[ryanw]

when i first got my mustang about 12 years ago. i remember is starting up with in a second or two of turning the key with out having to step on the gas. Now when i turn the key it will crank over for a long long time with out starting. Ill turn the key off and then try again. with in three to four seconds it will start, maybe it starts a little quicker if im pumping the gas at the same time. when it idels it seems fine. i have notice that it doesnt seem like it has the same power it had a few years ago. i hadnt driven it other then a few trips around the block within the last five years. Ive changed the plugs, wiers, cap, fuel filter. i checked the omg on the coil. that seems fine. the fuel injectors have maybe 60000 miles on them. Im not sure whats going on. i havent checked my fuel pressure yet. thats my next step. Is any one else having this problem or had it. my car has 139000 miles

[91Mustang GT]

Originally Posted by ryanw when i first got my mustang about 12 years ago. i remember is starting up with in a second or two of turning the key with out having to step on the gas. Now when i turn the key it will crank over for a long long time with out starting. Ill turn the key off and then try again. with in three to four seconds it will start, maybe it starts a little quicker if im pumping the gas at the same time. when it idels it seems fine. i have notice that it doesnt seem like it has the same power it had a few years ago. i hadnt driven it other then a few trips around the block within the last five years. Ive changed the plugs, wiers, cap, fuel filter. i checked the omg on the coil. that seems fine. the fuel injectors have maybe 60000 miles on them. Im not sure whats going on. i havent checked my fuel pressure yet. thats my next step. Is any one else having this problem or had it. my car has 139000 miles

Starter could be going out maybe? Does it crank slow?

[ryanw]

No it doesnt start slow. i dont think its the starter. it has alot of cranking power. it has a little lack of horse power. i was thinking it had some thing to do with fuel. but what do i know

[Dap1991]

I noticed the same thing when i went to start up my gt after it sat for along period, but to me it seemed to got better once i drove it around for a little bit so idk

[ryanw]

ive just started driving the car a few months ago after paying back registration smog and all the other bull shi* that comes with keeping the car on the road. My starting problem is not getting any better. This is my second mustang. And im a big mustang fan. but little problems like this and it seems like the endless money and problems kind of reminded me why i put the stang out to pasture for almost five years and got a problem free toyota truck. But at the same time i missed my baby ( 91 mustang GT ) Its time to get her up and get her running right.

[ryanw]

Okay so i hooked up a fuel pressure gauge up and i only have 16 psi. from what i know i need to have 35-40 psi. this book i have said that if the fuel pressures low then its one of three things. a fuel leak, a bad fuel pump, or a leaking fuel injector. Well i can see that i dont have a fuel leak. so i guess its one of the other two. does any one know how to test for a leaking fuel injector or a bad fuel pump ?

[ddarkslayer]

I would start with the fuel filter then work to the fuel pump

[ryanw]

I just replace the fuel filter today. NO CHANGE.

[FastStang91Lx]

If you had a leaky injector, you probably would still see higher pressure. I would go with a new pump. And if so, I wouldn't go with a stock 88lph replacement. If you start to modify, hell even if you don't, I would go with nothing less than a 190lph or just run a 255 and be done. They can be had at a very reasonable price all over on the internet. Walboro is an extremely popular choice... I currently have one in my car.

[ryanw]

Ya. that was my plan just to upgrade to 255 lb fuel pump. If the pump is whats going on.

[FastStang91Lx]

Seriously... it's a good idea even if it's not. Especially if you plan to mod it.

[1slo5.0]

Originally Posted by ryanw Okay so i hooked up a fuel pressure gauge up and i only have 16 psi. from what i know i need to have 35-40 psi. this book i have said that if the fuel pressures low then its one of three things. a fuel leak, a bad fuel pump, or a leaking fuel injector. Well i can see that i dont have a fuel leak. so i guess its one of the other two. does any one know how to test for a leaking fuel injector or a bad fuel pump ?

The fuel pressure is bleeding off. The car won't run at 16psi. Check for leaking fuel injectors. Also check for fuel in the vacuum line to the fuel pressure regulator right after you shut the car off.

[ryanw]

But my car is running at 16 psi. I didnt think it would run with that low of fuel pressure but it does. Like i said at the top of the page, it is vary hard to start. Unless the fuel pressure gauge i just got is not reading wright. But i was thinking that my problem had some thing to do with FUEL. but ill check my vac line

[FastStang91Lx]

No, no, no. What he was saying is... pull the vacuum line off the fuel pressure regulator and check for any gas in it. There could be a tear in your diaphram inside it.

[ryanw]

Oh... Okay. Ill try that. Thanks

[Chris951]

if there's no gas in the fpr vac line then im going to say fuel pump is going bad.

My old 87 had a bad fuel pump and it took forever to start and would sometimes have a little backfire out the exhaust. I went and had the fuel pressure tested at a local mustang shop and it was at 8 psi. The car still ran, just not very good.

[1slo5.0]

Originally Posted by ryanw But my car is running at 16 psi. I didnt think it would run with that low of fuel pressure but it does. Like i said at the top of the page, it is vary hard to start. Unless the fuel pressure gauge i just got is not reading wright. But i was thinking that my problem had some thing to do with FUEL. but ill check my vac line

Try a different gauge. What kind of gauge are you using and where did you hook it up to?

[ryanw]

It was just some 30 dollar gauge from pep boys. I hooked it up at the fuel rail

[ryanw]

Well it looks like its the fuel pump. My father inlaw is a service writer / mechanic at a dealership, i brought it in to him today ang let him know what i found will the fuel pressure. and within an hour he called and said to order what ever size fuel pump i want in it. So i have a Walbro 255 lph on its way. I would have tried to replace it my self even though ive never done it before but i have a 6 month old son who doesnt give me any time to work on the car unless its a quick project. ha ha

[Chris951]

glad you got it figured out! told you it was the fuel pump lol