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help me get rid of engine codes...

  • Thread starter Thread starter 85cleangtvert
  • Start date Start date Nov 24, 2005
8

85cleangtvert

Member
May 19, 2005
103
1
18
Nov 24, 2005
#1
  • Nov 24, 2005
  • #1
I have a digital scanner. It works great. So far I have gotten rid of a few codes. But some are still left. The car im working on is my 88 5.0. I am still getting code 33, which says in the book is the EGR. But my EGR looks new. It was on the car when I bought it. Maybe u guys know what the common problem is when the code 33 comes up, as I dont... I am also getting code 29 for the VSS, but I am guessing that is because my speedo doesnt work. and I have a code 67, which says it is A/C clutch... how do I get rid of this ? I no longer have any of the A/C stuff hooked up in my car. It has a A/C delete kit and no condensor. I dont get a check engine light anymore after fixing my 02 sensors, but I would like to get the code 33 and 67 fixed if possible. as for the 29, I need to see why my speedo doesnt work. Im guessing the cable is broken. Besides the speedo not working, how much does having the code 29 effect the way my car runs? thanks for the help and happy thanksgiving!
 

HISSIN50

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Nov 24, 2005
#2
  • Nov 24, 2005
  • #2
Do a search for each code number. Jrichker has some WONDERFUL troubleshooting posts to help you get rid of each code.

If you had the car in gear during the tests, 67 pops up.

Good luck.
 

jrichker

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Nov 24, 2005
#3
  • Nov 24, 2005
  • #3
Code 29 - Vehicle Speed Sensor (VSS) is an electronic sender mounted on the speedo pickup gear on the trans. It works the cruse control for both 5 speed and auto trans cars. The VSS is used to tell the computer to speed up the idle as you slow to a stop. This helps keep the engine from stalling when you slow down for a stop sign or stop light.
Check to see if the electrical connector is plugged into it. Clean the connector & contacts with non flammable brake parts cleaner prior to replacing the sensor, as that may fix the problem. The sensor cost is under $30 and it is easy to replace.

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


Code 67 - clutch not depressed (5 speed) or car not in neutral or park (auto) or A/C in On position when codes where dumped. Possible neutral safety switch or wiring problem. This code may prevent you from running the Key On Engine On tests. You can generally ignore this code, since it has no effect on engine performance.
 
8

85cleangtvert

Member
May 19, 2005
103
1
18
Nov 24, 2005
#4
  • Nov 24, 2005
  • #4
thanks! my car does die sometimes after I get off the freeway... must be the VSS/ speedo connection... Im going to check out the EGR and all the lines to check for vac. leaks... and the code 67 is probably because my car was in gear when i did the test.
 
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