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Discussion Starter #1
So I took the car out yesterday to run some errands and enjoy it before winter comes. I start it up and the brake and low oil light is on. It does this from time to time and I never have been able to figure it out. Its not low on oil, and the brake light stays on after I take off the ebrake. Both lights eventually go off, but this is a mystery to me.

Another thing that happened yesterday is while at cruise I got a quick slight jerk. I did not pay much attention as once in a blue moon it does this. But about a mile from home still at cruise I had a HARD Jerk and CEL came on. I lost ALL Control of the accelerator pedal and the car just went down to idle like it was in neutral.
I pulled over on a side road near my house and had ZERO throttle control at all, but idled fine. I shut the car off and attempted to start back up and struggled. I gave it some pumps of the pedal while starting and cranked up and spit a huge puff of smoke out and smelt like fuel and went back to normal.

I checked for cels today and nothing indicative of this problem. Oil and brake light back on now too.

Not sure if my cluster is going bad and thats the explanation of the lights? Or maybe the other issue indicative of the TPS going bad maybe?

Any ideas? I am completely lost as to where to start on this and if any has any relevance to each other
 

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My guess is that (drum roll) you have electrical problems.

You say that you checked codes... what did you find?

(btw, make certain that your grounds are secure, along with the cable that connects the +12V terminal to the "power distribution block".
 

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Two things I would do.
1) Check and clean your MAF sensor
2) If your O2 sensors have a lot of miles on them I would replace them.
 

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Discussion Starter #4
Its not MAF or 02 sensors. . 02 sensors are shut off completely and tuned in open loop and the MAF is basically new. Id say less than 1k miles, so its not old enough to be dirty yet.
Alot of folk are telling me they experienced similar issues when their PIP or even the DIST in general is going bad. I find these strange anomolies for dist, but starting to make some sense with what I am reading. The entire ignition system is original from 94 and 155k miles.
I may try to get a NOS Ford dist to throw on this winter and see how it does unless any other suggestions. My initial thought was TPS, but I am not thinking so now.
 

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Discussion Starter #5
My guess is that (drum roll) you have electrical problems.

You say that you checked codes... what did you find?

(btw, make certain that your grounds are secure, along with the cable that connects the +12V terminal to the "power distribution block".
There are no codes I was not aware of. I get a code for having a chipped ECU and code for no EVAP Purge which are obviously planned. I did get one for the ECT, but that was from starting cold I am sure. That was just replaced within the last 2k miles, but that would not cause this anyway if it were valid.

Grounds were all checked prior. Car runs tip top otherwise, Just that happened and freaked me out. So unless a ground just broke off, I dont see that as being an issue. But I will check
 

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start at the brake light and low oil,

solve those instead of ignoring them, you will learn the powers of a dvom

then you can move onto the throttle control........

you have no 02s run in open loop,,,,,why?

If you want diagnose the dist, you can do minimal diagnosis with a dvom, power ground, and switched ground, the PIP.........

all ground and power checks should be done as a voltage drop test, NO OHMssss

common ground issues are the ones near the washer bottle and battery tray.
 

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Discussion Starter #7
start at the brake light and low oil,

solve those instead of ignoring them, you will learn the powers of a dvom

then you can move onto the throttle control........

you have no 02s run in open loop,,,,,why?

If you want diagnose the dist, you can do minimal diagnosis with a dvom, power ground, and switched ground, the PIP.........

all ground and power checks should be done as a voltage drop test, NO OHMssss

common ground issues are the ones near the washer bottle and battery tray.

Indy thank you for the response. On the O2 sensors. . ... Well I am not the tuner and it is not relevant to the issue, so I am not going to open that can of worms.
As far as the brake and low oil lights coming on when started ocasionally, I would not know where to start with that. I am pretty positive the sensors work otherwise as the brake light comes on with the ebrake cable fine. I set and reset and it does not go off when this happens. Both these lights go together each time it happens. Is there anything specific that could control these together? Or do you feel this could be ground related as you mentioned where to check grounds?

How would I diagnose the dist since it only happened that one time with loss of throttle control. The blip happened about 3-4x maybe over the last 4-5 months. The dist is original from 94 though as well as everything inside it. TFI could not cause anything like this could it?. I did have to relocate that for the blower. It is tucked on the frame rail now because where it was relocated to started rubbing a tad on my hood so I just unbolted it and tucked down lower and left it alone.
 

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the brake light has a power-load-ground and so does the oil light

looking at your wiring diagram, you want to id the circuit, find it, and check the power and ground.

I already told you what you can test with dist, you can also check spark output power with a spark test tool

actual testing of the signal from the dist, you need a scope
 

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Discussion Starter #9
problem is I think this stuff is going to be hard to diagnose if I cannot catch it when it does it. Spark test is only gonna tell me if I have spark at that point. Not gonna tell me if I am losing spark randomly once a blue moon at part throttle. I know I have spark 99% of the time atleast. That 1% is the issue though. Honestly I may just replace the dist as preventative maint at this point. Im sure its past its prime anyway.

Otherwise, I guess I will just try and find the schematics of the car and diagnose sometime over the winter while in storage as I get time. The lights dont bother me much if its just a glitch in the light. I know it has oil and pretty sure the brakes are not applied.
The more concerning part was the blip and loss of throttle it gave me the other day. That will cause me to sit on the side of the road and not so much the dummy lights going on for whatever invalid reason. I will check grounds again, although I did this back in the spring time when I thought this was ground related
 

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transistors,,,,,,can breakdown from heat and vibes......

you drive and LOG, the scope, to find the anomaly,,,

there is no glitch, or blip that goes away on its own......

diagnose it or don't......change parts if you like.....

and if you checked the grounds back in the spring...........HOW, visually?

what was the voltage drop on it?
 

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Discussion Starter #11
transistors,,,,,,can breakdown from heat and vibes......

you drive and LOG, the scope, to find the anomaly,,,

there is no glitch, or blip that goes away on its own......

diagnose it or don't......change parts if you like.....

and if you checked the grounds back in the spring...........HOW, visually?

what was the voltage drop on it?
I am not a shop and do not have a scope. I drive maybe 1k miles a year on this car, so even if I did have a scope it is kind of hard to diagnose and may drive for months with a very expensive diagnostic tool plugged in to catch it.

Yes I visually checked to make sure the grounds were attached , not frayed or broken off. Past that, no I have not done voltage drop tests.
I guess what I am asking here is please dumb down what you are asking me to do. I am not a shop or professional mechanic. If I had such equipment and skill level to diagnose such anomolies, i likely would not have asked others opinion.

That being said, I can either assume a certain 23yr old vital part to be bad from experience and other opinion, or I can test it. If you can advise how to test it without spending more money on the tool to test than the part costs, I am game to try it. If asking to do a specific test, please try to dumb down a little for me what you are asking to do. What am i testing voltage drop across? The specific sensor you think is the problem between its power pin and ground? Or just power from the battery to ground while the car is running? Ect?

I deff appreciate the help. You seem to be the only person to every answer anything on this forum, but please realize not everyone's experience is quite as vast as yours or have quite as detailed array of professional tools as you do. If I posted on the forum, its because I have no clue where to start. I am comfortable enough to figure out most things on my own, or use google until my eyes and fingers bleed before asking questions. Sometimes getting a few ideas from guys that have been through the ringer with these cars can help get on the right track before going too nuts with items that are not related. Some people have the tendancy to over diagnose and I really would like to keep that to a minimum.
 

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I gave you a couple ways to quickly check what is needed, with the tools you have

The scope is necessary for issues you have, I know the vast majority don't have that.

But guess what, there are plenty of shops out there that do, even mobile.

To get true answers I suggest you contact them, instead of looking for opinions.

My suggestions to you, are what you need to do, your job is find how to do it with what you have and supplement accordingly.

and there is no such thing as over diagnose, that is a BS.

'Assuming' is what is mostly over used.
 

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Discussion Starter #13
What i meant by over diagnose is on other boards guys telling me to check my ABS module, asking about my 02 sensors, ect. Stuff like that is pretty obvious its not related. Thats how you get on the replacing everything phase without reason.
When people suggest throwing parts, I have no issue asking what reasoning they feel that part is the issue before taking it seriously.

Anyway thanks for the info. i will do the best I can do with my knowledge and tools. If it gets beyond me, I will take to a dealer to see if they can diagnose if it gets that far. I have never let anything like that get past me, but there is a first for everything.
 

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ask here, show some initiative, get a wiring diagram, got questions on what and how to test'

ask...........

not only will you solve the problem, you will learn as well
 
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