[Cougar5.O]

While "throwing parts" at it is wasteful and hoping on luck, I'm eager to see if Indy is willing to fly to where this person lives and show them how to do these basic tests.

 

[TheZ06andFoxbody]

While "throwing parts" at it is wasteful and hoping on luck, I'm eager to see how if Indy is willing to fly to where this person lives and show them how to do these basic tests.

I’m fully a beginner and I have a lot to learn. I also don’t want to screw something up by fiddling with the wrong stuff.

At the same time, I’m getting conflicting advice from local shops and my mechanic, and what I’m seeing on here. So I’m doing the best I can under the circumstances.

 

[indy2000]

Ok, what do you suggest?

see if the sensor is lying, for the ecm to trigger a DTC, it must have met the rich limit

therefore, check sensor signal at the ecm, then at the sensor connector

you could have an open signal wire, ie melted to exhuast...........

get dirty, start testing, or take it in.........

 

[Enjoy_the_Ride]

in theory, if it's the HEGO, resetting the eec should allow it to idle for a while before hitting the fueling limit. If it starts right away after a battery reset, could be wiring.

 

[indy2000]

yes you can erase KAM and therefore long term fuel trims

 

[90MarkVII]

You have the EGR not opening correctly code.
IF the EGR valve has stuck in the open-or partially open-position, it will idle very poorly to not at all if the EGR valve is allowing EGR gasses into the intake at idle. It is supposed to happen only at part throttle (cruising).
This would also cause a lean condition as unmetered air (gasses) are entering post MAF.

If you have a vacuum hand pump, attach it to the EGR valve, pull vacuum on it and see if the valve moves in and out.
Even if it does, though, it could have carboned up to the point it will not close properly.
Consider picking up an EGR valve gasket, pull the valve and take a look at it.

 

[TheZ06andFoxbody]

You have the EGR not opening correctly code.
IF the EGR valve has stuck in the open-or partially open-position, it will idle very poorly to not at all if the EGR valve is allowing EGR gasses into the intake at idle. It is supposed to happen only at part throttle (cruising).
This would also cause a lean condition as unmetered air (gasses) are entering post MAF.

If you have a vacuum hand pump, attach it to the EGR valve, pull vacuum on it and see if the valve moves in and out.
Even if it does, though, it could have carboned up to the point it will not close properly.
Consider picking up an EGR valve gasket, pull the valve and take a look at it.

I don’t have an EGR on the car anymore, so I’m not sure if it’s related to that system

 

[90MarkVII]

I don’t have an EGR on the car anymore, so I’m not sure if it’s related to that system

Well, scratch that idea.....

 

[TheZ06andFoxbody]

I’ve talked to a few local shops and some of my buddies in the car community down here and I really don’t understand how it could be anything but the O2 sensors. All the TPS/IAC stuff on the car is brand new and the car ran just fine for over a year and I haven’t adjusted or changed anything before this problem developed. The car does not have any issues other than at idle. It does not ping or belch smoke or anything. All the vacuum lines and **** are intact. All the electrical stuff appears to be intact. The computer was reworked with new capacitors relatively recently. Salt and pepper shakers were redone recently. New fuel pump, etc. The car does not have an EGR or a smog system. There are no melted wires or faulty connections or any of that.

I feel like I can run tests until I’m blue in the face but what is the actual theory as to what’s wrong here at this point? Does anyone have any actual thoughts on what the issue might be? What am I even looking for as far as a test result and what would that point to??

I’m a beginner and people say “test this test that” and I’ve done everything I can up to my skill level but people are saying oh check the electrical signals for this and that and I straight up don’t know how to do that ****.

Example:

“therefore, check sensor signal at the ecm, then at the sensor connector”

I don’t know how to do this. I don’t know where this **** is and I don’t know even know what the **** I’m looking for.

I’m gonna be sticking electrical probes in random connectors in the far without a clue. None of these tutorials online show exactly what to do. It’s just “make sure the voltage is XYZ” and I have not a ****ing clue how to do that.

Dont underestimate how new I am to this. Yes, I have to be told exactly what to use to perform the electrical test and exactly where to stick the wires. Don’t assume I know any of that **** because I dont!! If the goal here is to teach me how to do stuff on my own, it’s certainly going to fail if I have zero way of figuring out how to perform these tests and I just end up taking the car to a shop. I don’t have any experience at all so the mantra of “you should know how to do this or figure it out” doesn’t really help. I didn’t have the benefit of having a figure in my life teaching this **** to me growing up and anything I’ve searched countless hours for online is just conclusory. I don’t even know what people are referring to half the time and what good does it do to try to diagnose this **** if I’m doing it wrong in the first place??

I honestly don’t think anyone has any idea what the actual problem is. I’m trying to get the car to a shop but everyone is booked up for weeks and I’m starting to feel like I’m chasing my tail here.

 

[Blown85GT]

Well, you can try to reset KAM.

Disconnect battery for ~30 minutes, reconnect and start it up and see what happens.
If it continues to run after it warms up, seems like you can look into the O2 issue.

 

[TheZ06andFoxbody]

Well, you can try to reset KAM.

Disconnect battery for ~30 minutes, reconnect and start it up and see what happens.
If it continues to run after it warms up, seems like you can look into the O2 issue.

Hmmm I did try this. Disconnected the battery, turned the headlight switch on (to drain residual charges/current from the system, idk someone said todo that) and waited an hour and then reconnected the battery. No changes from doing that, it still shuts off same as it did before.

 

[indy2000]

I’ve talked to a few local shops and some of my buddies in the car community down here and I really don’t understand how it could be anything but the O2 sensors. All the TPS/IAC stuff on the car is brand new and the car ran just fine for over a year and I haven’t adjusted or changed anything before this problem developed. The car does not have any issues other than at idle. It does not ping or belch smoke or anything. All the vacuum lines and **** are intact. All the electrical stuff appears to be intact. The computer was reworked with new capacitors relatively recently. Salt and pepper shakers were redone recently. New fuel pump, etc. The car does not have an EGR or a smog system. There are no melted wires or faulty connections or any of that.

I feel like I can run tests until I’m blue in the face but what is the actual theory as to what’s wrong here at this point? Does anyone have any actual thoughts on what the issue might be? What am I even looking for as far as a test result and what would that point to??

I’m a beginner and people say “test this test that” and I’ve done everything I can up to my skill level but people are saying oh check the electrical signals for this and that and I straight up don’t know how to do that ****.

Example:

“therefore, check sensor signal at the ecm, then at the sensor connector”

I don’t know how to do this. I don’t know where this ** is and I don’t know even know what the ** I’m looking for.

I’m gonna be sticking electrical probes in random connectors in the far without a clue. None of these tutorials online show exactly what to do. It’s just “make sure the voltage is XYZ” and I have not a ****ing clue how to do that.

Dont underestimate how new I am to this. Yes, I have to be told exactly what to use to perform the electrical test and exactly where to stick the wires. Don’t assume I know any of that **** because I dont

I honestly don’t think anyone has any idea what the actual problem is. I’m trying to get the car to a shop but everyone is booked up for weeks and I’m starting to feel like I’m chasing my tail here.

people that already know system design and theory of operation, are telling you what to test for

no one is beside you to tell you what to connect and how, THAT IS UP TO YOU TO DO

YOU NEED WIRING DIAGRAMS IN FRONT OF YOU, YOU WANT TO LEARN, BUY THEM

NOBODY CAN DO THIS WITHOUT THEM

sounds like you want to fix your car, with this ‘simple’ fix from the internet


PEOPLE MAKE A LIVING. fixing cars like yours, you are the one that decided you want to fix, without any prior knowledge, how did you think it was going to turn out?

AND STOP WITH THE, ‘I DONT UNDERSTAND IT WAS RUNNING FINE ONE MINUTE THEN THE NEXT NOT’

all things work UNTIL THEY DONT

so shall we stop with diagnosis?

sounds like you are a quitter

 

[TheZ06andFoxbody]

people that already know system design and theory of operation, are telling you what to test for

no one is beside you to tell you what to connect and how, THAT IS UP TO YOU TO DO

YOU NEED WIRING DIAGRAMS IN FRONT OF YOU, YOU WANT TO LEARN, BUY THEM

NOBODY CAN DO THIS WITHOUT THEM

sounds like you want to fix your car, with this ‘simple’ fix from the internet


PEOPLE MAKE A LIVING. fixing cars like yours, you are the one that decided you want to fix, without any prior knowledge, how did you think it was going to turn out?

AND STOP WITH THE, ‘I DONT UNDERSTAND IT WAS RUNNING FINE ONE MINUTE THEN THE NEXT NOT’

all things work UNTIL THEY DONT

so shall we stop with diagnosis?

sounds like you are a quitter

"PEOPLE MAKE A LIVING. fixing cars like yours, you are the one that decided you want to fix, without any prior knowledge, how did you think it was going to turn out?"

And there we have it, folks. Of course it's not going to turn out well. I guess my mistake was trying to fix it myself and asking people on the internet for advice.

Quite frankly, I don't even know how to read a wiring diagram and interpret that based on what's on the car. I've looked up schematics from past threads on forums and I don't know where to start. Every piece of literature on this topic is geared toward someone who already has a basic understanding of these systems.

I do have the wiring diagrams.

Mustang FAQ - Wiring & Engine Info

http://www.veryuseful.com/mustang/tech/engine/images/o2SensorTests.gif

What does it mean to connect the DMM sensor between the EGO signal wire and the negative battery terminal? Between? Like where exactly? That seems like a lot of wiring, am I supposed to just pierce the wire insulation with the voltmeter somewhere between the battery terminal and the signal wire? What is the difference between an EGO and a HEGO as it pertains to this test? Do you see why I'm asking for help on how to do this? If I could read wiring diagrams and perform these tests, do you really think I'd be here asking for help?

Picture me as someone who doesn't know the first thing about any of this. You really think I'm going to be able to just look at this and perform those tests correctly? No, I'm going to be taking shots in the dark. That's why I'm asking for input - I want to perform these tests correctly so I'm not wasting my time and everyone else's time.

Aren't you the one who was giving me **** about performing superfluous tests? Like how you said no one asked me to unplug the IAC with the engine warm? When I performed that test, I did it in a way that made sense based on what I had read online and in the Haynes manual. And you came on here giving me **** for doing it incorrectly. So now I'm asking for clarification on how to do the tests and you're telling me to just figure it out? Not sure what the thought process is here.

"No one is beside you to tell you what to connect and how, THAT IS UP TO YOU TO DO"

So I'm supposed to just know this **** huh? Just like magic? I'm not asking you to fly down here and do the tests for me, dude.

This is starting to seem a lot more like gatekeeping than helping diagnose the issue.

So, in sum, we have no real theories about what is causing the issue. If I'm understanding the earlier posts correctly, haven't we ruled out the 02 sensors by the fact that I unplugged the battery and cleared the computer, and it's still having the problem exactly the same as before? Something about long term fuel trims?

I spoke to one of the techs at Steeda (they're local to me). He said it's almost definitely not the O2 sensor. He thinks it's an issue with the distributor or spark. Which doesn't make much sense either, since I've had two TFIs and one distributor go bad, and these symptoms I'm having now aren't even close to what I experienced with those failed parts.

 

[indy2000]

you need wiring diagrams, that tell you where the connectors are, and pin numbers, wire colors etc

they cost money, the wiring diagram you post are generic termination diagrams

rarely are the wiring home runs like in those diagrams

you can ask all the questions you like, I certainly dont have a problem with that

I have a problem when you dont put the effort in to learn, USE YOUR TIME NOT mine.

go to the 02 sensor and follow the wiring to the connectors back to the ecm

I will explain what and how you need to test it

want to learn, or not?

dont feel bad if you, this aint for a lot of people, that is why you can HIRE them

 

[Enjoy_the_Ride]

the very first thing I would do is crawl under the car and make sure both hegos are getting a good 12 volts. Then I would check the ground on the back of the engine (#19). Then check the Salt and Pepper connectors (#14 and #15).

 

[bradbrenn]

Make sure you don’t have any broken or severed wires and make sure all wires are tight in the plastic connectors. Every time I’ve disconnected a harness plug in the past 5 years some of the wires literally fall out the plastic connectors. I’ve had to remedy this the best I can and make it a habit to thoroughly clean every single pin, every time I unplug a harness connector. I’ve pretty much covered them all by now and mine starts and runs like new. It has taken a long time, years really and my car has been down weeks and even months at a time.
Patience is key if you are going to be your cars technician, which can be hard when you just want to enjoy the car. It can be maddening!
Seems like your trying to devour all this very quickly almost like taking a mini session college course which has its obvious pros and cons.
Sometimes a sabbatical can help as well. There have been times I’ve brought it to the shop, other times I have grinded it out, other times taken extended breaks and played more golf haha.
I’ve learned you are pretty much forced to learn if you want to own one of these cars cause they are just simply getting old.

Hang in there man!

 

[TheZ06andFoxbody]

you need wiring diagrams, that tell you where the connectors are, and pin numbers, wire colors etc

they cost money, the wiring diagram you post are generic termination diagrams

rarely are the wiring home runs like in those diagrams

you can ask all the questions you like, I certainly dont have a problem with that

I have a problem when you dont put the effort in to learn, USE YOUR TIME NOT mine.

go to the 02 sensor and follow the wiring to the connectors back to the ecm

I will explain what and how you need to test it

want to learn, or not?

dont feel bad if you, this aint for a lot of people, that is why you can HIRE them

Alright I'm going to order some. Did not know something like that existed.

Of course I want to learn. I’m eager to learn as much as I can as quickly as possible. I'm in a position where I got into this side of the hobby a little later in life and am basically starting from scratch. I've always been a huge car guy but I didn't have anyone to teach me this stuff growing up. My parents disallowed it and for 10 years after I focused on schooling and my career and didn't have enough money to get into the hobby side of things. I bought my 1991 about a year ago as a second car to enjoy it obviously, but also with the expectation that I'd learn to fix stuff on it myself and that it would be sort of an ongoing project to keep it running. But I'm finding a lot in the car community that there's a lot of gatekeeping with this. Like "oh you shouldn't be near a car if you don't know how to do this." Well, everyone has to start somewhere.

Don't underestimate how much of a beginner I am at this. I want to eventually be able to handle stuff like this and much more complicated stuff on my own, but I think people sometimes take for granted that I don't know how to do basic stuff. So much of the literature online and elsewhere is geared toward someone who already has a basic working command of how to do stuff.

 

[vinnyc5566]

Damn he is wasting a lot of peoples time on 2 separate sites. I think at this point you just need to cough up the $120 and get a real diagnostic from a shop lol it would be better than throwing away money on parts and crossing your fingers.

 

[Cougar5.O]

Shop will charge $120 and give a wrong diagnosis 50% of the time though. I've complained also, but let the person learn. Personally, I'd have turned the idle screw enough to allow it to idle and then diagnose from there, but I am a person that loses my mind when an engine won't stay running!

 

[TheZ06andFoxbody]

Damn he is wasting a lot of peoples time on 2 separate sites. I think at this point you just need to cough up the $120 and get a real diagnostic from a shop lol it would be better than throwing away money on parts and crossing your fingers. View attachment 1075224

Oh wow you got me, I posted on a different forum to try to get as much advice as possible. Lmao asking questions is wasting people's time? Feel free to move on if you have nothing to add, boss man. Sounds like you don't have any theories on what it is either.