

Edited:


1) Cleaned the throttle body
2) Replaced the MAS
3) Replaced the fuel filter
4) Replaced the fuel pump
5) Replaced the Throttle body motor
6) Replaced the fuel rail pressure sensor due to a CEL, CEL went out after.
7) Replaced the TPS

I've run out of ideas, there are no codes and once in a while it'll act like all is ok for a while.


Help?
 
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#3 ·
Yes I did, I forgot to add that.
Also, a couple of weeks ago I got a CEL that told me my fuel rail pressure sensor was bad even though it ran just fine.
I replaced the sensor and the CEL went away immediately and has until this last weekend. The car fires up like it wants to run, it just dies right away.
 
#4 ·
It's might be an electrical problem or a vacuum leak. Ignition coil, wires, spark plugs, etc. It's an eleven year old car so these things go eventually. Check all the hoses to make sure they are connected and not leaking. Are the plug wires arcing? Run the engine and lower the hood a bit to keep the light out and see if any of the wires arc.

Pete
 
#6 ·
Do you have a scanner that can read diagnostic data and codes? If so that could be helpful. There are a number of things you could check with that, but my first thought is fuel pressure.

I would suggest checking the spark plugs just to make sure they are fine. I replaced mine half a year ago and then in the last month I had been getting a hesitation while accelerating. I checked everything else first assuming the plugs were fine, but when I checked them yesterday, one was broken and I had been running on 7 cylinders for the last month. That at least is an easy check.

Another thing you can check is fuel injectors. The easy checks for those without removing them are using a stethoscope or something to transmit sound and listen for a steady clicking while the engine is running. You can then check the resistance of each one with a multimeter to see if one is way off.
 
#8 ·
What fuel rail pressure sensor did you install? Aftermarket or Ford OEM? Can you monitor live data? If so, what is the fuel rail pressure pre-igntion?
 
#9 ·
Have you checked the fuel pump driver module?
 
#13 ·
It should be in the spare tire well, aft on the drivers side. There is a wire harness that connects to it, and the view of it,when looking straight down, is blocked by piece of plastic.
 
#14 ·
Yep, I found it and replaced it. $112 for a Dorman replacement at AutoZone. No go, the car still fires up strong and dies right away. On the first start I was able to give it some gas and make it idle like crap for a bit before dying.
After that it just starts and dies. This is incredibly frustrating...
 
#15 ·
Have you had the catalytic convertor checked? If it`s plugged the car will act like that.
 
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#16 ·
I haven't. The one thing I haven't mentioned is that this all happened after a particular heavy rainstorm that we got caught in.
Not sure if that matters because it drove just fine in the rain and didn't start this until i went to move it much later.
 
#18 ·
Sounds to me like your sjb box got wet in rainstorm and messed it up. It’s a common problem on 2005-09 cars. It’s behind the kick panel on passenger side of the car. Open it up and see if anything is damp. If it is I bet that’s your problem.


Sent from my iPad using Tapatalk
 
#20 ·
So this morning I went out and just tried to start the car, it fired right up, rev'd up and down oddly just for a couple of seconds and smoothed out. I was then able to rev the engine just fine. All seemed normal.
So I shut it down and here we are again. It will just fire up and die.

I bypassed that switch, it had no effect.
 
#21 ·
I still have that nagging feeling that the problem is related to the fuel pump. Check the FP relay if you haven't already, and see if there's any sign of burn marks on the terminals in the underhood fusebox.
 
#22 ·
I looked at the relay, no burn marks or any obvious signs of failure. I tried swapping it out with another of the same size as well.
Question: I replaced the drivers side fuel pump, as I look to the other side of the tank on passengers side there's that same round black runner cover, when I take that off there's an electrical connection going to it
but not a fuel line feed. What's on that side of the tank?

So I went and spoke with a mechanic today, a really good one. He suggested I spray brake cleaner in to the intake to see if the car will run on it. It will just as long as I keep spraying it in.
I haven't been able to get back to him but I wanted to let people here know. With a new pump assembly and pump module already in the car does this mean the issue is with the ECM?
 
#24 ·
When fuel injection became the way to go, Ford used an impact sensor, to shut off the fuel pump, that had to be reset after a collision,, or major pothole. What are they using today? GM used to use an oil pressure switch to turn the fuel pump on.


Just throwing stuff out there.
 
#26 · (Edited)
So this morning after letting it sit for a couple of days I went out and tried to start it and it fired right up, bit of a rough idle at first but it smoothed out. I then let it run for five or six minutes while went around and started wiggling wires, etc to see if I could make it stall.
Eventually with me doing nothing at all is stalled out on its own. Now it just starts and dies again.


I didn't do the sender underneath the passenger side of the tank, could this be the issue??



THIS MAY BE FIXED:

A few days ago I got a P0193 code thrown. Fuel rail pressure sensor. I went to AutoZone and got a new one, put in on and the code went out.
Today out desperation I put the old one back on and it FIRED RIGHT UP. I let it idle for a while and shut off and started it again. So next I took it down the road, no issues. Could be that AutoZone sold me the wrong/bad part?? Looks like it $500 in parts later.

 
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