Speedometer/odmeter gone wonky along with engine light coming on

Joined
Jun 25, 2011
Messages
10
Likes
0
Points
0
#1
I have brought my "97 Ford Taurus into mechanics here and asked them to check why the speedometer keeps going from 100km down to "0" and stays there and today the RPM was up to 3 and the engine was reving and not driving properly. Also steering wheel feels like non powered (older models without power steering) and my mechanic is stumped. They tested all the electrical and it was showing fine for voltage so this is not the problem. They changed oil and the car has not been driven hard ,has almost a full tank so not the head gasket I wouldn't think. I have no clue why it is doing this though. For months the speedometer kept going from "100/120km" down to "0" then back to "100"" then down to "0" then fine for weeks at a time then does it again and then fine. Today was the first time the engine sounded this way and I could barely getter home from the mall. Tried using lower drive gear to see if the RPMs would come down but, to no avail. I am hoping someone there can answer this. I know the car is older, but low mileage and was in Red Deer owned by an older couple so in fantastic shape really with no rust even(no salt used out there) so it is really a quandry as to why it is doing this when the electrical showed all was fine and a tune up and all done only a few weeks ago,so I am baffled and bewildered. Anyone pls if you can answer this I would appreciate it. Thanks Lorri Speiran
 

billr

wrench
Staff member
Joined
Mar 12, 2007
Messages
6,638
Likes
88
Points
48
#2
Are there any trouble codes set (is the "check engine light" on? Does the CEL (check engine light) come on briefly at start-up (normal)? As this is a '97 a mechanic should be able to read live-data and do a lot better than "dunno"; your first step might be to ask friends and colleagues for referral to another shop, to get a "second opinion". FYI: changing engine oil can never hurt, but would have no effect on your problems. Similarly, fuel level in the tank can have no effect on the head gasket's condition. If anyone is touting those two ideas, keep clear of them!
 

Gus

wrench
Joined
Dec 8, 2006
Messages
2,421
Likes
1
Points
36
#3
VSS? Vehicle speed sensor? If car thinks speed is zero, won't shift and rpm's will be high as you step on the gas to make it go?

As previously asked, any codes?
 
Joined
Jun 25, 2011
Messages
10
Likes
0
Points
0
#4
No I am the one mentioning head gasket and all not the mechanic. They only tested the electrical as at that time my speedometer was going from 0 up to 100 back to 0 then stayed there then was fine for weeks then did it for a few minutes then fine again and he never charged second time I brought it in. As for the check engine liught. . . ya it has stayed on today the whole drive home which it has not done and yes I do know it will come on at start up normally.
So I am asking around to friends. . . . which one gave me this site to ask you all the questions.
One friend figured possibly the tranny cause the reving and yes the rpm's were high while I was only going maybe 20km to my knowledge as I had no speedometer working. I just went with the flow b4 the reving happened and engine light came on all at once with the steering stiff.
I mentioned head gasket cause it happened once b4 where i ran outa gas and sand got up into the engine caused head gasket to go in my cavalier yrs ago so I wondered if it was same prob but, I have never let gas get low. Yes I am a woman but, I do have brains and have done work on older cars with my dad. . . . not a girly girl so am understanding what you are saying. I have never used this site so was not sure how to ask or use it is all .

I would say after talking to two ppl and yourselves that it is either the thermometer cause that gauge is also not showing right at the moment. . . . . and or the tranny fluid and needs a good cleaning. All the oil was changed and the car is in great shape with low mileage so this just came up and I was thinking to get another opinion here to take into my honest mechanic here who like I said put the electrical tester on all and they came up fine. This is a small town so not many mechanics to choose from but with your expertise I felt I could maybe guide mine in the right direction. The engine light is on, the car is reving and almost goes to 3rpms while I am unable to make it go any faster than 20 clicks. . . . . . the steering gets stiff when turning tight corners like the old cars and that is all I can really say to give any info unless I take it in as I am not a licensed mechanic lol okidoki tyvm
 

billr

wrench
Staff member
Joined
Mar 12, 2007
Messages
6,638
Likes
88
Points
48
#5
Get the trouble code that is now set and post it. Most auto parts-supply places will do that for free.
 

nickb2

Wrench. Diagnostic Tech.
Joined
Nov 22, 2008
Messages
10,556
Likes
185
Points
63
Location
St-Hyacinthe, Quebec, Canada
#6
If trouble code comes back P0500, 501. Vss can be checked with resistance check, you want specs to be in the 190-250 ohms.

Also, you may want to check the actual gear and make sure it is not just worn down. Chewed in the center.
 
Joined
Jun 25, 2011
Messages
10
Likes
0
Points
0
#7
Ok now you have lost me, as I don't know what a trouble code is? If you can explain where it is to look for,then I can do this.
thanks everyone for your help. I truly do appreciate it.
 

Gus

wrench
Joined
Dec 8, 2006
Messages
2,421
Likes
1
Points
36
#8

Ok now you have lost me, as I don't know what a trouble code is? If you can explain where it is to look for,then I can do this.

I would say after talking to two ppl and yourselves that it is either the thermometer cause that gauge is also not showing right at the moment. . . . . and or the tranny fluid and needs a good cleaning.

No I am the one mentioning head gasket and all not the mechanic.
I mentioned head gasket cause it happened once b4 where i ran outa gas and sand got up into the engine caused head gasket to go in my cavalier yrs ago so I wondered if it was same prob but, I have never let gas get low. Yes I am a woman but, I do have brains and have done work on older cars with my dad. . . . not a girly girl so am understanding what you are saying. I have never used this site so was not sure how to ask or use it is all .


OK, you are not a girly girl, and don't take this the wrong way, but from these statements you made, your knowledge is very limited......you don't know what a trouble code is......I don't know who convinced you that sand caused a head gasket problem.....thermometer? Does this mean the car is overheating? Tranny fluid needs to be cleaned? Cleaning the fluid is not going to solve your problem....

You say you took it to a mechanic, and they put a tester on it and everything was fine? Was the car acting up at the time? Did they take it for a road test with you and did it act up in front of them? If it did, then go to someone else, because they don't know what they are doing....
 
Joined
Jun 25, 2011
Messages
10
Likes
0
Points
0
#9
Ok so I am stupid as a trouble code is not something I know. As for the sand up in the gas I dunno,this is what I was told in 1996 after I drove the car and ran outa gas and it ended up needing a new head gasket(I was told this so how am I to know what is rt or wrong when I am not a mechanic?)
Anyway you still never told me what a trouble code is so I can look for it. As for the car acting up. . . . . all it did b4 was the speedometer kept going wonky and they tested all the electrical, changed oil(yearly check up) and took it for a test drive but, the speedometer never did it for them so they still had no clue as to why it was doing this when all the electrical was fine.
They will now hear about the engine light coming on, the odometer going up to 3rpms and the speedomter acting all crazy once more. This is the first that the engine light and odometer did this so the mechanic was not aware as to this new revelation. Bad mouthing him doesn't make him a bad mechanic. . . . . when this stuff never happened til now how could he check for it. Gee wiz yes I do know about cars,can change a flat and not scared to try and work on things if I know where to look. I am not an expert but, for a girl I do know more than most. I am sorry you find it necessary to be rude. Must not have a happy life I guess or you would just have answered the question and not get cocky.
Now I am sorry I came in here thinking I would get some respect as I am asking all I know to ask and letting you know what has been happening to help me know what to ask my mechanic to check if you(so called expert) could answer my questions. I asked what this trouble code is bc I don't know and admitted I don't. I am not a mechanic,but don't need to be spoken to like I am an idiot. The cars now are mainly run on computer chip,but gimme and old car with the lifters visible and a flat tire and I have no fear to do things. . . . . . . I don't want smart ass answers tyvm for your time and I will ask my mechanic to look into the thermostat and also change the oil and filters and tranny.
I know about hockey,played baseball,curled and more,so as a woman I am not afraid to get down and dirty to do what has to be done. Thanks bud
 

billr

wrench
Staff member
Joined
Mar 12, 2007
Messages
6,638
Likes
88
Points
48
#10
When the CEL (check engine light) stays on it indicates the car's control computer has detected a problem and stored a code to help identify it. Every competent mechanic, even most DIYers, have a scan tool that connects to the car's electrical system and will read the codes; and most parts stores will also do it for you.
 
Joined
Jun 25, 2011
Messages
10
Likes
0
Points
0
#11
Thank you Bill for your kind answer. I called the mechanic and will wait to see if I can get it in Monday. I left a message telling him what is happening now with the car,so he will most likely do as you suggested as he checked all b4 but nothing showed,however now the engine light is staying on and it is reving in high gear. May be stripped gears(automatic) but the temp gauge is below the "C" and no smoke outa the engine,just high revs and I could not get it past 20 without it really sounding rough. I just took it easy to get it home and will do same Monday or get CAA to tow it to mechanic. I don't want to do more damage to it and thats why I came to you guys as suggested by a friend so that I could maybe look into things. As for the codes,I don't have the tool to check this. My dad is dead so I cannot ask for his help. I live with my 74 yr old Mom and am our only means of transportation so wanted to check all angles to be sure I am not driving it when I shouldn't at all. I took a chance coming in here so I thank you for your friendly answer. It means alot coming from a farm girl who just wanted to make sure I wasn't f'n up my car more.
Thanks BillR
Lorri
 

nickb2

Wrench. Diagnostic Tech.
Joined
Nov 22, 2008
Messages
10,556
Likes
185
Points
63
Location
St-Hyacinthe, Quebec, Canada
#12
Heres a picture of what I think is what is wrong with your car. The trouble code that will come back, should by what you have stated the symptoms are, be a code with these letters and numbers in it to identify the trouble area. P0500 or P0501. This is the VSS (vehicle speed sensor) circuit. If the nylon gear which turns around and thus giving you your speed indication by the amount of times it turns, is chewed up in the center, you will have your exact symptoms. You may also have an electrical problem with this sensor. It will cause same problems as a chewed nylon gear. Here are pictures of what I am talking about. It always helps to be wizened up about these things before heading into a garage. Now depending on the transmission you have, you either have a cable or an electrical signal sensor. The difference is that one indicating your speed mechanically by way of a cable, the other is by way of electronic signal. I suspect you have a electronic signal since your dash is indicating zero speed and your tranny won't shift out of first. In the ACE 1 PDF you will see both types of VSS,s.

This of course is assuming that is what the PCM has stored as a trouble code to light your CEL. PCM = powertrain control module.

In the third attachment, you will actually see what a actual FORD sensor gear that has worn down looks like for your car.

I hope this has been as clear as can be and will help you out.

I often find a picture is worth a thousand words.



[attachment deleted during maintenance]
 
Joined
Jun 25, 2011
Messages
10
Likes
0
Points
0
#13
Thank you very much Nick. Wow even pictures. . . . . now thats the kind of answer I needed. You explained it thoroughly as well as Bill and I am grateful for the info and pjotos as I like to learn about my car so I don't get taken to the cleaners too. Your photos were perfect. . . . as you said a picture is worth a thousand words and you certainly explained it fully for me to now see what and where and how to tell the mechanic what I want him to look at. They are competent. . . . . it's just that my car wasn't showing anything and no engine light b4 now. They told me as soon as it happened to bring it in and they would throw it on the sensor to see if they could find the problem but, it wouldn't happen often and usually when I was on the highway halfway to somewhere or on a wknd when they are not open. . . . . so now tomorrow I can take it in with my own knowledge which helps a damsal in distress. :thx so much
I will get back to you once I take it in and let you all know what it was exactly. . . . and again Nick thanks so much for being considerate of my situation. Means alot when someone can be kind and give me a good answer. Toodles fer now.
Lorri
 
Joined
Jun 25, 2011
Messages
10
Likes
0
Points
0
#14
Hey Nick just wanted to let you know you were right about it being the speed sensor needing to be replaced. Whew at least it did not cost an arm and a leg to fix it. They are a fair mechanic shop and run by a reputable person, was just that nothing showed til my engine light came on for them to get a trouble code. So yup thats what the problem was. Thanks again for your awesome help. Means alot. :D Lorri Speiran