how do you check fuel pressure on these cars? do you tee into the return line? i need to see if the fuel pump is dying out making the car stall. car will start and run fine when cold but when it warms up it bogs down and dies. it will start right back up but then wont stay running. if i come back to it the next day same thing. it will start and run for a few minutes then wont stay running. no codes so really what else can it be at this point? it does not seem like its part of the ignition (key) because it does bog down and hesitate before it dies. anyone have suggestions? thanks

 

What are your mods first off?

Have you done a boost leak test?

Any vacuum lines disconnected for the EGR?

What is the spark plug gap set at and are they fresh plugs?

Is the BOV recirculated or vta?

When was the car tuned last?

 

its not my car and im a mustang guy so you might have to work with me on this as far as mods go. as far as i know its stock block and head, stock turbo. i dont know if the injectors are stock. had to be a few years since it was tuned. its got all the new piping, new intercooler, down pipe. the bov looks like it is recirculated. the plugs are the pre gapped ngk's. they are the same ones that came out of it so thats what i put back in. you might be onto something with with the boost leak. the car actually sat for over a year with a spun rod bearing. i just finished getting everything back together and had it up and running. i put around 10 miles on it driving around the block and everything was good. i went to the main road and when i hit 3rd the intercooler pipe popped off. thats when this started happening. i got everything tightened back up and started cruising around the block. made it around a few times but now its giving me this problem. its still has egr and i dont hear any vacuum leaks.

 

why would the car run fine for a few minutes then start acting up after it warms up. does the computer do something different with the boost solenoid when the car heats up? if it were a boost leak wouldn't it be a problem from the first second you start the car. shouldn't be a difference right? i just looked under the car and everything is tight

 

also wanted to add i hear the fuel pump prime when the car dies. does that sound right? should it be doing anything?

 

Does the car stay running if you give it gas? Do you have anything to pull data with?

 

the plugs you have may not be set to the correct gap i would check what they are. i had to close the gap on the plugs i bought. also since the car was sitting for a year did you replace the fuel filter? it may be clogged. you also did not mention what gas you are currently running the car with? im just assuming you have new gas in there correct?

 

Does it stay running when you unlplug the maf?
Any codes?
Does it say running with foot on the throttle?

My car was starting and dying a couple seconds after this whole week. I gave it one more look over/check and found my fuel relay resistor box wasnt plugged in all the way and had come loose. The car would run only with the maf unplugged and would die when i plugged it in. It would also die if i gave it throttle with the maf plugged in. Also it might be the cam sensor... i replaced mine thinking that was my issue because all signs pointed to that.

 

car will still die if i try to keep it running by giving it some throttle. drained the tank. running fresh 93. i doubt its the plugs. the car ran fine for around 10 miles before this started happening. it still starts fine and runs fine until it warms up. it will occasionally throw the cam and crank sensor code but some else mentioned those can come up when the engine stalls regardless. i did change the cam sensor and it still does the same thing and will occasionally throw those codes again so i doubt that its a bad sensor. i can change the crank sensor but i dont think it will help at this point. the car stalled a few times today without throwing any codes. i also read these cars dont have an inline fuel filter. i definitely did not change it if they do. im going to tee into the fuel return tomorrow after work and see if the fuel pressure drops off before it happens. that will at least tell me where to look next. thanks for the suggestions. keep them coming.

 

if it starts fine your crank sensor is ok... your tps might be off, log that... could be so many different things!

 

no way to log tps. if it was out of range wouldn't it throw a code? really can only be loosing fuel or spark. just need to figure out why.

 

Your symptoms are of a crank or cam sensor issue. You need to verify that they are good sensors and that the wiring to them is good. If you have a multi-meter and test light this would be the time to break it out. What is the year of the vehicle? You need to verify your power and grounds. Crank/Cam sensors tend to fail when warmed up and will cause the car to randomly stall. Still should verify wiring integrity.

 

should throw a code every time if it were the sensor/wiring malfunctioning? today it happened multiple times without throwing the codes. i changed the cam sensor yesterday just so i can rule that out. i have a new crank sensor. i can see if thats it this weekend when i have a few hours to go at it. at this point im really hoping its either the crank sensor or fuel pump. that would make the most sense to me. unless there is something else killing the spark i dont see what else it could be. if it were any sensor it should throw a code right? if its not a sensor or the computer cutting fuel or spark it has to be a fuel supply issue. compression is not the problem.

 

its an 03 btw

 

faulty fuel pump relay maybe... like stated check everything with a multi meter.