90 lumina speedometer drops and lacks power

[BigPhil215]

My 1990 lumina 3.1 runs good for the most part. sometimes while I am driving down the road at 60mph (not always 60mph somtimes 10 or just coasting at a red light) the speedometer will drop to about 5mph and the engine will lack power, if I let off the gas it will "surge" (rpm low then high) and sometimes stall. It will do this for about 15 min at a time and then run good between 20 min to almost 2 weeks, just when I think its doing good. Any advice for me??

[jeffcoslacker]

Originally Posted by BigPhil215

My 1990 lumina 3.1 runs good for the most part. sometimes while I am driving down the road at 60mph (not always 60mph somtimes 10 or just coasting at a red light) the speedometer will drop to about 5mph and the engine will lack power, if I let off the gas it will "surge" (rpm low then high) and sometimes stall. It will do this for about 15 min at a time and then run good between 20 min to almost 2 weeks, just when I think its doing good. Any advice for me??

This is intriguing, but more info is needed. Engine warm or cold? Weather/air temp at the time. How for do you drive before it begins? Will it do it multiple times, or just once, then it's done 'till the next episode? How many miles on it? How old is the fuel filter? Anything, even if it seems insignifigant could be the key to the problem. Need something to point me in a direction, anyways.

[kittenuta]

my lumina does it too...the tach starts to jump back and forth, and the engine will stumble just a bit. this happened just last night, and it's still doing it today. i'm not quite sure if has anytihng to do with the temp or weather, but it starts to do it when the motor and/or tranny are warmed up. i also hear this awful gringing like noise. i can't hear when i prop the hood up, but i can hear it inside of the car. i'm quessing main bearings, but i have no idea. i just hate that noise. please help...i've already spent so much money on her with other things, i don't want to spend much more

[BigPhil215]

Originally Posted by jeffcoslacker

This is intriguing, but more info is needed. Engine warm or cold? Weather/air temp at the time. How for do you drive before it begins? Will it do it multiple times, or just once, then it's done 'till the next episode? How many miles on it? How old is the fuel filter? Anything, even if it seems insignifigant could be the key to the problem. Need something to point me in a direction, anyways.

THE TEMP AND WEATHER DONT MATTER IT DOES IT WHEN IT WANTS TOO. IT DOSENT DO IT ALL THE TIME. BUT WHEN IT DOES IT DOES IT MULTIPLE TIMES. THERE IS 140,000 ON IT. DONT KNOW ABOUT THE FUEL FILTER....? SOMETIMES I CAN DRIVE IT FOR ABOUT 100 MILES SOMETIMES ONLY 5MILES.

[danh0ward]

Originally Posted by BigPhil215

My 1990 lumina 3.1 runs good for the most part. sometimes while I am driving down the road at 60mph (not always 60mph somtimes 10 or just coasting at a red light) the speedometer will drop to about 5mph and the engine will lack power, if I let off the gas it will "surge" (rpm low then high) and sometimes stall. It will do this for about 15 min at a time and then run good between 20 min to almost 2 weeks, just when I think its doing good. Any advice for me??

MIKE/OSH
My car does the same thing but i also noticed that the ac stoped working when the speedometer stoped.The fan still blows out air but it is not as cold as it is when the speedometer is working.Could be just because the car is running like shit when the speedometer is not working?But i have no ida.
I think it is something electrical because when it is not working and i restart the car the speedometer will be working sometimes.

[jeffcoslacker]

First of all, before you do anything else, check your battery cables, and the connection from there to the jump start post and power center.

I've seen that cause wierder things..

Make sure the battery to motor and chassis grounds are good too.

[jeffcoslacker]

I wonder if you guys don't have a problem with the VSS. I don't know how they affect it when they go bad, but just from what it is there for, it seems likely to me.

If anybody had one go bad, please speak up.

Kittenuta, mains rattle and knock when they go bad. I doubt that's what you hear. Grinding type noises with jerking would usually point to tranny slippage, metal on metal clutch packs or whatever else. What's your tranny fluid look like?

[danh0ward]

Originally Posted by jeffcoslacker

I wonder if you guys don't have a problem with the VSS. I don't know how they affect it when they go bad, but just from what it is there for, it seems likely to me.

If anybody had one go bad, please speak up.

Kittenuta, mains rattle and knock when they go bad. I doubt that's what you hear. Grinding type noises with jerking would usually point to tranny slippage, metal on metal clutch packs or whatever else. What's your tranny fluid look like?

I took off the vss and had auto zone test it.They said it was fine.But that would make alot of sents that it is the vss.Do you know if they can test good and still be bad because the car works sometimes.I would like to try a new vss but i dont want to wast $65.00 and still have the problem.

P.S. I DO NOT HAVE ANY RATTLE OR KNOCK.
THANKS MIKE/OSH

[cadgear]

Other than testing your connectors and wiring, not that I know of. The sensor produces an AC voltage, so you could hook up a voltmeter and prop the front of the car up, chock the rears, and let it coast in drive.

The original problem is pretty stumping to me as well..

[danh0ward]

Originally Posted by cadgear

Other than testing your connectors and wiring, not that I know of. The sensor produces an AC voltage, so you could hook up a voltmeter and prop the front of the car up, chock the rears, and let it coast in drive.

The original problem is pretty stumping to me as well..

Thanks for the info. I tryed it and the voltmeter read the same when the speedometer was and was not working.So I know that the vss is working.

Is there anything els anyone can think of that might help?
My problem is explaind on the top by phil.
I have been trying to fix it for three weeks and am geting frustrated!!!!!!!!!!
thanks again mike/osh

[danh0ward]

Originally Posted by danh0ward

Thanks for the info. I tryed it and the voltmeter read the same when the speedometer was and was not working.So I know that the vss is working.

Is there anything els anyone can think of that might help?
My problem is explaind on the top by phil.
I have been trying to fix it for three weeks and am geting frustrated!!!!!!!!!!
thanks again mike/osh

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