why is my car stalling when I stop?

rolltide

Registered User
I have a question I hope someone can help with. Just recently my 95 SC 5-speed with 102K miles developed a problem. When I stop at lights or other places, the RPM need drops way down below 500rpm and the car sometimes just dies which can cause problems because obvioisly I lose the sterring. It does not idle rough at all. It idles at around 7-800 rpm when the car is sitting still. Just happens when I shift down then put it in neutral and let it coast up to the light. The car just wants to quit and I have to start it back up quickly then it runs fine. Can it be a fuel pump or vacumn problem? Thank you for any help.
 
If you engine doesnt idle at around 1000-1200 RPM while the car is moving with the clutch in check your wire connector at VSS on the tranny.
Have you pulled the codes?
If not I recomend you do so.
 
stalling problem

The idle is not 1000-1200 rpm when clutch is depressed. Actually the idle drops down to around 500 RPM when the clutch is depressed between 1 and 2nd gear and neutral and 1st. That is when it tries to die and sometimes does unless I get on the gas. Funny thing is, my speedometer has stopped working also, so I had my VSS wire checked by a mechanic and they said it was good. Should I have someone else look at it.
 
Don't know about 5 spds,but when my aod did this I changed out the broken motor mounts and replaced w/solid ones..problem went away......may sound crazy,but it worked.So,check your motor mounts and see if they are good.
z
 
A partially unplugged or corroded ignition wire would definitely cause those symptoms as would a plug thats fouled or defective.
 
The VSS or wiring is the problem. Your eec is not getting speed info, so it cannot figure the dashpot settings correctly. This can cause the stalling at a stop.

Aaron
 
Pastera is correct. Either the wiring at the VSS is bad or the VSS itself is bad. The fact that your speedo stoped working proves this.;)
 
thanks so far

Ok. I will check the VSS. My mechanic checked the VSS wire (he even bought one from Ford and tested it and that did not fix the speedo problem. Great guy, he didn't even charge me for the part, he said he would be able to use it on someone's car. So if it is the VSS sensor, is that expensive and might it also fix the speedo. Thank you everyone for your inputs.

The wires and plugs are new.
 
The VSS tells the comp how fast youre going and then the comp displays that info at the speedo.
Could just be the wireing though, I'd make sure before I bought a VSS.:)
 
Rolltide

You first need to get a schematic of the speedo wiring for a 95. I only have it for the 89, so I can't help you with that.

Can someone post the VSS wiring for a 95?

Once I have that in hand I can help you trouble shoot the system if you have a VOM.

Taking your SC to most mechanics is like taking a horse to a gynecologist. These cars NEED someone who understands complex electrical systems to diagnose problems. Most mechanics easter-egg until they find the problem in these cars and it gets very expensive for you.

Aaron
 
stalling

I agree with Z90 sc-
Even after 20k....check the motor mounts.....
That did it for me.
The theory is that the knock sensor picks up the mounts banging,
and retards the timing.
Good luck
 
VSS problem

Just got my mechanic (not at Ford) to pull the codes. He got a 452-VSS/PCM input low. He did it for $15, because he knows I will bring it back to him. Problem is where do we go from here. He does not know a lot about these cars He said he already tried the VSS (aabout $20 part, right?) to try and fix the speedo. Now this new problem. What are the other options. Wiring maybe? It won't be internal to the tranny will it. These cars have speedo gears or a magnetic pickup
 
I think you guy's may be confused about the sensors.
This is the nuetral safety switch and it probably costs in the neighborhood of $20. This part is located above the shift linkage on the tranny.
This is not the sensor causing the problem and maybe this is the one he was looking at.
 

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This is the VSS and it is located on the tailshaft housing of the tranny. I dont beleive this part is only $20 but I could be wrong.
If I remember right its about $65. Anyway this is whats causing the problem.
But make sure he checks the wiring going to this sensor to make sure its good before buying a new VSS.
Could just be dirty wire connections at this sensor causing the problem.
 

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This is a side by side shot of the 2.
The VSS is much bigger as you can see. Everything below the retaining clamp on the VSS is inside the tranny so take that into account when looking for it. It goes in the tranny where the speedo cable usually goes.
 

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Lost my first post to file size.

The diagram shows a resistance of 220 ohms for the VSS. You should be able to measure the resistance and spin it slowly to see if it changes. I can't verify this because I don't have one in front of me.

Check the ground at the connector (black with white stripe)

Check for voltage at the signal wire (dark green w/white stripe) with a VOM (not a signal light) with key on/engine off. You should see some voltage there but I can't be 100% sure of the exact numbers with out a detailed schematic.

The obvious place for a wiring issue is somewhere between the secondary junction block and the sensor.

Aaron
 

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Problem solved

I bought a speed sensor connector from Ford and spliced it in and it actually fixed the problem. Big relief.
 
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