Fuel, Spark,and No START!!

D

Drews93fox

Member
Feb 22, 2010
140
0
17
Danville, Iowa
#1
So i'm having a prob;em when my car is warm after driving, It will not start. I pulled a plug and have very good spark. I took off the hose that runs to the front of the car from the tank, lots of fuel. The motor turns over like a champ so im thinking that it is some sensor. The car has a twin turbo set up on it and it has alot of heat on top, I ordered some turbo covers for them so i also think that it could be vapor lock? Its a 93' LX with 30lb injectors, 255lph fuel pump, 75mm throttle body and mass air meter, and msd ignition 6al box and coil. Please help it really sucks when i can only drive it once in a night.

Also when it is completely cold it starts right up not a problem at all, so im really sure that it has something to do with the heat. Thanks everyone
 
#2
Drews93fox said:
So i'm having a prob;em when my car is warm after driving, It will not start. I pulled a plug and have very good spark. I took off the hose that runs to the front of the car from the tank, lots of fuel. The motor turns over like a champ so im thinking that it is some sensor. The car has a twin turbo set up on it and it has alot of heat on top, I ordered some turbo covers for them so i also think that it could be vapor lock? Its a 93' LX with 30lb injectors, 255lph fuel pump, 75mm throttle body and mass air meter, and msd ignition 6al box and coil. Please help it really sucks when i can only drive it once in a night.

Also when it is completely cold it starts right up not a problem at all, so im really sure that it has something to do with the heat. Thanks everyone
Click to expand...

Vapor lock could happen with all of that turbo heat, but from what I understand about vapor lock, the car would start to run badly when it heated up.

However, in my humble opinion, I could see that happening with your mustang. Speculating, but after you kill the car the fuel starts to flow back slowly and pressure decreases at the motor. As pressure decreases the likelyhood of that gas turning to vapor in the rails would increase. So if you have hot rails with vapor in them, it would take time for the turbos and rails to cool down. :shrug:

Just my 2 cents, but if you have fuel, air and spark... And twin turbos create an enormous amount of heat.
 
#3
Strype said:
Vapor lock could happen with all of that turbo heat, but from what I understand about vapor lock, the car would start to run badly when it heated up.

However, in my humble opinion, I could see that happening with your mustang. Speculating, but after you kill the car the fuel starts to flow back slowly and pressure decreases at the motor. As pressure decreases the likelyhood of that gas turning to vapor in the rails would increase. So if you have hot rails with vapor in them, it would take time for the turbos and rails to cool down. :shrug:

Just my 2 cents, but if you have fuel, air and spark... And twin turbos create an enormous amount of heat.
Click to expand...

I agree with that completely thats the only thing that i can thing of. Is there any way to take apart the stock rails to see if i have fuel in them. Ok what else can i do to test the rails? Thanks
 
#4
If you floor the gas pedal while and only while cranking, does it start when hot? You might have too much cranking fuel for a hot motor.
 
#6
If it does start when you floor it while cranking, look into the ECT. When you floor the pedal it shuts off the injectors. You may also notice a big bunch of black smoke too.

Good Luck
 
#8
Yes!! Possibally a faulty Engine Coolant Temp Sensor IF your car starts by pressing the pedal to the floor while cranking when your car is warm/hot

The ECT is along the black coolant tube between the passenger side valve cover and the upper intake towards the front

Have you checked for codes?
 
#9
Ok i will look for it but im kinda confused because I have a mechanical gauge? And no im still trying to find the right connector to wire in to get codes the previous owner is a jack*** and tried to clean up the wiring and cut that port off and then gave me a box with all the stuff he cut off lol As soon as i get the conn back on i will pull codes

Thanks for the help
 
#13
ok so I warmed up my car and shut it off At 160* and 190* and it started back up so then i let it run for awhile and it would not start again. It coughed for a second then nothing. I also floored the petal and nothing, it turned over great but nothing.

I let it cool down to 165* and it started, i let it go to 190* and shut it off and tried to start again and it would not start

I know that this is confusing but i tried to explain everything

And i looked for the wires to pull codes and couldnt find anything. It is on the drivers side by the firewall right?

Thanks for staying with me guys
 
#16
Yes i did check spark when it would not start.I did get a heat sink for my TFI and moved it to the drivers side firewall out of the heat and still nothing.

I have not done anything with the pip or stator, I figured that i still have spark when it will not start those parts are working correctly. Thanks for the help


Is it possible that my timing is off for some reason when i gets warmed up? Just trying to think of different things Thanks
 
#17
I recommend that you follow the links to the Wells site and read the tech notes there...

PIP problems & diagnostic info
Spark with the SPOUT out, but not with the SPOUT in suggests a PIP problem. The PIP signal level needs to be above 6.5 volts to trigger the computer, but only needs to be 5.75 volts to trigger the TFI module. Hence with a weak PIP signal, you could get spark but no injector pulse. You will need an oscilloscope or graphing DVM to measure the output voltage since it is not a straight DC voltage.

See http://www.wellsmfgcorp.com/pdf/counterp_v8_i2_2004.pdf and http://www.wellsmfgcorp.com/pdf/counterp_v8_i3_2004.pdf for verification of this little detail from Wells, a manufacturer of TFI modules and ignition system products.
 
#19
wow good article!! Well i wont be able to check voltage until i get off work but i did buy a new pip/ hall affect switch. I work for advance auto parts so i got a good one for just over $20. I will put it in and see if it changes anything. I will keep posting my progress


Thanks for the help
 
#20
Guess I should have posted the other part of the tech note... Sorry, but better late than never...

The PIP is a Hall Effect magnetic sensor that triggers the TFI and injectors. There is a shutter wheel alternately covers and uncovers a fixed magnet as it rotates. The change in the magnetic field triggers the sensor. A failing PIP sensor will often set code 14 in the computer. They are often heat sensitive, increasing the failure rate as the temperature increases.

The PIP sensor is mounted in the bottom of the distributor under the shutter wheel. In stock Ford distributors, you have to press the gear off the distributor shaft to get access to it to replace it.

To remove the gear, first you drive out the roll pin that secures the gear to the shaft. Then you get to press the gear off with a hydraulic press or puller. When you go to press the gear back on, it has to be perfectly lined up with the hole in the gear and shaft. I have been told that the hole for the pin is offset slightly from center and may require some extra examination to get it lined up correctly.

Most guys just end up replacing the distributor with a remanufactured unit for about $75 exchange
 
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