SN95 Intermittent Stalling. Will Restart Without Spout.

[fl4]

Let me start by saying I greatly appreciate any time you guys will save me. Divorce, blah blah, money and time.

Car
1995 Cobra
Stock engine. Stock computer. Mods are fuel pressure regulator, exhaust, gear, brakes, and suspension.

Problem
Car intermittently stalls. It will restart after it sits for a while. It will also restart immediately when the spout is removed.

Attempted solutions
• Removed motocraft TFI I installed a few years ago and installed another Motocraft TFI. Same problem.

• Pip sensor. Installed a Napa dizzy. Set timing to 10. Same problem.

• Fuel Pressure

Runs at 32 psi
When i shut it off, it immediately drops some, then raises and holds at 34psi.
After it sits warm, and I put the key in run (not starting), the puel pump whines. I get out and check, and its at 34psi.
Starting while hot, it goes to 32 psi.
​

• Took the computer out. it looks great. I dont see any burned out connectors. Connectors look good.

Unattempted solutions
I did not replace the computer. A few internet searches showed TMoss saying "Anytime a car runs with the Spout plug out but not in - it's the computer!"
Some more searches backed this up - This thread shows the same

Because the car will start and run with the spout out when the intermittent stalling occurs, do I assume
• The TFI is fine
• The PIP is fine
• I need to investigate the computer and wiring when the intermittent problem occurs?

If so, do I use this checklist?

1. Check for PIP signal at ECM connector, engine cranking (pin 56).... it should oscillate between 3 - 6 vdc.
2. If 1. fails, need to check for an open from pin 56 to the TFI connector, or short to power or ground.
3. Check for the same voltage output as in 1. at the SPOUT connector, engine running plug removed.
4. If 3. fails, check SPOUT wire from pin 36 at the ECM connector to the SPOUT connector and the TFI connector plug connected (same check as #2).
5. if 1-4 are a PASS..... ECM is kaput.​

Thanks for any help.

Edit; Just found this checklist. http://www.stangnet.com/mustang-forums/threads/mustang-cuts-out-and-dies-after-warm-up.827901/

 

[old_blue]

I was going to say look for jrichker checklist but looks like you already found it in that thread. Good luck and welcome to the boards.

 

[fl4]

I was going to say look for jrichker checklist but looks like you already found it in that thread. Good luck and welcome to the boards.

Thanks.

I can eliminate some of this, right? I'm interested in this, so I can cut out excessive parts purchasing. Like its running on the TFI when the spout is out, so we can deduce thats working.

 

[90lxwhite]

Thanks.

I can eliminate some of this, right? I'm interested in this, so I can cut out excessive parts purchasing. Like its running on the TFI when the spout is out, so we can deduce thats working.

Have you scanned for codes?

 

[fl4]

I have. No codes.

 

[tamadrummer88]

Member since 2007 and these are your first posts?

Strong lurking is strong

Btw welcome to the boards

 

[fl4]

Member since 2007 and these are your first posts?

Strong lurking is strong

Btw welcome to the boards

Thanks. I don't post unless necessary. This problem has me stumped, and I need my ride working.

 

[toyman]

I have. No codes.

Not even a 111?

 

[fl4]

Not even a 111?

Alright. You got me there. I do get the all good code. As in, I do get the 111.

 

[jrichker]

The link you posted to the Cranks OK but no Start checklist points to an out of date version. The current version says Revised 12-Dec-2011 to replace 10 pin salt & pepper connector graphic.
See http://www.stangnet.com/mustang-for...t-for-fuel-injected-mustangs-fox-sn95-5-0l.7/ for the current version.

PIP problems & diagnostic info
I highly recommend that you follow the link at the bottom of this post and read both articles.

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.

 

[90lxwhite]

Member since 2007 and these are your first posts?

Strong lurking is strong

Btw welcome to the boards

A lil creepy you know how long he's been a member.

 

[fl4]

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.

Thanks for the writeup, the link to the new version, and the reply.

Here is my question. What do I do considering that I replaced my distributor and I'm having the exact same problem? I mean, no change. I guess it can be possible that I have a problem andI replace a part that is broken in the same way. But, I'm wondering about the next most likely thing, so I'm not throwing the same parts at the car. What would be the next likely thing here? Relay? Ground? I can't really test a PIP. Its cheaper for me to buy another few PIP sensors than it is to buy a oscilloscope or graphing DVM.

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.

Thanks for the writeups. This is clearly the product of a lot of work.

 

[89stang1]

I would have put my money on pip/hall effects sensor cause i had exact symptoms and thats what fixed it but i see you changed it

 

[fl4]

I would have put my money on pip/hall effects sensor cause i had exact symptoms and thats what fixed it but i see you changed it

This problem has me frustrated.

 

[89stang1]

This problem has me frustrated.

I hear ya brotha ive had ignition problems put me on a flatbed more than once!, my car was doing same thing. One time i was on highway and it was like i turned key off but after 4 to 5 hours car would restart like nothing was wrong. good luck man

 

[jrichker]

If the distributor has any warranty left on it, swap it out. You wouldn't be the first guy to get a DOA part right out of the box.

 

[fl4]

If the distributor has any warranty left on it, swap it out. You wouldn't be the first guy to get a DOA part right out of the box.

Ill do it this week. Likely tomorrow.

I can deduce that that TFI works, right?

Also, considering the above, whats the next part I should throw at it?

Thanks.
(I really need to get this thing working. Your time is appreciated)

 

[toyman]

What we know for certain is you need air, fuel and spark so the problem will be one of these or a combination. Fuel pressure is on the low side so that may be suspect. It should be closer to 40 psi KOEO. Have you checked for fuel in the vacuum line at the FPR? Do you know for certain that the fuel pressure hasn't dropped below 32 psi? For air issues have you cleaned/replaced/tested the MAF, AIT and TP sensor(s)? As noted by others reman distributors are know to have bad PIPs.

 

[fl4]

What we know for certain is you need air, fuel and spark so the problem will be one of these or a combination. Fuel pressure is on the low side so that may be suspect. It should be closer to 40 psi KOEO. Have you checked for fuel in the vacuum line at the FPR? Do you know for certain that the fuel pressure hasn't dropped below 32 psi? For air issues have you cleaned/replaced/tested the MAF, AIT and TP sensor(s)? As noted by others reman distributors are know to have bad PIPs.

This AFPR isn't doing anything on my car. I dialed it back to stock a long time ago and never took it off as it wasnt a problem. Interesting about KOEO and it being a little low on pressure. Thanks for pointing it out.

A couple of years ago, I replaced the IAC, TPS, etc with motorcraft parts dealing with a surging idle. It ended up being the dizzy, and I installed a new old stock motorcraft distributor, which, unfortunately do not exist anymore.

 

[Micheal Nadeau]

A lil creepy you know how long he's been a member.

You have been a member for 3 years...........