CUTTING FUEL

Sounds like your fuel pump is on it's last leg.

Use a fuel pressure test gauge available for rent/loan at most auto parts stores to check your fuel pressure when the engine acts up.

If the engine is cutting out and the fuel pressure is good, dump the codes and see what the computer says is wrong…Codes may be present in the computer even if the Check Engine light isn’t on.

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.



See http://www.troublecodes.net/Ford/
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is less than $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see http://www.midwayautosupply.com/p-7208-equus-digital-ford-code-reader-3145.aspx– It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $30.

JR's post is where I would also start.

Check fuel pressure before you start it and then note it again once it craps out. If pressure looks decent still, check for spark when it craps out. One or the other should be an issue, or you should see a big ol' code if it's something else.

Good luck.

BK_CAULEY said:

AND HOW DO I KNOW HOW MANY BLINKS MEAN WHAT NUMBERS. DO I COUNT A FLASH AS THE NUMBER THEN WAIT FOR THE PAUSE THEN THE NEXT SERIES OF FLASH'S AS THE NEXT NUMBER? LIKE THIS.. FLASH-FLASH..PAUSE..FLASH,FLASH,FLASH = 23?

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Yes, which method are you using to read codes. The codes should repeat for a second time and then a long pause for "hard" codes that may have been reocurring in the past. Do you have any codes??

BK_CAULEY said:

koeo eec-iv quick test and im not sure but i counted 3 times and according to the flash's im getting 95!! whats that?

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Should be a fuel pump power code as I recall. It comes up on MAF converted cars but in your case, it sounds like the FP is losing power perhaps. Jrichker will be along with a nice write-up about the code.

Good luck.

I have found in the past you may need to fix and clear all of the KOEO codes before moving on to the KOER test. Others may disagree but it has helped me in the past.
A couple of the codes you have described have all pointing to a spark problem. Checking TFI module would be a first suspect. EGR has a tendency to cause bucking and surging. Check the vac line to the EGR and it may need to be removed to check if the pintle vavle is not stuck. Just a few things to try.

Do you have a repair manual for your car, Haynes or Chiltons?? It is not easy to fix your car over the internet, but rather to point you in the general direction. Being this is your only car it may be wise to seek out some assistance from other mustang owners in your area. The TFI module is located on the front of the distributor with the wiring plug. The EGR valve is located in the inlet tract just after the throttle body facing the firewall. It is round in shape and has an electrical plug and vac line attached. It is also suggested that you attempt to fix the codes rather than just clearing them. If not, the codes will return and you right back where you started. Hope this helps.

To clear codes for a retest, disconnect the jumper while the codes are dumping or disconnect the battery for 10 minutes. Clearing the codes does not fix them, it just erases them so you can retest and see if they come back.

Code 12 -Idle Air Bypass motor not controlling idle properly (generally idle too low) - IAB dirty or not working. Take it off and clean it thoroughly with throttle body cleaner. Clean the electrical contacts with non flammable brake parts cleaner at the same time.

Code 14 - Ignition pickup (PIP) was erratic – the hall effect sensor in the distributor is failing. Bad sensor, bad wiring, dirty contacts. You have to press the distributor gear off the shaft to replace the sensor. The pip signal is used for ignition timing and fuel injector timing.

Code 18 - SPOUT out or wiring fault - look for short to ground in SPOUT wiring going back to the computer. Possible bad TFI.

Code 33 - Insufficient EGR flow detected.
Look for vacuum leaks, cracked vacuum lines, failed EGR vacuum regulator. Check to see if you have 10” of vacuum at the EGR vacuum connection coming from the intake manifold. Look for electrical signal at the vacuum regulator solenoid valves located on the rear of the passenger side wheel well. Using a test light across the electrical connector, it should flicker as the electrical signal flickers. Remember that the computer does not source any power, but provides the ground necessary to complete the circuit. That means one side of the circuit will always be hot, and the other side will go to ground or below 1 volt as the computer switches on that circuit.
Check for resistance between the brown/lt green wire on the EGR sensor and pin 27 on the computer: you should have less than 1 ohm.

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host)

http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif


EGR test procedure courtesy of cjones

to check the EGR valve:
bring the engine to normal temp.
connect a vacuum pump to the EGR Valve
apply 5in vacuum to the valve.
if engine stumbled or died then EGR Valve and passage(there is a passageway through the heads and intake) are good.
if engine did NOT stumble or die then either the EGR Valve is bad and/or the passage is blocked.
if engine stumbled, connect vacuum gauge to the hose coming off of the EGR Valve
snap throttle to 2500 RPM (remember snap the throttle don't hold it there).
did the vacuum gauge show about 5in vacuum?

if not, check for manifold vacuum at the EGR vacuum valve.
if you have manifold vacuum then connect vacuum gauge to the EGR valve side of the vacuum valve and snap throttle to 2500 RPM.
should read about 5in vacuum

The operation of the EGR vacuum regulator can be checked by using a test light applied across the wiring connector. Jumper the computer into self test mode and turn the key on but do not start the engine. You will hear all the actuators (including the EVR vacuum regulator) cycle. Watch for the light to flicker: that means the computer has signaled the EGR vacuum regulator successfully.


Code 95 - the following test path is for 86-90 model Mustangs.

The 95 code is because at one time or another, the fuel pump relay hiccupped and didn't provide power the pump when the computer told it to run. Sometimes this is a one time thing, other times it is a no run or runs poorly condition.

To help troubleshoot the 95 code, follow this link for a wiring diagram http://www.autozone.com/images/cds/gif/large/0900823d80167162.gif

Using the diagram, check the red/black wire from the fuel pump relay: you should see 12 volts or so. If not, check the inertia switch: on a hatch it is on the driver’s side by the taillight. Look for a black rubber plug that pops out: if you don't find it, then loosen up the plastic trim. Check for voltage on both sides of the switch. If there is voltage on both sides, then check the Pink/black wire on the fuel pump relay: it is the power feed to the fuel pump. No voltage there, check the Orange/Lt blue wire, it is the power feed to the fuel pump relay & has a fuse link in it. If there is good voltage there & at the Pink/black wire, swap the relay.

Some Mass Air conversions neglect to run the extra fuel pump wire, and they always have a 95 code. See http://www.stangnet.com/tech/maf/massairconversion.html for more information on the Mass Air wiring conversion.

The TFI module and pip faults are the top suspects for your problem. The TFI often fails when it gets hot and causes problems similar to yours. Remove the TFI module from the side of the distributor and have the auto parts store check it. Use a hair dryer to heat it since the problem only occurs when it is hot. Clean the TFI mount area good and use plenty of fresh heat sink compound on the TFI when you put it back on.

If the TFI checks out good, the pip is suspect. Seeing that you got a pip fault code, I would suspect it first. The pip is the sensor is in the bottom of the distributor that triggers the TFI. You have to press the gear off the distributor shaft to get access to it to replace it. Most guys just end up replacing the distributor with a reman unit for about $75 exchange.

The TFI is not a special part, any good auto parts store should have it. I have gotten TFI modules from Advance Auto Parts before.

Go back and re-read my post on how to test the TFI module. You may need to bring your own hair dryer to heat it up for testing.

Test the EGR position sensor prior to replacing it. Replacing the EGR valve is expensive and unnecessary.

Some basic theory to clarify how things work is in order…

The EGR shuts off at Wide Open Throttle (WOT), so it has minimal effect on performance. The addition of exhaust gas drops combustion temperature, increases gas mileage and reduces the tendency of the engine to ping. It can also reduce HC emissions by reducing fuel consumption. The primary result of EGR usage is a reduction in NOx emissions.

The EGR system has a vacuum source (line from the intake manifold) that goes to the EVR, computer operated electronic vacuum regulator. The EVR is located on the back of the passenger side shock strut tower. The computer uses RPM, Load. and some other factors to tell the EVR to pass vacuum to open the EGR valve. The EGR valve and the passages in the heads and intake manifold route exhaust gas to the EGR spacer (throttle body spacer). The EGR sensor tells the computer how far the EGR valve is open. Then computer adjusts the signal sent to the EVR to hold, increase or decrease the vacuum. The computer adds spark advance to compensate for the recirculated gases and the slower rate they burn at.

There should be no vacuum at the EGR valve when at idle. If there is, the EVR (electronic vacuum regulator) mounted on the backside of the passenger side wheelwell is suspect. Check the vacuum line plumbing to make sure the previous owner didn’t cross the vacuum lines.

Diagram courtesy of Tmoss & Stang&2birds. (the diagram says 88 GT, but the EGR part is the same for 86-93 Mustangs)


The EGR sensor is basically a variable resistor, like the volume control on a radio. One end is 5 volt VREF power from the computer (red/orange wire). One end is computer signal ground (black/white), and the middle wire (brown/lt green) is the signal output from the EGR sensor. It is designed to always have some small voltage output from it anytime the ignition switch is the Run position. That way the computer knows the sensor & the wiring is OK. No voltage on computer pin 27 (brown/lt green wire) and the computer thinks the sensor is bad or the wire is broken and sets code 31. The voltage output can range from approximately .6-.85 volt.


EGR test procedure courtesy of cjones

to check the EGR valve:
bring the engine to normal temp.
connect a vacuum pump to the EGR Valve
apply 5in vacuum to the valve.
if engine stumbled or died then EGR Valve and passage(there is a passageway through the heads and intake) are good.
if engine did NOT stumble or die then either the EGR Valve is bad and/or the passage is blocked.
if engine stumbled, connect vacuum gauge to the hose coming off of the EGR Valve
snap throttle to 2500 RPM (remember snap the throttle don't hold it there).
did the vacuum gauge show about 5in vacuum?

if not, check for manifold vacuum at the EGR vacuum valve.
if you have manifold vacuum then connect vacuum gauge to the EGR valve side of the vacuum valve and snap throttle to 2500 RPM.
should read about 5in vacuum

BK_CAULEY said:

the guys at advance auto parts here are total idiots. i asked them if they had a TFI module and they said no. then told me my car doesnt have one. i asked about the PIP module and i got that confused dog look. i went to oriellys and got a TFI but they dont carry a PIP. and i hope all these parts fix the problem. cause if they dont im gonna be screwed.

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Yeah…they have no idea what "TFI" means. Next time you can try "ignition module" instead and they should understand. The same goes with the PIP…aka "stator".