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Topic: Curious?? (Read 3625 times) previous topic - next topic

Curious??

My 86 Cougar has me stumped. It has the 3.8L V6 and CFI. Okay, it runs choppy emits black charcoal like exhaust, (you can always tell where I park.) lacks power while accelerating, at times dies and sounds like it's timing is off. I have had the timing adjusted profesionally I gave up, replaced the plugs, wires, rotor, cap, the CFI, the ISCM, tried premium gasoline, and redid all of of it again, oh fuel filter-replaced. So out of nowhere she starts running perfect this lasted for two days, then  she just died. It was the alternator. what has me trippin out is how well it ran on just the battery, does anyone have information or know anything about this? Oh yeah I replaced the alternator and again it runs like %(*& well you know what I mean. Please help.

Re: Curious??

Reply #1 –
Sounds like your fuel mixture is way rich or you are burning oil.
The EEC computer controls the fuel mixture based on input it gets from some sensors. Mainly exhaust gas oxygen, throttle position and engine temperature sensors.

Have you tried to pull error codes from the EEC?
What did those plugs look like? badly gunked up?
Was the timing off when you had it checked?

Re: Curious??

Reply #2 –
Thanks for replying, way cool. My plugs have a very small amount of carbon buildup when pulled, My timing was and is correct and I dont know how to pull the codes? Would you be able to tell me or direct me to a source that would?  :grinno:

Re: Curious??

Reply #4 –
STOP!!!
 Don't try the proceedure in the previous post. The connectors they show are correct but I think there are problems with the way they want you to jumper them.
I think grounding both the STI and STO may damage something.

Your car my not have a check engine light.

Someone on this board has nice pictures of the hook up for using an buttstuffog volt meter or a test light to read out the codes. Hopefuly they will post it for you here shortly.

Re: Curious??

Reply #6 –
Since you suspect electrical problems you should get an inexpensive buttstuffog multimeter. Thats the kind with a needle that swings across the dial.
You can check your battery voltage. It should around 12.5 volts with the car not running and 14 to 14.5 volts with the car running and the alternator charging. If the voltage goes way high with the car running, the voltage regulator is bad.

You can use this same meter to "read out" the computer codes.

Don't know if you have any experience with volt meters. I hav'nt bought one in many years but I think most car parts places have them and hardware stores.

If you need help using it I can help.

Re: Curious??

Reply #7 –
Check your map sensor.....

Last time it happen to me my Map sensor Was barely unplugged and i was runing rich...


Black smoke = Carbon = Lack of Oxygen....

Re: Curious??

Reply #8 –
either that, or there is the possibility of your fuel pressure regulator being shot, if there is a hole in the diaphram, it will give full pressure to the injectors, causing a rich condition
It's Gumby's fault.

Re: Curious??

Reply #9 –
Don't know if it applies to Fords, but a friend's 280Z was running off-&-on rich, & it turned out his temperature sensor connector was loose, causing the computer to think it was at absolute zero, thus the full rich condition.  Some yahoo "Z-car specialist" lost the spring-lock & replaced it with a chunk of paper clip, which allowed the intermittent connection.

Re: Curious??

Reply #10 –
Here is a good link showing how to pull EEC-IV codes. It seems a little more straight forward than the previous link posted. Unless you have some electrical gremlins, running on battery alone won't change how the car runs. The reference voltage for the EEC-IV is 5 volts. So until the system's voltage drops below 5 volts, the sensors don't care. There is also a voltage compensator function in the computer which will account for variations in voltage while running. As said before, pull/post the codes and let the body of knowledge here go to work.

Re: Curious??

Reply #11 –
if you happen to live near an auto-zone parts store you can get the codes read for free. is all you do is ask the guys behind the counter to run them for you. i'm not shure but i think i remember pep boys doing tis also? :slap:
I love it when a plan comes together!!!-Hanibal Smith (A-Team)

Re: Curious??

Reply #12 –
sounds like a cat to me. I had mine plug up on me. I couldn't figure out what was wrong. I had all the same symtoms. I replaced all my sensors to figure that out.  I can almost positive thats your problem.

Re: Curious??

Reply #13 –
Thank you all for your thoughts and ideas and help. I am a bit overwhelmed with everything i have learned and am still learning yet I am studying and reading and just checkin it out. I have another question, Where is my map sensor? Oh yeah I checked out my Brain eveything is connected and snug, could it be my ignition module on my distributor? I just keep reverting back to how it ran perfect without my alt.  :evilgrin:

Re: Curious??

Reply #14 –
the map sensor for my 88 5.0 is on the firewall, behind the upper intake manifold. it has an electrical connection as well as a vacuum hose that's going to the intake manifold. my car was running like total shiznit too, it wouldn't idle for anything, but ran fine if I was at WOT.turns out the hose going to the map sensor had somehow come off/rotted. I put it back on and it would still run like shiznit sometimes, turns out the tube bends right as it gets to the sensor, and was rotted and broken there, so if it was pushed a little it would open up, thus telling the map sensor there was no vacuum and that I was at WOT. what i don't get is that it totally disregarded the TPS signals...