Questionthanks for that idea... it might be a few days before we get to test the alternator, but that gives me a good idea about what may be going on... my dad raised a question about whether or not that line is looking for the minimum voltage coming from the alternator, or from the battery? and sorry about calling it juice... -------------------------
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new development... today i went to see my dad so that we could fix the brake line he damaged while putting the gas tank back onto the car... it ran perfectly all of the way to his house, which is a good 60 miles away... i paid close attention to anything odd, but found nothing out of the ordinary... once we fixed the brake line we took it for a test drive and the voltage guage, which had been hovering just above 13 volts, the midpoint, dropped drastically and was jumping up and down between 8 and 13 volts... it didn't matter what i turned on or off, it just kept freaking out... the car didn't stall still, but about ten miles later when the voltage guage started acting funny again the car did stall... i pulled to the side of the road and it cranked for a good minute bfore firing up again... i asked dad if it could be the voltage regulator in the alternator going bad, but he said that if the battery had enough juice left to crank that much until it started, then it should have had enough juice to keep the car running... i'll check, as you suggested, the plugs to see if they are firing properly, but wonder if this new information helps with a diagnosis? thanks-------------------------
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it stalls and restarts, but only with a little coaxing... normally it takes about a minute or two and it fires right back up...
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i recently got my 88 olds 98 from a friend of my dad's... they told him the car died after driving about 25 miles and then wouldn't start until it cooled down... dad decided it was the ICM and replaced it, along with the plugs and plug wires... we took it for a test drive and it made it 80 miles or so with no issues... we took it back and parked, but when i went to leave it stalled going down the road... it didn't take much to restart, but it's been stalling more often since then, and sometimes takes a minute or two to start... it will continue the pattern of stalling two or three times, sometimes more, and then go 100 miles or so before acting up again... dad decided it was the fuel pump, so we replaced the fuel pump and fuel filter... since then it has only stalled three times, but it's been only two days and it's obvious that we didn't fix the real problem... it runs like a dream except for those rare stalls, but it sometimes stalls on the highway and i have to make a quick exit to keep from being run down... since we changed the fuel pump it seems to stall only in town or when i am going more slowly... it's not died on the highway since those repairs, but i don't want to risk it... dad and i have been driving ourselves nuts trying to figure this one out... any help or suggestions would be greatly appreciated...
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at this point when it stalls will it restart or does the engine just turn over and the engine will NOT start ?.
Give me the latest problem.
autohelp
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What you need to check is that when it will not start, Check for spark to the sparl plugs as you crank the engine over.
Check for spark at ALL the spark plugs, NOT JUST AT ONE.
What we are trying to determine is if you have an IGNITION or a FUEL problem.
Check for spark at ALL the spark plugs and let me know.
autohelp
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OK, There is a voltage reference line that is monitored by the vehicles computer system and IF the voltage drops below 8 or 9 volts on this reference line to the computer the computer will SHUT OFF the engine in order to protect the electronic components within the computer and the other electronic components of the vehicle.
This is TRUE with ALL electronically controlled vehicles.
Since the voltage regulator is built within the alternator, I would recommend that you take the alternator OFF the vehicle and take it into any larger auto parts store such as AUTO ZONE or the like and they will test the alternator for FREE. Personally, Even IF the alternator checks out OK, I would replace it as what is most likely happening is that the BRUSH PACK within the alternator is worn out.
You CAN have the alternator rebuilt, But since it is an 88 year vehicle, I would not recommend it.
Please do NOT refer automotive electrical current as JUICE.
autohelp
AnswerApparently your father used to work on the old cars that were NOT computer controlled as did my father.
Trying to explain the differences in the older non-computerized vehicles and the computerized vehicles was always a NIGHTMARE between us.
Although true, On non-computerized vehicles, the engine would run until the battery was just about DEAD FLAT DECEASED.
NOT true with the new electronics as the diodes, chips, resistors and transistors that make up the vehicles electronics will NOT function on less than 8 to 9 volts.
On your particular vehicle the reference line is sensed by the computer via the alternator and when the alternator output voltage drops below the minimum voltage as stated above, the computer shuts down the ignition system of the vehicle otherwise the low voltage would start to destroy critical internal computer components.
It ONLY takes a second or two of low voltage for the computer to shut down the ignition system. So if there is an intermittent contact within the alternator such as worn brushes within the brush holder an you are getting an intermittent contact (ON and OFF) of the brushes on the alternator rotor this will cause a low voltage reading of which the computer senses instantly thus shutting down the ignition system.
IF the vehicle has had it's normal maintenance work done such as cleaning and checking battery connections, cables and testing the battery at recommended intervals as well as fan belt tightness as I do on a regular basis, My FIRST suspect would be to test the alternator.
However, Since maintenance seems to be a forgotten procedure, Nothing gets checked or tested anymore until something fails which usually happens on a friday night out in the middle of no where in the pouring rain.
If you do NOT perform the recommended maintenance procedures when they are due, Then I would suggest that you check the following Before having the alternator tested:
1. Is the fan belt tight on the alternator ?. If you can turn the alternator pulley by hand, The belt is NOT tight enough and or the belt is stretched and needs to be replaced.
2. Are the battery terminals clean and tight ?.
3. Is the POSITIVE battery cable tight at the starter post ?.
4. is the NEGATIVE battery post tightly secured to the engine block ?.
5. When was the last time you tested the battery ?.
6. When was the last time you tested the alternator ?.
&. Have you checked BOTH battery cables for corrosion and or discolorization under the plastic insulation ?.
ANY one of the above items can cause a low and or intermittent voltage signal, Thus shutting down the ignition system. Then once you start to crank the engine the vibration of the engine turning over makes a reconnection and this process is repeated over and over.
My dad and I used to get into some pretty good arguments mainly due to his knowledge of the non-computerized vehicles vs my 25 + years with working with computerized vehicles when they just started to come out back in the late 70's and early 80's.
If your dad is like mine, your going to have a LONG ROAD TO HOE in trying to teach him HOW and WHY the electronics on today's vehicles operate. Even showing my dad how the electronics works in BLACK and WHITE right out of the factory service manual he was still NOT convinced.
Unfortunately dad passed away several years ago, So now I have nobody to fight with anymore, So treasure your argruments with him.
I can picture your dad shaking his head saying "CAN'T BE", It makes NO SENSE. but you have to remember that he is basing his argument on his knowledge of non-computerized vehicles.
autohelp
