somethin wrong with my 5s, rpm jumps and drops Options

[mikew04]

while driving my car in any gear or nuetral, or any throttle position, my engine will sporadically jump and die. the tack will flick up 1 or 2k rmp from what its at, then flick down to zero, and go back and forth really fast. this is happening for about five seconds or so at a time, and every few minutes. it occurs less often when the car is warmed up. the tach seems like its reading the rpms right, the car will jolt back and forth when this is happening, and the car wants to die on me as the tach reaches zero. when the tach goes down the check engine light flashes on, like it does if you stall. i checked for codes, and its not throwing any. i have a spark on all cylinders, and my spark plugs were replaced and gapped correctly. i checked the power connections and the grounds and everything looks fine. this is making it really hard to drive the car, especially in this weather. thanks for any help.
-mike

[Vibe]

Alternator? Just a guess....

[mikew04]

it does seem like an electrical problem, but i dont know... it does it whether i have as much as i can off, or lights, fan, and 2 amps going... bleh

EDIT: i did some more searches, and i think i found a few more people who had the same problem... some suggestions were air bypass valve, maf, and other sensors, but no one had a clear solution that worked.

This post has been edited by mikew04: Jan 30, 2005 - 4:19 AM

[Newbie]

Try unplugging the IAC vacuum line.. See if it idles steady..

[Junior]

throttle control valve

[mikew04]

It idles fine, its when im driving it that i have problems. its like its just missing really bad. also, im having trouble starting it. it kind of starts when it wants to. im thinking it could be a bad connection in the ignition switch, bc i put a starter kill in it when i did my alarm, but that was over the summer and its been fine till now. thats the next thing im going to check when i get a chance, but that might be a while... i hate not having a car at school i dont know when im going to see her next

[Digndoug]

My old dodge did this, with both the tach an speedo.. Never figured out the problem, ended up trashing it, but when i took it to two dif local shops, they said it could be a lot of dif things right down to bad coroded ground which would be a pain to find. At least for the dodge I had they said it wasnt worth the money for them to try an fix it.

[mikew04]

yah, im afraid of not being able to figure out what it is... i checked all the grounds, and most of them i redid a while back, so i dont think its that.
Digndoug - was the engine missing on you as well, or was it just the needles jumping up and down?

This post has been edited by mikew04: Jan 31, 2005 - 11:32 AM

[Digndoug]

yah, im afraid of not being able to figure out what it is... i checked all the grounds, and most of them i redid a while back, so i dont think its that.
Digndoug - was the engine missing on you as well, or was it just the needles jumping up and down?
[right][snapback]240437[/snapback][/right]

It was a lot of things,It was a dodge. But it was staling, misssing chugin, it was a pos. I finally got it running, by changing fuel injectore air filter gas filter, oil, plugs wires, cap, vacum tubes, radiator, thermosdat and a few odd cut wires. After all that i got it running pretty well, it still wasnt perfect, and once in awhile the speedo would cut out, but i still never figured that out, then I gave it to my g/f well ex when we broke up, cause she needed a car an i wanted to get rid of it..lmao, but as she said it has been driving perfect

[crumpdogg]

What kind of car is it? Mine doesn't have a MAF sensor. Get an ohm meter and a manual and check the TPS. Also, do you have standard or auto tranny? If auto, could be a speed sensor/ adjustment.

[mikew04]

Its a standard..
this thread and this one are about the same problem that i think im having, but there was no clear answer. what exactly is the auto air bypass valve, and what does it do? Im still thinking it has something to do with the ignition wires in the dash that i cut to put the relay in, not only bc of the problem im having, but also the fact that it just wont start sometimes. lights will come on, but the starter wont turn. its totally random. i cut both the starter wire and ignition wire in the dash bc i wired the relay to the ignition wire first, but the starter would still turn, so i then wired the relay to the start wire. i dont know why BOTH connections would go, but im going to redo these connections to see if the problem is fixed. but if this is not the problem, i would like to have as many ideas as i can as to what would be wrong. im only able to work on my car for like a weekend at a time, and its a real pain.
thanks again for any help
-mike