Help! Mustang wont start!

[MustangLover71]

Hi....Please someone help. I have 91 mustang 5.0, manual trans with about 181,000 miles. I was taking the car on errands and on the second stop, coming back out, the car would not crank. The starter turns over strong and continues to turn over strong. There were no previous symptoms. I have replaced battery, starter, fuel pump, fuel filter, distributor, and cap, spark plugs and wires all within the last year. Spark plugs had spark...yet I suspected Ignition coil and ignition module and replaced them both. The car still won't start. I then sprayed starter fluid into the intake, the car briefly cranked and turned right off. This has been the only time it cranked up to this point. It seems that we may have eliminated spark or have we?? Soo...then I checked the fuel line below and pressure seemed fine to the touch. I checked the valve on the fuel sending line. A plentiful amount of gas came out. It seems like I have fuel at the rail and spark but still no crank. Could this still mean fuel pressure problem?? I am also wondering if ECC computer is bad. I am really stumped here....even if you have a hunch throw it my way. This is my only car and it's stuck at a shopping center parking lot waiting to be towed for abandonment. Please HELP!!! Are there things that I can check before replacing the computer?? Thank for you help in advance.

[RPM427]

Pop the hatch and reset the fuel pump inertia switch. On older cars, these switches tend to be tripped a lot easier, sometimes even by slamming the hatch too hard. You could have some residual pressure in the lines, but the pump may not be working.

If you turn the car to the "ON" position, can u hear the pump working?

[MustangLover71]

Thanks for the response. OK, here is a little more for you to go on....

We had already checked the fuel switch in the trunk today, that didnt seem to be the issue.

Yes, when the key is in the on position, you do hear the fuel pump. We also had plenty of gas in the tank.

The car sure acts like it wants to start, just cant get it going It just wont kick over! Another weird thing was this happened after the car had been driving fine. It was so sudden. Hadn't been riding rough at all. Had drove it for about 10 minutes, parked, 5 min later got back in, started it without problem, drove another 5 minutes, parked it, 5 minutes later tried to start it, wouldnt kick in, and here we are.

We are pretty sure that we have narrowed this down to a fuel delivery problem, since we replaced the coil and modulator, and the spark is good. We know that when that starter fluid was sprayed into the intake that it fired up, very briefly, of course. So to us that says fuel delivery for sure.

The Fuel pump was replaced less than a year ago, and since we hear that engaging we are wondering if the problem lies with the regulator. We did find out that the regulator wasn't replaced or upgraded when the "after market" fuel pump was installed. Wondering if that is causing the problem.

We are finding there are no auto parts stores around here that will "Rent" out the fuel pressure gauge, and they want $40.00 to buy the darn thing. So we are thinking we may as well just replace the fuel regulator for $10.00. Not real sure. We have really dumped all available funds into this thing, and it is so frustrating because it is our only transportation. We are at our wits end

Hope it doesnt get towed from that parking lot before we figure it out

Thanks for your help and I appreciate any ideas on this nightmare!

[LX5liter]

Its pretty hard for the stock regulator to screw up. Check the fuel pressure, ($40.00 i know, but you have it for the rest of your life) and if its above 30# it should run. I would still suspect ignition, (TFI). A weak spark will ignite starting fluid, but not necessarily gas. Did you have a spark plug out to check the spark? Does it seem strong?

[MustangLover71]

Hi, thanks for the response-

We had suspected TFI Module as well. We actually replaced it first as it was one of those recalled modules on the fords. We also replaced the ignition coil. The spark seemed strong too. Thats why we then suspected fuel delivery trouble

The plugs were dry, so doesnt that mean the fuel is not getting up to them? We are probably going to replace the regulator today, simply because it should have been changed to an adjustable when the after market fuel pump was installed. The new fuel pump puts out more fuel....and everything we have read says a new regulator should have been installed to accomodate that. Because of this we are thinking maybe the diaphram on the regulator went bad. We are pretty sure that this fuel pump is still working, we can hear it when the key is ON. It was installed less than a year ago. We think we found somone who has a fuel pressure gauge we can borrow. We have replenished our funds here on these misc. parts and cant really fork out the $40.00 to buy the gauge right now. I could potentially buy one on Tuesday, but I hope we have the car running before then, or it might be towed for abandonment.

So, let me know what you think....We are at our wits end.

All advice appreciated!

[aar0s]

this may sound stupid but are you sure the injectors are sprayin'?
im knda in the dark as to how the injectors work but if you have good spark and fuel and compresion then it should fire up.

[MustangLover71]

HI aa-

Actually we think we DO NOT have fuel pressure. At least that is what we think because the plugs are dry, and by spraying that starter fluid in the intake, it DID start for a few seconds. So fuel delivery is all we can think of. Maybe we are going down the wrong path here?...

Not sure... how would we tell if the injectors are spraying?

Another clue that this was fuel delivery was we found out that the regulator wasnt upgraded when the after factory pump was installed less than a year ago...Everything we have read says this should have been done whenever upgrading to a higher output pump.

Turns out we couldnt get a ride down to the car tonight, so we will have to wait until tomorrow now So if you can let us know how to check this other stuff, we will def do it

I appreciate the help and advice!

[RPM427]

Hold a long metal object, like a screwdriver, to one of the injectors and hold the other end close to your ear. If the injectors are working, you should here the soleniods click open and shut while you crank.

[crazypete]

By "wont crank", do you mean it is not turning over or it wont kick in? I had an intermittent starting problem to the effect you descibed. It was nothing more than the main power terminal on the starter becoming corroded. It would crank sometimes, sometimes not. One day it stopped cranking altogether. I would never have found the problem if the starter wire had not started smoking!

For fuel pressure, just unbolt the regulator, place an inverted clear plastic cup over it, stand back and energize her! If it's a mighty spray, you've got pressure. If it's a little dribble, you dont. It's not very scientific, but it's free and convenient and lets you know if you are in the ballpark. As for the injector, unscrew a sparkplug, disconnect the coil wire and aim a flashlight into the cylinder and crank her. You will either see a little spray or smell it (or it will puff through the open plug hole). To diagnose a weak starting system due to bad ground or power, pull out _all_ the plugs and disconnect the coil wire. The engine will now offer no resistence to turning over (since there is no compression) . It will sound like a mingun and should tach at a constant rpm....like 400-500. If this works but it didnt work before, get some 80 grit and get down where the starter primary wire is, unbolt it, sand both the terminal and the wire connector and reattach. Do the same at the starter relay.

If all this fails, it's one of those silly modules, I had my TFI module go out on me a few years back for no apparent reason. I hate electronics, this is why I went carb (and I'm a programmer, I'm supposed to like computers).

Good luck!

[techsan]

Just a thought.

You may want to check the timing to ensure the timing chain hasn't stretched. With 180k on the motor it could have "jumped" timing, which may explain why it wants to crank but can't kick in. This could be the problem if your fuel pressure solution doesn't work. Good Luck.

[RPM427]

If the timing chain jumped only a tooth, it would probably still start. Even if it jumped a few, it would sputter and backfire. Your injectors are not firing for some reason. Chack all your fuses and relays for the EEC. Hook up a voltmeter to your injector harness and try and find out where the problem is. Its not a hard problem, just takes some time and patience.

[MustangLover71]

HI thanks for the replies,

Sadly, we still havn't figured this thing out We will gladly try the voltmeter, would have to borrow that from someone. Just hook it up to the injector harness huh?

Battery is finally starting to wear down of course, because we keep trying to start it to diagnose it. To respond to the earlier reply, since the day the car died, we have only been able to get the engine to fire up once, when we sprayed the starter fluid into the intake.

Didnt seem to see fluid in the vacuum hose today, but could smell some? We know there is fluid at the valve. We didnt get to replace the regulator today, didnt have the right tools to get to it
Our resources here are limited, don't seem to know the right people nor do we have access to the tools we need.

Cant seem to find anyone with a fuel pressure gauge that we can borrow, and like we said we are tapped out here...dont have the $40.00 to buy it. We are still leaning towards a fuel problem because it DID fire up with that starter fluid into the intake and we have spark. We didnt think it was a fuel relay problem, because we could hear the pump come on when the key is on, but we should check that as well. From what we understand that relay is under the drivers seat? Fuel safety switch in trunk has been checked.

We are thinking we may as well tow the thing home, to let it die in peace. Scared to tow it to a shop, where diagnosis and repairs could run so high, that our sweet stang would be held hostage for ransom

If we are missing something here let us know. Our car knowledge is limited and we don't always comprehend the terminology, so bare with us.

All of these responses are much appreciated. We are feeling pretty helpless here and your knowledge gives us hope.

Thanks again...
Mustanglover71

[MustangLover71]

OK, boyfriend came back, and the starter is fried now! Rechecked the fuel pump, it is working. Rechecked Filter, it is in great shape. There is gas at the valve. We still have spark, but I think battery is finally wearing down

So he rechecked the vaccume line at regulator for gas, cranked the car, no gas came out, went to turn the key off, and the damn starter wouldnt shut off, it just kept cranking! I am sure that this is because we have worn it out trying to start it...if this is more symptomatic of what our original problem could have been, someone let me know Boyfriend still thinks it is the regulator, we will have to test it tomorrow if we can find a fuel pressure regulator. I am wondering if that is not the problem now though since no gas came out of that vacuum line?

We have decided we will just have to borrow the money to tow the car here to our house, so it doesnt get impounded.

Especially now that it sounds like the starter and battery will have to be replaced as well.

Thinking the old girl has just died Praying for a miracle...

[RPM427]

Have you checked all of the fuses and relays assiaoted with the computer?

I'm almost sure its an injector/EEC problem.

[MustangLover71]

HI -

RPM- How do we check the fuses and relays associated with the computer? Is this where we have the computer codes tested?
We actually inquired about computer code testing from a shop, and were discouraged from it, they said the computers on these 91 mustangs dont offer much help as far as diagnosis, that they are inaccurate on not detailed. ??????

Sorry if that is not what you meant, but our car terminology is limited, think we need a translator

So, we have chewed through all our dough, and cant seem to find anyone in the metro Atlanta are to help, without getting it towed to a shop.

Hmmmm, at this point we could tow it home, and try to replace the starter our self (cause we know a shop will charge a lot) and then hope we can get back to diagnosing the original problem, whether that be a fuel regulator or injectors.

Aside from a computer test, the only way to test these injectors is to hold a metal object to it right? To listen for the injectors opening and closing?

All help is soooooo appreciated!
Mustanglover71

[RPM427]

When you go to crank the car over, does the "check engine" light come on for a few secs? If so, that means the EEC is alive and you haven't blown the power relay or fuse. If it doesn't come on, either your computer is fried or you will need to replace a relay or fuse.

You should check the fuel pressure from the shrader valve on the fuel rail, near the alternator. That will rule out any regulator problems.

Todays mechanics are used to hooking up a piece of diagnostics equipment to a newer car and having the computer tell them exactly what is wrong with the car and how to fix it. If you hook up a scanner to your computer, it will tell you if a sensor is bad, and also allow a decent mechanic to figure out exactly what is wrong with your car. Did you go around the car and check that all your grounds are still intact or a sensor hasn't come unplugged? It may be something as simple as that.

Good luck.

[crazypete]

EEC testing can be had for a voltmeter and a piece of wire

I could go into great detail on EEC testing but this page says it all. All you need is an analog voltmeter

http://www.corral.net/20anngt/images/test.gif

http://www.corral.net/20anngt/eec.htm

The codes arent terribly useful offhand because a problem will usually cause a cascade of errors but it's a good hint. That page lists the codes I think.

If it responds at all, the EEC relays are good. Else, the eec wouldnt respond. If you hear the fuel pump prime, the eec is already good...or at least alive, because the eec controls the fuel pump relay opening and closing. Hence, if the pump primes when you turn on the car, the eec sent it's little 1 second pulse.

I think the car would at least sputter a bit if even half the cylinders had working injectors (dont ask =P), so it is probably a central fuel delivery problem.

Back in my poor college student days, I had a fuel pump clog. I dropped the tank and removed the pump, switch polarity on the motor to make it run backwards and ran water through it and lo and behold, black sludge shot out. I emptied the pump, filled it with gas, switched the wires back and it ran great for another year. If they have a line clog, would it make sense to swap the wires on the fuel pump, suck gas back into the tank (ie...empty the lines), disconnect the fuel line at the clip fitting near the fuel rails, switch the wires back and maybe see what was clogging the lines shoot out? It's definatley a crazy pete idea but why not.

As for your starter, you toasted the relay on the driver's side fender near the battery. Maybe maybe beating it up a little will loosen the stuck relay switch inside. Cant hurt to smack it with a wrencha few times UNLESS you hear it click when you go turn the key to start. I think it's a $5 part.

Good luck bro

[MustangLover71]

RPM...Did I lose ya?

LOL. You mentioned the fuses and relays associated with the ECC, and we would like to check these. If you are talking about reading the codes, we just got information and code lists online tonight. Is that what you meant? When the care gets towed here we can give that a shot. Possibly tomorrow...

Won't you feel wise if it is a injector/ECC problem LOL

Also, I just want to be sure, when we cranked up the car so much last night, and then turned the key to off, it kept cranking. Had to disconnect the battery to get it to stop That doesnt mean we have lost the starter right? At first we thought maybe starter is bad now, but now we are hearing it is as simple as replacing a sylinoid? Is this true?


Thanks again for your help!

[MustangLover71]

Hey Crazypete-

I wanted to thank you as well for your information...Lots of stuff we can use when the car gets towed here. Now we just have to try to get our hands on some decent tools. We are a bit nervous about taking this on ourself, but we just cant afford a shop right now, and we dont have any mechanically inclined friends here in the Atlanta area that can help us.

I believe we will have it towed here tomorrow afternoon...

Hoping that with all of you guys backing us up, we can pin this down and get the stang back on the road

Thanks again

This is so hard to deal with when it is our only car, and we have very limited funds. Everyone on here has offered so much support and help... Gives us hope!

MustangLover71
91 Mustang LX 5.0
Has been stuck in a parking lot for 5 days now due to NO START
No previous symptoms, She is so sick

[RPM427]

If the starter kept cranking then the soleniod stuck, most likely due to heat by drawing so much current. Its a $5 part, so replacing it shouldn't be a problem. When you get it to the shop, ask them to hook a scanner up to it, write down all the codes it gives you, and post them here.

I think your computer is alive since the fuel pump is working, so checking the fuses/relays shouldn't be neccesary.

Have you checked the fuel pressure at the shrader valve? If so, what was it reading?