yurizx6r

Hey guys, this may be long but I'll break it up.

My 93 5.0 seems to be stalling when I'm coming up to a stop and I push the clutch in. It does not do it every time, but it's done it 3 times in 100 miles. The car starts right back up, and shows no other signs of anything wrong at all. Thoughts?

yurizx6r

Some side notes:

I just recently swapped my intake manifold, so I unplugged a bunch of stuff, but I was careful to put all the grounds back in.

I also recently stalled due to my HID ballast taking a crap. The voltage meter was going up and down, but then I realized it was only doing that when the headlights were on. I cut the HID kit out and that solved the voltage meter bobbing, but I'm not 100% sure if the two are related or not. Each time the car has stalled the head lights have been on.... but once again correlation does not mean causation.

One last thing, I have been experiencing a "popping"/clicking noise and feeling the clutch pedal every time I push it all the way down. However, it's been doing this for a few months and it's been stalling only the last 100 miles. Once again...........related!? Who knows. Could this be the clutch/starter safety switch? What are the symptoms of a bad one?

dawson1112

Stalling when you come to a stop and push the clutch in could indicate a faulty VSS.

They are supposed to help keep the rpm from rapid drop on the MAF cars.

yurizx6r

Vehicle speed sensor? Actually I just took it for another drive and once again the voltage gauge went toward the negatives. The headlights were on because it was raining, but as soon as I shut them off it went back to the positive.

dawson1112

The older SD (speed density ) cars only used the VSS ( Vehicle Speed sensor )for cruise control so it wasn't really tied into the eec . The reason is because SD used a MAP ( manifold absolute pressure sensor ) so when you let off the gas it took an instant vacuum or pressure density reading , with MAF cars when you let off the gas the reading is less instant and can cause the IAC to hiccup for a moment , hence the VSS if the car is moving and the clutch is pressed in the eec automatically opens the IAC a bit and raises idle. Once the car comes to a complete stop or falls to a certain mph the eec levels out the idle .

It sounds like you have a voltage issue that needs to be addressed though. How ever my voltage gauge drops as well at idle when ever I put the lights or ac blower on. But I think my issue is more related to having underdrive pulleys. You could be having an issue with your alternator . I would pull the alt and take it to have it tested some place, if its week you might want to consider doing the 3G alt conversion. Its what came in place of the 2G when they started the sn95 model year. The stock 2G alt puts out a wimpy 65 amps , fine for running stock equipment, but when HID lights, and after market stereo and amp are used they just don't seem to hold up long.
A 3G alt will start at about 95 amps I believe but are usually in the 130-160 amp range. Much better power with these , and is a popular mod on the fox body mustangs....

It is quite possible that the use of HID lights caused the stock alt to burn up, and is likely the reason the voltage was jumping up and down with the HID lights on.

yurizx6r

I had the alternator tested twice within three days. Both test came out fine. The voltage meter is perfect/normal when the headlights are off. Once I turn them off the voltage meter and the RPM's seem to go up and down together (at the same time) until finally the voltage meter reads more toward the negative. When the headlights are on, it seems the RPM's are not as stable. I just realized this today. Once again, maybe there's a short in the head lights, but I'm not totally sure on this one.

dawson1112

Pull the head light switch and look at the inside of the plug for broken pieces , burnt spots or loose connections.

yurizx6r

Do you think it's possible that could be the cause of it stalling? The voltage meter makes sense, but I wondering how it is drawing so much power that the rpm's and voltage meter are side by side going up and down.

yurizx6r

Would you also happen to know how to test the grounds with a voltage meter?

robotnix

interesting because I have a similar problem.
so at stop light my rpm would go 900-700, 900-600, 900-500, stalled.
today I removed the air filter and cleaned the housing and replaced the filter.
removed the ICA and cleaned with carb cleaner.
just went out all seemed fine but as soon as I got home and touched the button to close the windows my voltmeter went down and my car idle started to play again...

I will be following this... I just don't understand how on a OEM car, closing the window while on idle can cause this... unless alternator is going bad?