CEL CODES

[nospeed_!2]

Ok i wnet out and got a ford code reader from Walmart and plugged it in. and this is the code pattern i got

335
335
1
122
332
____

122
332

the "____" was a long pause


please help me interpret these~!~!~!

 

[MrShorty]

The first 335 is a KOEO hard fault code. It means that the computer didn't see the right electrical signal from the DPFE When the test was initiated. (Codes are repeated for each test, hence there are 2 335's)
1 is a separator pulse to separate the KOEO hard fault codes and the continuous memory codes.
122 and 332 are continuous memory codes. These are faults that the computer saw sometime during the last 80 or so "drive cycles"
122 indicates a fault in the TPS circuit.
332 indicates an EGR fault (sounds related to the hard fault code doesn't it.)

By the book, you would figure out the hard fault code first. Then perform the KOER test and diagnose any codes there. Then, clear the continuous memory codes and see if they come back.

For a complete EEC-IV diagnostic article, including circuit "pinpoint" tests for the codes, get a hold of a good manual like a factory emissions manual. Mitchell or Motor manuals are often found at libraries, someone posted a link to Mitchell's EEC-IV article for a '95 Explorer that has good information that would still apply to your '93 over in the Explorer forum at FTE (www.ford-trucks.com/forums). Do a search for "gtest.pdf", being sure to set the search option so it will search last summer's posts.

 

[nospeed_!2]

so what do you think is causing the problem oh and what is the "DPFE"?

 

[MrShorty]

I can't remember the acronym, but it's the sensor that tells the computer what the EGR is doing. It measures the pressure difference across the EGR valve. There are a few different variations on the theme depending on how the EGR system is engineered. Could be a bad sensor or it could be bad wiring between the sensor and the PCM. Here's what the gtest.pdf file has to say for a code 335 (for a '95 Explorer)

8) Code 335: Verify KOER Codes
Code 335 indicates DPFE sensor is out of self-test range (2.
6-4.2 volts) and may be faulty. DPFE system can detect lack of
pressure in exhaust system. A garage exhaust ventilation system,
installed during KOEO SELF-TEST, may cause DPFE sensor to generate
Code 335. Remove exhaust ventilation system. Repeat KOEO SELF-TEST.
Service codes as necessary. If no codes are present during KOEO SELFTEST,
complete QUICK TEST. If Code 335 is present during KOEO SELFTEST,
go to next step.
9) Check DPFE Sensor Pressure Input Hose
Remove pressure feed tube from DPFE sensor. Inspect tube,
including DPFE inlet, for blockage. Repair if necessary, and repeat
QUICK TEST. If no blockage is found, go to next step.
10) Measure VREF Circuit Voltage
With ignition off, disconnect DPFE sensor wiring harness
connector. Turn ignition on. Measure voltage between VREF and SIG RTN
terminals at DPFE sensor wiring harness connector. If voltage is 4-6
volts, replace DPFE sensor and repeat QUICK TEST. If reading is not 4-
6 volts, go to CIRCUIT TEST C.

 

[Albino 94LTD]

I saw an episode of 2 guys garage where they had an explorer on the rack. It had EGR codes and they said to remember to take off the throttle body and clean both sides very well. They showed the back side and it was all carbon'd up.

Here is the URL for that episode

http://www.twoguysgarage.com/episodes/episode.php?epi=210

I just got the light today and it is for 335 and 332.

I intend to replace the DPFE and associated hoses, the EGR valve and take the TB off and clean it too.

I suggest we all not overlook the backside of the TB!

 

[nospeed_!2]

let me know how that goes for yah and a rough cost. what were your symptoms on the Ex? stalling and stuff?

 

[Albino 94LTD]

No stalling or rough idle, just the check engine light with those codes.

My MPG hasn't beeen too good, so hopefully it will help.

so far it's $111 from Autozone internet (includes shipping) still need to get the hoses but that is only a buck or two.

I'll let you know the results