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Idle Problems.. new thread for problems

  • Thread starter Thread starter savegoodautonfg
  • Start date Start date Jul 31, 2007
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patrickmx2

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Sep 17, 2007
#81
  • Sep 17, 2007
  • #81
savegoodautonfg said:
I just took a look under my hood. I have one thick cable going from the battery it looks as if it dips under the car and goes to maybe the starter?

Then i have another one small one that goes from battery to the chassis and another wire comes out of the same connection to the chassis which goes to some connector it looks like.

I can't see the block grounds nor do i know where the holes to put them into are?
Click to expand...

YES. That in BOLD above is this:




The "SOME CONNECTOR" you mention should be THIS below

 

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jrichker

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#82
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The computer pin 46 signal ground is a critical component: it provides ground for the TPS, ECT, EGR position sensor and ACT. Signal ground is used in many circuits that have analog inputs to isolate the electrical noise. It is always separate from power ground, although both may have a common connection origination point. Signal ground usually has some conditioning that reduces the electrical noise to prevent false readings
The black/white wire (pin 46) is signal ground for the computer. It provides a dedicated ground for the EGR, Baro, ACT, ECT, & TPS sensors as well as the ground to put the computer into self test mode. If this ground is bad, none of the sensors mentioned will work properly. That will severely affect the car's performance. You will have hard starting, low power and drivability problems. What sometimes happens is that the test connector black/white wire gets jumpered to power which either burns up the wiring or burns the trace off the pc board inside the computer. That trace connects pins 46 to pins 40 & 60. Only an experienced electronics technician can open the computer up & repair the trace if it burns up and creates an open circuit.

If the ground for the TPS goes bad, the TPS output voltage increases and the idle speed goes up.



Troubleshooting signal ground problems:
Note that all resistance tests must be done with power off. Measuring resistance with a circuit powered on will give false readings and possibly damage the meter.
1.) With the power off, measure the resistance between the computer test ground
(black/white wire) on the self test connector and battery ground. You should see less than
2.0 ohms.



2.) MAP circuit: Check the resistance between the black/white wire on the MAP/BARO sensor and then the black/white wire on the EGR and the same wire on the TPS. It should be less than 1 ohms. Higher resistance than 1 ohms indicates a problem with the 10 pin connector or the splice inside the main harness where the wire from the 10 pin connectors joins the rest of the black/white wire. Next check the resistance between the black/white wire and the negative battery cable. It should be less than 2.0 ohms.

3.) Engine mounted sensor circuit: Check the resistance between the black/white wire on the TPS and battery ground. It should be less than 2.0 ohms. Higher resistance than 2.0 ohms indicates a problem with the 10 pin connector or the splice inside the main harness where the wire from the 10 pin connectors joins the rest of the black/white wire.

 

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savegoodautonfg

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#83
  • Sep 18, 2007
  • #83
Well Jritcher, i already changed the fuel injector harness and as far as i know the ground was fine for a month or so didnt stick at all. just started again.

jrithcer, do you think i should just try to run the new grounds like patrick said?
 
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patrickmx2

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#84
  • Sep 18, 2007
  • #84
The fuel injector harness plugs into the "salt and pepper" shakers. So where in that replacement did you even touch the ground mentioned above?

Unless you replaced the ENTIRE EEC harness you didn't touch the ground.
 
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savegoodautonfg

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#85
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The SIG-RTN wire??
 
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patrickmx2

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#86
  • Sep 18, 2007
  • #86
Yes. The ground you might be thinking about on the rear of the intake is the HEGO ground.

Go to www.fordfuelinjection.com and see if that helps you out any.

And don't take this the wrong way because my intent is not to insult. If you are having this much trouble trying to grasp the concept of just taking two bolts and securing a simple $5.00 24" inch wire to the car you should really ask a friend to help you with this. The reason I say this is because after all the pictures, arrows and such you mentioned replacing a starter wire after calling it a ground.

Again, I'm only looking out for you. Don't be insulted if I'm coming across wrong. I have some brilliant friends who are good at what they do for a living but know nothing about cars. At the same time I can't do their jobs as good as they can.

Patrick.
 
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savegoodautonfg

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NO INSULT TAKEN. thank you patrick
 
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savegoodautonfg

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#88
  • Sep 27, 2007
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Update:

I got into a situation last weekend and now because of it i'm broke. i have like 50 dollars to my name till i get paid next week.

Now i didnt do the ground yet, im going to try to do it today. but it was sticking and i let it keep sticking and i got into my driveway and popped the hood, i disconnect IAC connector and it went down to normal and then reconnected it and it went back up to 2,000 sticking again, then i disconnect TPS connector and idle went back to normal then hooked back up the TPS and it went to 2,000 sticking again.

What does this mean if anything?
 

jrichker

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The TPS is sending the computer bad data. That means either the TPS is defective, or the signal ground I have been writing about is bad.
 
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savegoodautonfg

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I've tried so many TPS already including a BRAND NEW one. It must be the signal ground. if that is it how is that fixed?
 

jrichker

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Read my post #82 in this series of posts. It is 9 posts back up the page.
 
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savegoodautonfg

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I ran a ground 4ga wire from the power steering bracket thing to the chassis and i have had any sticking from throttle body in 4 days????
 

jrichker

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Power ground for the alternator and signal ground for the TPS (black/white wire connected to pin 46 on the computer) are not the same thing.
 
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savegoodautonfg

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Well its strange because since i did that i havent had sticking in almost a week
 
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savegoodautonfg

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jrichker said:
1.) With the power off, measure the resistance between the computer test ground
(black/white wire) on the self test connector and battery ground. You should see less than 2.0 ohms.

With the car off, and my meter on 200 on OHM's I got a .6 OHMS



2.) MAP circuit: Check the resistance between the black/white wire on the MAP/BARO sensor and then the black/white wire on the EGR and the same wire on the TPS. It should be less than 1 ohms. Higher resistance than 1 ohms indicates a problem with the 10 pin connector or the splice inside the main harness where the wire from the 10 pin connectors joins the rest of the black/white wire. Next check the resistance between the black/white wire and the negative battery cable. It should be less than 2.0 ohms.

Black/White on Map and Black/White on EGR- .6 Ohms
Black/White on Map and Black/White on TPS- .6 Ohms
Black/White on EGR and Black White on TPS- .2 Ohms


3.) Engine mounted sensor circuit: Check the resistance between the black/white wire on the TPS and battery ground. It should be less than 2.0 ohms. Higher resistance than 2.0 ohms indicates a problem with the 10 pin connector or the splice inside the main harness where the wire from the 10 pin connectors joins the rest of the black/white wire.

I got no resistance with Black/White wire on TPS and Battery Ground..

But i did get resistance on the TPS Red/White wire and Battery Ground- .4 OHMS



Let me know guys...
Click to expand...
 

fastford91

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Aug 15, 2006
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Oct 5, 2007
#96
  • Oct 5, 2007
  • #96
ecu repair said:
hey whats up all,

im a ford lincoln mercury tech, i rebuild there ecu's. i have an microelectronics degree. i'm offering all the ford people with there mustangs cheep repair and testing. 50.00 flat rate for test & repair
(if repair is made).
if it tests good it will only be 25.00

shipping both ways is your call. ground second or next day delivery.
Click to expand...

THIS SOUNDS LIKE SPAMING TO ME!!! ILL HELP YOU FIX IT BUT IT'LL COST YA! THIS SIGHT IS ABOUT HELPING ONE ANOTHER WITH AS LITTLE OR NO COST AT ALL! WE DONT TRY TO MAKE MONEY OFF OF EACHOTHER PAL! THE REASON IM WRITING THIS IS BECAUSE I HAVE SEEN HIS POSTS IN ACOUPLE OTHER PLACES TONIGHT AND GUYS LIKE THIS PISS ME OFF!!! SOMONE BAN HIS ASS!!!
 

jrichker

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#97
  • Oct 5, 2007
  • #97
savegoodautonfg said:
jrichker said:
1.) With the power off, measure the resistance between the computer test ground
(black/white wire) on the self test connector and battery ground. You should see less than 2.0 ohms.

With the car off, and my meter on 200 on OHM's I got a .6 OHMS



2.) MAP circuit: Check the resistance between the black/white wire on the MAP/BARO sensor and then the black/white wire on the EGR and the same wire on the TPS. It should be less than 1 ohms. Higher resistance than 1 ohms indicates a problem with the 10 pin connector or the splice inside the main harness where the wire from the 10 pin connectors joins the rest of the black/white wire. Next check the resistance between the black/white wire and the negative battery cable. It should be less than 2.0 ohms.

Black/White on Map and Black/White on EGR- .6 Ohms
Black/White on Map and Black/White on TPS- .6 Ohms
Black/White on EGR and Black White on TPS- .2 Ohms


3.) Engine mounted sensor circuit: Check the resistance between the black/white wire on the TPS and battery ground. It should be less than 2.0 ohms. Higher resistance than 2.0 ohms indicates a problem with the 10 pin connector or the splice inside the main harness where the wire from the 10 pin connectors joins the rest of the black/white wire.

I got no resistance with Black/White wire on TPS and Battery Ground..

But i did get resistance on the TPS Red/White wire and Battery Ground- .4 OHMS



Let me know guys...
Click to expand...

The wire inside the harness where the TPS/MAP/Baro black/white wires join the black/white wire for the self test connector has a bad connection.

You get to split the harness open at the point where the 10 pin connector wiring joins the main harness and look for the splice in the black/white wire. When you find it, look for signs of the wire breaking under the insulation or a faulty crimp or solder joint.
Click to expand...
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
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108
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Oct 5, 2007
#98
  • Oct 5, 2007
  • #98
fastford91 said:
THIS SOUNDS LIKE SPAMING TO ME!!! ILL HELP YOU FIX IT BUT IT'LL COST YA! THIS SIGHT IS ABOUT HELPING ONE ANOTHER WITH AS LITTLE OR NO COST AT ALL! WE DONT TRY TO MAKE MONEY OFF OF EACHOTHER PAL! THE REASON IM WRITING THIS IS BECAUSE I HAVE SEEN HIS POSTS IN ACOUPLE OTHER PLACES TONIGHT AND GUYS LIKE THIS PISS ME OFF!!! SOMONE BAN HIS ASS!!!
Click to expand...

You're right, and I did. You're welcome

Please tone down the language though...
 
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savegoodautonfg

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#99
  • Oct 5, 2007
  • #99
You happen to have a picture?
 
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savegoodautonfg

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#100
  • Oct 5, 2007
  • #100
jrichker said:
savegoodautonfg said:
The wire inside the harness where the TPS/MAP/Baro black/white wires join the black/white wire for the self test connector has a bad connection.

You get to split the harness open at the point where the 10 pin connector wiring joins the main harness and look for the splice in the black/white wire. When you find it, look for signs of the wire breaking under the insulation or a faulty crimp or solder joint.
Click to expand...

Can i just get a replacement harness?
Click to expand...
 
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