it's not running right, diagnose?
Thread Starter
Pro
Joined: Feb 2005
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From: Harrisburg, PA 86 Vert w/ 89 wheels
it's not running right, diagnose?
pretend i'm your granma (cause i'm not very good at diagnosing my car problems)
what i did: drove through some big puddles in my 86
why i'm concerned: (two things)
when i push on the gas pedal to move forward after a stop, the car will 'pause', feel like it's bogging down or something, then surge forward quickly.
doesn't happen consistently, but it's been occurring to some degree more often than not since the rain.
and
when i'm moving, (like when i'm trying to maintain 55 on the highway) the car will feel like I'd let off the gas pedal for a second even though my foot didn't move, and then it'll quickly go back to normal running
It FEELS like (in my foot, felt through the peddle)
vvvvvvvvvvvvvvvvvvvvvvvvvvvvdvvvvvvvvvvd vvdvvvvvvvvvvvvvvvv
(note the 'd's)
Now if i were trying to impress a girl by diagnosing my own problem i'd tell her my engine was misfiring, but since i've never actually been near a car that was misfiring while in the presence of a knowledgeable person who could listen and say to me 'it's misfiring' I would say there's a pretty fair chance that I'm just talking out my butt.
Anyways, anyone willing to give me some ideas?
what i did: drove through some big puddles in my 86
why i'm concerned: (two things)
when i push on the gas pedal to move forward after a stop, the car will 'pause', feel like it's bogging down or something, then surge forward quickly.
doesn't happen consistently, but it's been occurring to some degree more often than not since the rain.
and
when i'm moving, (like when i'm trying to maintain 55 on the highway) the car will feel like I'd let off the gas pedal for a second even though my foot didn't move, and then it'll quickly go back to normal running
It FEELS like (in my foot, felt through the peddle)
vvvvvvvvvvvvvvvvvvvvvvvvvvvvdvvvvvvvvvvd vvdvvvvvvvvvvvvvvvv
(note the 'd's)
Now if i were trying to impress a girl by diagnosing my own problem i'd tell her my engine was misfiring, but since i've never actually been near a car that was misfiring while in the presence of a knowledgeable person who could listen and say to me 'it's misfiring' I would say there's a pretty fair chance that I'm just talking out my butt.
Anyways, anyone willing to give me some ideas?
Le Mans Master
Joined: Feb 2006
Posts: 8,753
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From: Louisiana
Sorry, but from what you have stated...it could be tons of things causing the problems. How long since a basic tune up (spark plugs, wires, fuel filter, pcv valve, ect)?
Clean the throttle body and the IAC with throttle body cleaner and a small brush or Q-tips. Have you checked the gas for water?
Clean the throttle body and the IAC with throttle body cleaner and a small brush or Q-tips. Have you checked the gas for water?
Thread Starter
Pro
Joined: Feb 2005
Posts: 632
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From: Harrisburg, PA 86 Vert w/ 89 wheels
i did plugs and wires last year, and a competent shop removed and reinstalled them to do the cylinder heads during the winter.
fuel filter was done two years ago.
i cleaned out the throttle-body as well as i knew how to about two years ago as well.
pcv valve? i dunno what that is.
also wanted to say that water in the gas is something that i definately think i need to look into.
fuel filter was done two years ago.
i cleaned out the throttle-body as well as i knew how to about two years ago as well.
pcv valve? i dunno what that is.
also wanted to say that water in the gas is something that i definately think i need to look into.
Last edited by illinest; Aug 13, 2007 at 04:27 PM.
Thread Starter
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Joined: Feb 2005
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From: Harrisburg, PA 86 Vert w/ 89 wheels
i'd hope that the water would be dry by now, (2 or 3 days after the last rain)
no codes that stick. i usually get a check engine light during my ride but it's never there when i use my trusty paper clip.
it did come in earlier than usual once, (after the rain) but if i complained about something EVERY time my car acted up I'd be in here non-stop.
Last edited by illinest; Aug 13, 2007 at 04:50 PM.
Safety Car
Joined: Jul 2004
Posts: 3,845
Likes: 30
i'd hope that the water would be dry by now, (2 or 3 days after the last rain)
no codes that stick. i usually get a check engine light during my ride but it's never there when i use my trusty paper clip.
it did come in earlier than usual once, but if i complained about something EVERY time my car acted up I'd be in here non-stop.
no codes that stick. i usually get a check engine light during my ride but it's never there when i use my trusty paper clip.
it did come in earlier than usual once, but if i complained about something EVERY time my car acted up I'd be in here non-stop.
..ok, no codes..however, should water have found it's way into the maf, it'll take out the "heated sensor wire" inside..that would throw a code.....if you keep clearing the codes with a paper clip, you are solving nothing. pull the codes as it will be stored in the system and find out what it is....
Thread Starter
Pro
Joined: Feb 2005
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From: Harrisburg, PA 86 Vert w/ 89 wheels
..ok, no codes..however, should water have found it's way into the maf, it'll take out the "heated sensor wire" inside..that would throw a code.....if you keep clearing the codes with a paper clip, you are solving nothing. pull the codes as it will be stored in the system and find out what it is....
but this code that always comes in for me is never there after i turn the engine off and try to read it.
Safety Car
Joined: Jul 2004
Posts: 3,845
Likes: 30
of course it is not there when you turn the car off! the ignition has to be on and the paper clip "in use" to pull the codes.ok, let me ask it this way;
1)....when was the last time you car threw a code?...
2)....how often is the code thrown?
3)....what was it?...
4)....what did you do about fixing the cause of the code?
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Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
The PCV valve is located on the driverside valve cover. Pull it out and shake it...it should rattle. Also with the engine running, feel the PCV valve with your finger....you should feel a strong vacuum there.
I'm sure you know how to pull codes? Ground A and B on the ALDL and turn the key on. The SES light will blink a code 12 three time. If no codes are stored, the code 12 will be there everytime.
I'm sure you know how to pull codes? Ground A and B on the ALDL and turn the key on. The SES light will blink a code 12 three time. If no codes are stored, the code 12 will be there everytime.
Thread Starter
Pro
Joined: Feb 2005
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From: Harrisburg, PA 86 Vert w/ 89 wheels
The PCV valve is located on the driverside valve cover. Pull it out and shake it...it should rattle. Also with the engine running, feel the PCV valve with your finger....you should feel a strong vacuum there.
I'm sure you know how to pull codes? Ground A and B on the ALDL and turn the key on. The SES light will blink a code 12 three time. If no codes are stored, the code 12 will be there everytime.
I'm sure you know how to pull codes? Ground A and B on the ALDL and turn the key on. The SES light will blink a code 12 three time. If no codes are stored, the code 12 will be there everytime.
thanks for the pcv lead.
Thread Starter
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From: Harrisburg, PA 86 Vert w/ 89 wheels
updates. informational.
two new things.
let my foot off the pedal while i was going 40 on level ground.
1/2 mile later, down to 37 mph.
wtf?
then when i put the car in park to turn it off the engine went to 12 rpm instead of 6, and slowly revved higher until it hit 15 or so and i turned the key.
thing number 3. (the bonus thing)
I cycled the heck out of the throttle body at lunch today, and on the way home the car was reasonably well behaved again.
throttle body problem?
two new things.
let my foot off the pedal while i was going 40 on level ground.
1/2 mile later, down to 37 mph.
wtf?
then when i put the car in park to turn it off the engine went to 12 rpm instead of 6, and slowly revved higher until it hit 15 or so and i turned the key.
thing number 3. (the bonus thing)
I cycled the heck out of the throttle body at lunch today, and on the way home the car was reasonably well behaved again.
throttle body problem?