Codes how do I fix?

[86bluecobra]

Ok while driving my speed density 302 ocasionally the check engine light comes on. After you continue to drive it goes out. So the light came on and this time i was able to go home and do a Key on Engine Off scan. It came up with these codes:
172 HEGO sensor fault/lean
173 HEGO sensor fault/rich
327 EVP/EPT circuit below minimum voltage
332 Insufficient EGR flow detected

Now a little info on the engine. (this is a 92 f-150) It is a 92 302 with factory heads and factory truck intake. It has comp cams computer controlled cam in it. A little info on the cam is intake duration 258 exhaust duration 264, valve lift .481 on both intake and exhaust, lobe seperation is 114 degrees. It has a set of shortie headers, a off road bassinni y-pipe and a flow master dual exhaust (kinda a chevy dual with one 3 inch in dual 2.5 inch out).
Something i do notice when i have pulled the intake off is that there seems to be excessive amount of what apears to be oil in it. it will leak out the TB if you tip it.

 

[86bluecobra]

man not even jrichker could help me?

 

[86bluecobra]

Ok i don't know exactly what this means but i pulled the vaccuum line off the egr. My miss went away. Yes the check engine light now comes on and stay's on but i guess that is to be expected since now the egr can not open. Anyone know what this means? Do i need to buy a new EGR or just evp sensor?

 

[billison]

how much is the egr? if it's cheap i'd change it anyway just to be safe

 

[jtfairlane]

Ok while driving my speed density 302 ocasionally the check engine light comes on. After you continue to drive it goes out. So the light came on and this time i was able to go home and do a Key on Engine Off scan. It came up with these codes:
172 HEGO sensor fault/lean
173 HEGO sensor fault/rich
327 EVP/EPT circuit below minimum voltage
332 Insufficient EGR flow detected

Now a little info on the engine. (this is a 92 f-150) It is a 92 302 with factory heads and factory truck intake. It has comp cams computer controlled cam in it. A little info on the cam is intake duration 258 exhaust duration 264, valve lift .481 on both intake and exhaust, lobe seperation is 114 degrees. It has a set of shortie headers, a off road bassinni y-pipe and a flow master dual exhaust (kinda a chevy dual with one 3 inch in dual 2.5 inch out).
Something i do notice when i have pulled the intake off is that there seems to be excessive amount of what apears to be oil in it. it will leak out the TB if you tip it.

The HEGO errors are obviously your Oxygen sensors. Now I am not familiar with the exhaust setup on an eary nineties F series truck, but if you have an off-road Y pipe, and the oxygen sensors are downstream of the headers, is it safe for me to assume that it's possible that you're not running oxygen sensors anymore? Might they not have been swapped/replaced in the Y-pipe swap? Or, did you reuse high-mileage stock oxygen sensors? For the 5.0 mustang, it's recommended that O2 sensors be replaced every 50,000 miles. I would definitely figure out what your O2 sensor situation is.

Causes of getting an insufficient EGR flow code can be the EGR valve itself, the EGR sensor, a bad EGR vacuum line, etc. I got a similar code on my 5.0 Mustang a while back. The vacuum lines were all good, so I removed the EGR sensor and valve. The valve had a bunch of carbon buildup in it so I cleaned it as best I could. Reinstalled, ran the test again, same error code. I had another EGR sensor (known to be good) handy and swapped sensors, ran test, same code. I finally broke down, bought a new EGR valve, ran the test, and the code went away. I hope this helps.

 

[Glaze]

no they arent cheap....and a true mechanic diagnosis before replacing. i know id feel better purchasing a part that i knew was defective.

richker has a post somewhere lost in the forums that explains how to check the EGR with vaccum pump. And i would also check the egr sensor also as it might be throwing off valve.

 

[jrichker]

The following code information is for a 5.0 Mustang. It may or may not be accurate for an F150 truck with a 5.0 engine.

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.

 

[86bluecobra]

the o2 sensor was replaced with a brand new one when i did the y-pipe swap. 1 year ago. maybe 7500km's on the truck since then. i don't know if you glance over it jrichker but when i take the vaccuum line off my egr my trucks miss goes away. it is completely gone now. I think the miss is gone because of the lack of oil being sucked through the egr. When i had my intake off i notice oil leaking out off the TB. the seems to be bringing oil in. Which kinda seems wierd because i thought all it was supposed to be doing was bringing exhaust gases while the engine was warm to improve immissions and gas milage.

 

[HISSIN50]

but when i take the vaccuum line off my egr my trucks miss goes away.

I'm with the other guys. If removing the vac line to the EGR helps, I'd make sure there isnt any vacuum present in that vac line to the EGR at idle (when that vac line should be dead).

It would make sense that there's vacuum in it, since removing the line helps (the vac is pulling the valve open a little bit). This can be an EGR solenoid type issue, which can then screw with the EGR position sensor (it ruins the baseline calibration for a closed EGR valve).

Good luck.

 

[86bluecobra]

nope but i will do it next time i have a few days off. LOL my wife will kill me if she see's me tearing her truck apart again. she says something always goes wrong when i touch it and she is probably right.

 

[HISSIN50]

I edited my last post. I think I initially missed the boat. The edit makes more sense to me. And it's a super quick thing to check.

Good luck.