Not necessarily. That could happen if it were completely shot, or it wouldn't even start at all. What I read about the Mach issue was that their pumps were heating up while driving and sticking randomly (irritated by various issues like volume requirement, fuel level, gunk on the sock). Once they had a couple seconds to cool down, they would kick right back on.

I had an old MGB with rust in the tank that would do the same thing but it did it consistently. Would start, idle, and drive fine under 25 MPH. Anything above that and it would suck up some rust into the line and dam up near the pump and shut it off. Then it would wash back to the tank. Start right back up and do it all over again. In King's case I am speculating that his pump is heating up and causing the issue and then cooling back down (with no voltage to the pump and sitting in a tank of cool fuel) so it goes away quickly and starts back up.

They supposedly have already checked the pump and everything checked out fine (a week ago anyway). It's not throwing codes or anything.

The scumbag I talked to said that it's probably my IAC again. I guess they didn't replace it before, they just cleaned the excessive carbon deposits off of it. So they're going to drive my car all day and see if they can replicate the problem and then we'll go from there.

I have ZERO dollars to spend on this, so if they come back telling me that it's going to cost x amount of dollars then screw this. Like Sunshine said, I love this car but it's not worth my life.

how does the steering will lock if your key is still in the ON position...oh wait maybe because you lost power steering you couldnt turn the wheel anymore. than you put in that your radio turned off...which brings me back to thinking that your cars problem is most likely electrical. hope the ford nerds can figure it out

I will gladly trade you my fully operational 98 v6 for your quirky mach 1

Yeah I'm starting to think that it doesn't fully lock, but when you're used to power steering it feels like it. It doesn't make the locking sound, so that's probably not what's going on.

my 87 automatic ranger used to do the same thing. I would be driving at like between 40-60 mph and when I would take my foot of the gas it would sometimes shut off. Just like you said you lose power steering and your brakes pump up and get hard. But mine would take a couple trys to get restarted sometimes and then sometimes it would restart right away. I can't tell you exactly what fixed it but I replaced the IAC, fuel pump, fuel pump relay, and and fuel filter and it hasn't done it for years.

My thoughts are this. If it was your IAC, it should do it more frequently at varying RPMS and you should be able to easily replicate the issue. When my last one went out, I noticed it at first when I would back up and press in the clutch with the wheels turned, it would die. It eventually got to the point that it would never come down from 1200RPM at idle. Replaced IAC ($70 and 5 minutes of time) and problems went away. I did try cleaning it out and it didn't do anything.

This issue seems to me more sporadic. I know you said they checked the fuel pump but was it to see if it simply worked or not? Or did they log your pressure at varied RPMS and under load to see if it stayed within range? Get it under 1/4 tank of gas and have them look at it.

Also, if it does it to you again and your pump is OK, there should still be pressure in the fuel rails after it stalls out. Next time it stalls. press your schrader valve but keep something over it so you don't get gas in your eye or on your paint or hot engine. It should squirt out with some decent pressure behind it. If no pressure or it dribbles, then you have a fuel issue.

You want a 2000 gt? We can trade. P.s. I agree with Cobra1923, fuel pumps gotta be doing it.

it has to be electrical, fuel pump failure wouldnt turn power steering off.

No thanks on the gt...

And call me an idiot, but what's a shrader valve (I'm going to Wyotech in January so I can understand more of this stuff)

I'd still put my money on the IAC, seems to me if it was the pump, it would fail under load more so than at idle, not being about to supply enough fuel. Maybe the dealership has an updated calibration for the car?

When the motor stops running, so does the power steering pump, even worse is if the car has hydroboost brakes, which runs off the power steering pump also, so it makes for a bad day ;) been there, it sucks

like the valve on the tires, there should be one on your fuel rail

that's cool, I learn something new every day...

So the car has been at the dealership for 23 hours and 15-ish minutes and still no word. I'm starting to question if they know that I'm not paying for any of this...I don't have the money

The most '03 cars and '04+ Cars do not have a sharder valve on them anymore. I would look into a fuel or tune problem as well. I would have checked the fuel pressure sensor on the fuel rail, the pump, and then move from there.

Well supposedly they retuned my car last week, so I doubt it's got anything to do with that.

Got the car back today. The dealership said it's the clutch. Sure the clutch isn't in the greatest of shape, but I assure you it's not the clutch. So we're taking it to the dealership I bought it from on Monday to have them check it out too and get another opinion.

Took it to the pontiac dealership in town because they've got a GTO I've been interested in, but they quoted my trade-in value at $12,000 which would put me $8,000+ behind on my car loan. So getting the GTO which costs less than my car would actually give me bigger car payments...something I cannot afford.

that's the nature of the car dealerships right now. give people the run around and charge them a crapload of money. i would just buy another fuel pump and replace that. purge all the fuel lines, replace the IAC. WITHOUT the dealerships.

Forget the stealership. It appears they are just clueless and are naming parts. Do the work yourself. Plus, don't go to GM, Ford muscle is always superior.

your lucky to get 12 for your car. do it.

he's 8 grand upside down...your financial advice is just as good as your driving skills.

He IS lucky to get $12k for a trade in, especially considering how the economy is going.

...you really are an idiot, aren't you?

I would love to do the work myself, but there are two problems with that. One being I don't have the money for parts, another being that I don't know how to fix it (reason why I'm going to Wyotech in next month)...hell, no one even knows for sure what is going on.

Well, I have no idea how you have money for the stealership then.

As far as not knowing what to do, this is a Mustang forum right? You have people here who can guide you through. This is one of those problems that can be tricky to solve but you will never know the source of the problem until work is actually done to it. Sounds like the stealership just charged you for donuts and coffee for the tech guys.

Yeah that's probably all they did.

...we're taking the car early tomorrow morning to the dealership I bought it from 20 miles away in 4'' of packed/icy snow. Hooray!
my dad said that he'll take care of the repair costs which is really cool of him because I've paid for everything myself so far. Hopefully this dealership can either fix my problem or swap out my ride for another they've got without raising my monthly payments. Both I think are highly unlikely.

Wish me luck guys and gals.

Good luck.

If anything put it on ebay, you'll get more cash there.

I can't spend the time to private sell it because I leave for college three weeks from yesterday, and my parents don't want me swapping rides while I'm away. I'm just hoping this dealership actually fixes the problem this time around. I can't keep running in circles like this...I feel like a retarded nascar driver that doesn't know when to stop.

Instead of the dealership, have you considered local shops instead? Most mechanics that work at local shops have been around the block a few times and have seen more than the recent grads dealerships employ.

Funny story actually...we've got two shops in town. One ruined the electrical system on my moms old eclipse, while the other had a mechanic that "accidentally" drove into the side of my old Ford Bronco. The dealership may not be fixing my problems, but they sure as hell aren't making them any worse.

Okay so I got a call from the stealership today...they couldn't re-create the problem (they couldn't get the car to shut off), so we're picking it up tomorrow and they didn't do anything.

Hooray! Another $100 down the drain!

...car still broken

Here's another thing you can do. Get a good scanner that can record data and while driving, hit record and replicate the conditions that shut the car off. Go back to the stealership and show them the recorded results. If they are still clueless, don't ever go there again.

They decided to replace to IAC instead of clean it this time. I thought the dealership in town replaced it but when this other dealership called they told them that they cleaned it those f'ing liars. If that doesn't work, I'll stick an f'ing christmas sign up all of their a$$es.

Okay, so I got a call lastnight saying that the car was done and I could come pick it up in the morning. Unfortunately I'm out of town for the holidays, so I'll pick it up on Monday or early Tuesday morning. Hopefully this is FINALLY over, if not then don't be surprised if my car ends up in a ditch just so that I'm forced to get a new one...haha

good luck with that man. hopefully they fixed it.

Picked up the car today (or yesterday I guess), and it's a ton better. I tried and tried to get it to stall and act up and so far nothing. So I'm very pleased. They ended up fully replacing the IAC this time around instead of telling me they replaced it like the other dealership. So all is good for now. I wouldn't go to the extreme of saying this whole deal is over yet, because I don't want to jinx it, but I'm very confident that it's almost there if not there already.

good to hear that....having the steering wheel lock up on ya can make you kinda crap your pants.

the hood flying up will also make you crap your pants.. i know from experience.

That's because you fail.

Anyway, that f***ing problem happened again...All of this work, all of this money and it happened again! This time I don't have the money to squeeze out into it, and I can't trade it in with the crappy economy because I'd be stuck with a butt load of negative equity. So I'm sticking to it, going to do that DDX512 install tomorrow morning if I've got the time.

Maybe it's time for a 2v swap ;)

As mentioned, do the work yourself. You already have people telling you the pump may be going so replace the pump. Don't worry if you are clueless how to do it, people will tell you the steps and help you out. If you are scared to tear into your car now before school, no offense but school is not going to be easy for you then. You have to realize that either you are going to be dropping cash at dealerships who are clueless at the problem or you can save cash, and do the work yourself for something most people here feel is the problem. Your choice.

I agree with bassman97 and the others. I think it could be something in the fuel delivery. The steering wheel lock up - I am not sure of because as long as you don't turn the key off it shouldn't lock up, you would just loose your power steering. As for the part of taking it out of gear or when you press the clutch it takes the load off of the motor - which if there is a fuel delivery issue - it is sensing that there is a decrease in the load which make the motor de-fuel or cut fuel delievery (idle down).

One question you said you stay at a constant speed does your car have cruise control and if so do you use it?

Because there is something else I do remember my friend had in his Mustang that is really similar to yours - minus the steering issue - His would die out or die totally and he took it to the dealer as well as a number of shops and still didn't have a solution.

So out of frustration he ended up taking it to a local guy who worked on race cars. The guy went through the entire car and found that because of the cruise control the part of the ecu that controls the fuels delivery was not functioning as it should - don't remember the exact term or fix. The way the guy explained it was the car could not self adjust to de-fueling after the car had run at a fixed speed for a giving length of time.

My friend then ask well how did you know and not the shops. The guy had put the car on a dyno and set the cruise control. He said after about 25 min - he shut the cruise control off by stepping on the clutch and the car lugged and died. He said that the cruise control was trying to either stay on or come back on - I don't remember. He said it happens when cruise controls go bad or are going out. '

This might not be close. But it is worth a shot to try and take a look at. My old blazer also had the same problem it was an automatic but when I would disengauge it the truck would die after it had been running for awhile.