ugh my wife's car is misbehaving.

[waggy]

Originally posted by: funboy42
Sounds like several things waggy.
They don't use cables anymore to the best of my knowledge unless you have really old car. So maybe the sensor for the spedo is coming unplugged or shorting out, or completely wacked. And since a lot of sensors may use that one to determine the speed, spark plug advance, fuel to use, throttle position, and so on the car may run like crap. Hence the check engine light.

Another one is like mentioned ia an above post and that is if it is throwing a tranny code (hence the check engine light as well for this), the newer cars will put the trans into whats called "limp mode". The car wont shift right or wont shift out of second and will have to floor it to get it to speeds of 45-50.

Since it is a 97 escort its a mazda build so I would prolly go with the spedo sensor shorting out/bad since a lot of other sensors rely on that one to determine how to adjust for other things. Im not 100% sure it would have a limp mode for that trans though or for that year. The 3 years I worked for ford the only real problems the escorts of that year came in for was vibration in the steering wheel from a poorly balanced 4cyl engine and timming belt breakage. Now there is a slim, super slim chance, it may of broken a tooth on the belt. It would cause it to run like you mentioned but it would be doing it all the time since slipping. Either way walmart sells a OBD II code reader for $50 which will pay for itself the first time you use it. I highly recomend you pick one up. If anything at least you can clear the code yourself and see if it makes the car run better and if not will know what ever shop you take it to is bull sh1tting you for you will know what the light is on for.

yeah thats what a guy said who i usually take the car to. pitty he is so busy he said he wouldnt be able to look at it for 2 weeks.

i looked at walmart for a reader. cheapest they had was $99 the guy said they do have cheaper but won't have any in stock for a week. GRR.

 

[AgaBoogaBoo]

Originally posted by: radioouman
Bad computer.

Must be running Windows ME

</obligatory joke>

 

[iamwiz82]

Originally posted by: waggy

Originally posted by: funboy42
Sounds like several things waggy.
They don't use cables anymore to the best of my knowledge unless you have really old car. So maybe the sensor for the spedo is coming unplugged or shorting out, or completely wacked. And since a lot of sensors may use that one to determine the speed, spark plug advance, fuel to use, throttle position, and so on the car may run like crap. Hence the check engine light.

Another one is like mentioned ia an above post and that is if it is throwing a tranny code (hence the check engine light as well for this), the newer cars will put the trans into whats called "limp mode". The car wont shift right or wont shift out of second and will have to floor it to get it to speeds of 45-50.

Since it is a 97 escort its a mazda build so I would prolly go with the spedo sensor shorting out/bad since a lot of other sensors rely on that one to determine how to adjust for other things. Im not 100% sure it would have a limp mode for that trans though or for that year. The 3 years I worked for ford the only real problems the escorts of that year came in for was vibration in the steering wheel from a poorly balanced 4cyl engine and timming belt breakage. Now there is a slim, super slim chance, it may of broken a tooth on the belt. It would cause it to run like you mentioned but it would be doing it all the time since slipping. Either way walmart sells a OBD II code reader for $50 which will pay for itself the first time you use it. I highly recomend you pick one up. If anything at least you can clear the code yourself and see if it makes the car run better and if not will know what ever shop you take it to is bull sh1tting you for you will know what the light is on for.

yeah thats what a guy said who i usually take the car to. pitty he is so busy he said he wouldnt be able to look at it for 2 weeks.

i looked at walmart for a reader. cheapest they had was $99 the guy said they do have cheaper but won't have any in stock for a week. GRR.

You can rent readers for free from Autozone or any other major auto parts store I have ever been to.

 

[fbrdphreak]

Go to Adv Auto/Auto Zone and have them pull the codes. They will give you numerical codes which you can look up online to see what the computer is telling you. Then go from there.

 

[waggy]

Originally posted by: fbrdphreak
Go to Adv Auto/Auto Zone and have them pull the codes. They will give you numerical codes which you can look up online to see what the computer is telling you. Then go from there.

i would if the car was releiable enough to get to teh store.

 

[BoomerD]

Originally posted by: Zenmervolt
The issue is electrical somewhere. The speedo probably gets its reading from the ECU rather than from the speed sensor directly. As has already been said, if the speed sensor is borked, it will affect several other things. Find out what the OBD II code is that is causing the check engine light to come on and go from there.

ZV

QFT...something like a bad sensor, bad computer, or something in between. Nothing mechanical will cause the speedometer fluctuation AND the other symptoms.

 

[hoorah]

Some replies here are right on, others not so much....

A bad alternator can cause similar symptoms to this, as the battery voltage gets low the sensors will wig out, it won't have enough spark, and the car will misfire. However, if this were the case, the battery would be dead, and you wouldn't be able to start the car afterwards. Pretty sure this is not the case.

I'd guess the trans speed sensor because its a combo of a false speedo reading and incorrect gear selection, but you gotta get those codes read to be sure.

I would DEFINITELY recommend getting your own scanner or at least finding an Advance close by. For $50, you'll never have to pay for an $80 "Electrical Diagnosis" again. I know I've seen the pocket sized readers at Discount Auto for $49.99

 

[OrganizedChaos]

my guess is the VSS is shot and the computer is putting the car into limp mode. the computer probably dosne't have a clue as to when it needs to downshift and thats why its lugging.

 

[waggy]

damn they are trying to get a lot.

they want
speed sensor $250 (wich is what makeing the driving probs)
tie rods $215 (wich my BIL just did last summer)
rear coils $420

sheehs

 

[Vette73]

Do the speed sensor first. It should run you around $60 or so at Advance auto. Very easy to replace in most FWD cars as it is held on by 1 bolt.

Do that first. Disconnect the battery, replace speed sensor, and then reconnect battery and drive.

Report back after that.

 

[waggy]

Originally posted by: Marlin1975
Do the speed sensor first. It should run you around $60 or so at Advance auto. Very easy to replace in most FWD cars as it is held on by 1 bolt.

Do that first. Disconnect the battery, replace speed sensor, and then reconnect battery and drive.

Report back after that.

hmm we were told it was in the transmision.

 

[dmcowen674]

Originally posted by: waggy

Originally posted by: Marlin1975
Do the speed sensor first. It should run you around $60 or so at Advance auto. Very easy to replace in most FWD cars as it is held on by 1 bolt.

Do that first. Disconnect the battery, replace speed sensor, and then reconnect battery and drive.

Report back after that.

hmm we were told it was in the transmision.

Usually on the side of the transmission. It should be easy to change out.

 

[bctbct]

speed sensor, transmission is in the limp mode and will not shift past second gear. mine cost $35 from the dealer. Much like a spark plug, screws into the side of the transmission. Is this a chrysler?

There is a speed input and a speed output sensor.

 

[Shawn]

yeah, replace the speed sensor, and only the speed sensor. then report back.

 

[iamwiz82]

Originally posted by: waggy
damn they are trying to get a lot.

they want
speed sensor $250 (wich is what makeing the driving probs)
tie rods $215 (wich my BIL just did last summer)
rear coils $420

sheehs

If you are at mechanically inclined grab a Haynes and a wrench and replace the VSS yourself.

 

[Bacstar]

My chrysler had the speed sensor go bad, and as another poster said, the transmission goes into limp mode. Your tranny is pretty much stuck in 2nd gear or whatever.

I pretty much swore off getting my hands dirty, so I had the dealer replace it for a couple hundred bucks.