• Welcome Visitor! Please take a few seconds and Register for our forum. Even if you don't want to post, you can still 'Like' and react to posts.

codes 175 176 red and grey pcms are not alike there is life from the bog


smegun

Member
Joined
Jul 16, 2019
Messages
51
Reaction score
0
Points
6
Location
florida
Vehicle Year
1994
Make / Model
ford explorer
Transmission
Automatic
if im looking at skeematic(pdf) I notice an area( } ) were limited is noted if I follow traces I see the o2 sensors are in the circuit with the cmp .... I asked a patron about it ... I was asking cause I got continuity beeps from the red grey wire and lt blue grey wire across the harness and engine bay in areas so I was asking about a possible grounding issue while testing the wire harness for cross talk looking possibly for a faulty sensor ...the patron relieved me to state its a common ground to the sensors and its supposed to do that …. finer notes : there are a few areas on the schematic of which we were conferring on ...what is called "hot in run" and "limited only" my truck got codes 216 and 563 I solved the 216 it was a relay that was temper mental as well the truck ran that much better... I checked fuse 18 also but it was solid ...I still had the 563 error supposedly the inertial fuel switch but doesn't appear disconnected yet … still not there yet I drove the truck again tonight and came up with two new codes 175 176 o2 sensor codes …. I thought my pcm was ok ?...I like the way it goes through the test sequence I can here it working the switches I even thought there was a squeegee of the ABS unit ...sounds like a wet dream
:)
:) "something I had been looking forward too isolating an earlier ABS question of how to bleed the unit "

my last experiment this evening was a pcm change because I remembered I pulled the unit above from the yard an almost virgin explorer the one with a white monochrome grill I should of took the whole truck but that's another story someone already took the seats and carpets they must of been cherry it was right front totaled with 30k on it so I stole the brain on a half off day ….it had been In my truck since the day of experiments :/ ... I knew after short test run tonight it wasn't quite right yet and I had the two new codes so I put in the original pcm duh ! the truck is almost running as expected as from a complete head job its somewhat hopeful again just that much better ! ... ill pull the codes again soon but I think there is something to think about here on the circuit with the o2 sensors is that the firmware / changes in the pcms do different things … like the truck runs better now but the brakes are not as firm ? and the way it handles the o2's I want to believe that the circuit is actuated differently concerning the PCM like the cpm and o2 sensors on these lines and maybe the fueling regarding the 563 … still have much to do on truck but maybe it was never meant to get away from the build date on these PCM boxes check out attachments and tell me what you think constructively pleas supposedly this is an area of strict C of types like one pcm auto bleeds on the test sequence so weres that? that fuel pressure is maped differently ? that brakes are primed differently ? as there is more breaking power with the former PCM ?

the lable and main numbers look to be the same to the most part for the PCM's UMP1 etc ......but up close the build dates are different ... have been having difficulty with tuning up the Explorer since this rebuild started from a dead motor brain /valve it lives again thought it was the crank sensor at least it got me running again on all cylinders ..
 

Attachments



alwaysFlOoReD

Forum Staff Member
TRS Forum Moderator
TRS Banner 2012-2015
TRS 20th Anniversary
Joined
Apr 13, 2009
Messages
13,870
Reaction score
5,030
Points
113
Location
Calgary, Canada
Vehicle Year
'91, '80, '06
Make / Model
Ford, GMC,Dodge
Engine Size
4.0,4.0,5.7
Transmission
Manual
2WD / 4WD
4WD
AFAIK your 2 pcm are identical other than build date.

Contact adsmo8 or RonD for help with the rest.

If possible use punctuation and paragraphs to separate the different questions. It makes much easier to read and understand.
 

smegun

Member
Joined
Jul 16, 2019
Messages
51
Reaction score
0
Points
6
Location
florida
Vehicle Year
1994
Make / Model
ford explorer
Transmission
Automatic
really? truck is finding new life every start its been a difficult top end rebuild if I take the pill out I might notice some minor idle changes not consistent
 

RonD

Official TRS AI
TRS Technical Advisor
Joined
Jun 2, 2012
Messages
25,291
Reaction score
8,296
Points
113
Location
canada
Vehicle Year
1994
Make / Model
Ford
Transmission
Manual
Yes, I agree with alwaysfloored, PCMs are the same, any noticed running issue between them would be internal circuit issues, which can happen at 25 years old

No connection between PCM and power brakes but..........power brakes do use engine vacuum, so test vacuum at warm idle, expected is 18-21"
Codes 175/176 would also point to vacuum leak

Code 563 may be for AC WOT Relay, do you have one?
But in any case it won't effect engine operation
 

alwaysFlOoReD

Forum Staff Member
TRS Forum Moderator
TRS Banner 2012-2015
TRS 20th Anniversary
Joined
Apr 13, 2009
Messages
13,870
Reaction score
5,030
Points
113
Location
Calgary, Canada
Vehicle Year
'91, '80, '06
Make / Model
Ford, GMC,Dodge
Engine Size
4.0,4.0,5.7
Transmission
Manual
2WD / 4WD
4WD
really? truck is finding new life every start its been a difficult top end rebuild if I take the pill out I might notice some minor idle changes not consistent
AFAIK the pcm takes a few drive cycles to learn the sensor variables. It may take a bit to settle down.
Were the pcm pulled from vehicles with same type trans? Tho the pcm numbers should be slightly different if different types.
Edit: RonD confirmed pcm.
 

smegun

Member
Joined
Jul 16, 2019
Messages
51
Reaction score
0
Points
6
Location
florida
Vehicle Year
1994
Make / Model
ford explorer
Transmission
Automatic
got 4 new relays to put in tonight ....when I pull the pill and there is some idling fluctuations im wondering how good my injectors are I tested them all roughly the same impedance and made a rig to blow some carb cleaner through them but mabe there tired
 

alwaysFlOoReD

Forum Staff Member
TRS Forum Moderator
TRS Banner 2012-2015
TRS 20th Anniversary
Joined
Apr 13, 2009
Messages
13,870
Reaction score
5,030
Points
113
Location
Calgary, Canada
Vehicle Year
'91, '80, '06
Make / Model
Ford, GMC,Dodge
Engine Size
4.0,4.0,5.7
Transmission
Manual
2WD / 4WD
4WD
What is a "pill"? Or is that spell check....
 

smegun

Member
Joined
Jul 16, 2019
Messages
51
Reaction score
0
Points
6
Location
florida
Vehicle Year
1994
Make / Model
ford explorer
Transmission
Automatic
like the octane bar its in the front by the battery used to run a timing check I believe
 

RonD

Official TRS AI
TRS Technical Advisor
Joined
Jun 2, 2012
Messages
25,291
Reaction score
8,296
Points
113
Location
canada
Vehicle Year
1994
Make / Model
Ford
Transmission
Manual
You are running a 4.0l OHV with an EDIS-6 spark module, not sure why you would be messing with the octane shorting bar(aka SPOUT), the EDIS-6 is one of the better spark modules, unless vehicle was in a front end collision, because its usually located on the front or back of rad support, so gets damaged.
If EDIS-6 was "hit" then replace it, lots of OK used ones around

Removing the jumper from Octane bar(SPOUT) disconnects "Vacuum advance" data from PCM to EDIS-6
The EDIS-6 can do RPM spark advance but can't to "vacuum advance" only the PCM can do/calculate that info, but for instant throttle response you need "vacuum advance" not just RPM advance
 

smegun

Member
Joined
Jul 16, 2019
Messages
51
Reaction score
0
Points
6
Location
florida
Vehicle Year
1994
Make / Model
ford explorer
Transmission
Automatic
very interesting ......I was referring to the pill in the front by the edis module yes

...did a fresh boot of the pcm and test drive had one flash of the engine light for a minute during travels then did the paper clip got a 172 koer and a 176 koeo im lean I guess not to confident with injectors or a fuel line but here were talking vaccume and wondering were I might have a prob ? ... newer booster master newer headjob manifold gaskets feel more breaks than before headwork not seeing it a vacume leak yet ?? ….. maf o2 sensors dirty long sleep ? not quite up to power seems a little rough little vibratory a little slow acceleration vac advance interesting anything I can do to play with the vac
 

smegun

Member
Joined
Jul 16, 2019
Messages
51
Reaction score
0
Points
6
Location
florida
Vehicle Year
1994
Make / Model
ford explorer
Transmission
Automatic
ive run the kritter with the octane bar out for a short spell before I had headwork done some years ago thought it had more torq at the time and also had good results with it in on a long trip like mysterious miles extra ????
 

smegun

Member
Joined
Jul 16, 2019
Messages
51
Reaction score
0
Points
6
Location
florida
Vehicle Year
1994
Make / Model
ford explorer
Transmission
Automatic
Yes, I agree with alwaysfloored, PCMs are the same, any noticed running issue between them would be internal circuit issues, which can happen at 25 years old

No connection between PCM and power brakes but..........power brakes do use engine vacuum, so test vacuum at warm idle, expected is 18-21"
Codes 175/176 would also point to vacuum leak

Code 563 may be for AC WOT Relay, do you have one?
But in any case it won't effect engine operation

had purge valve reversed direction evidently for short time did a little clean out with some foam I was getting some fumes and noticed some improvement I had already cleaned out the lower intake but the throttle body has one port connected to the purge valve I may have relieved some tension ….my next question is does the transmission ever wind up with a baffle of vaccume to the system ? I mean it advances the switch of gears but is it possible that there is a problem any link would be nice
 

smegun

Member
Joined
Jul 16, 2019
Messages
51
Reaction score
0
Points
6
Location
florida
Vehicle Year
1994
Make / Model
ford explorer
Transmission
Automatic
what can i do to improve the vacuum advance ? ? was on a stretch of highway its a slow speed gainer like no passing I mean it gets there 60 miles an hour but slowely no traffic performance yet ... the heads sound ok together but its just boggy like not enough mix to do the trix …. I want to change my fuel lines and I put in newer aftermarket injectors roughly 2O# bosch copy yellow tops 710's they found the other cyl that was tacky still maybe not enough fuel mix to burn could of had a non egr brain would that of helped?? ….. I wont call it a truck till it does what it did when it did what it does ...I could be hearing some late detinations sounds like a little lifter clatter late not tic but similar at times ...
 

Attachments

smegun

Member
Joined
Jul 16, 2019
Messages
51
Reaction score
0
Points
6
Location
florida
Vehicle Year
1994
Make / Model
ford explorer
Transmission
Automatic
Yes, I agree with alwaysfloored, PCMs are the same, any noticed running issue between them would be internal circuit issues, which can happen at 25 years old

No connection between PCM and power brakes but..........power brakes do use engine vacuum, so test vacuum at warm idle, expected is 18-21"
Codes 175/176 would also point to vacuum leak

Code 563 may be for AC WOT Relay, do you have one?
But in any case it won't effect engine operation
538
 

RonD

Official TRS AI
TRS Technical Advisor
Joined
Jun 2, 2012
Messages
25,291
Reaction score
8,296
Points
113
Location
canada
Vehicle Year
1994
Make / Model
Ford
Transmission
Manual
Code 538 means you were in Test mode and didn't push down gas pedal when you should have, the "goose test"
So not about a running issue
 

Sponsored Ad


Sponsored Ad

Staff online

Member & Vendor Upgrades

For a small yearly donation, you can support this forum and receive a 'Supporting Member' banner, or become a 'Supporting Vendor' and promote your products here. Click the banner to find out how.

Truck of The Month


Kirby N.
March Truck of The Month

Recently Featured

Want to see your truck here? Share your photos and details in the forum.

Follow TRS On Instagram

TRS Events

25th Anniversary Sponsors

Check Out The TRS Store


Sponsored Ad


Sponsored Ad

Sponsored Ad


Amazon Deals

Top