2000GT runs but won't start on it's own - Mustang Forum

PYRT'00GT · 12-17-2011, 09:31 AM

My 2000GT was down for a while and after I got it all repaired it wouldn't start.
I got it to start using starting fluid. It runs great after it's started.
Could it be the fuel pump? I would think it would not run at all if the fuel pump failed.

87'hybrid · 12-17-2011, 04:14 PM

Can you hear it prime when you turn the key to the on position?

modo · 12-17-2011, 06:20 PM

pull the coolant temp sensor harness off (the one going to the computer) then try to start it. sounds like you have a cold start issue and the first thing i would look at is that sensor.

cold motor with colder ambient temperatures needs a larger initial injector pulse and if the coolant temp sensor is not reading correctly that might not be happening. by pulling the sensor harness off the computer should assume its below 0 and throw a ton of fuel in.

PYRT'00GT · 12-18-2011, 04:09 PM

Quote:

Originally Posted by 87'hybrid

Can you hear it prime when you turn the key to the on position?

No

PYRT'00GT · 12-18-2011, 04:10 PM

Quote:

Originally Posted by modo

pull the coolant temp sensor harness off (the one going to the computer) then try to start it. sounds like you have a cold start issue and the first thing i would look at is that sensor.

cold motor with colder ambient temperatures needs a larger initial injector pulse and if the coolant temp sensor is not reading correctly that might not be happening. by pulling the sensor harness off the computer should assume its below 0 and throw a ton of fuel in.

Hmm...I'll have to try that. But I don't hear any buzz when I turn the key

87'hybrid · 12-18-2011, 04:26 PM

You should hear that buzz either way.

modo · 12-18-2011, 05:49 PM

Quote:

Originally Posted by PYRT'00GT

Hmm...I'll have to try that. But I don't hear any buzz when I turn the key

what? you said in the original post that it won't start initially but after hitting it with starting fluid it starts and runs fine. or did i read that wrong?

if the motor is running then the fuel pump is fine. if the motor will not start when cold and it is cold out (ambient temp) then its the cold start tables in the computer which would be the coolant temp sensor

PYRT'00GT · 12-20-2011, 06:05 AM

Quote:

Originally Posted by modo

what? you said in the original post that it won't start initially but after hitting it with starting fluid it starts and runs fine. or did i read that wrong?

if the motor is running then the fuel pump is fine. if the motor will not start when cold and it is cold out (ambient temp) then its the cold start tables in the computer which would be the coolant temp sensor

You read it right. What I was saying was I don't hear the buzz from the priming when I turn the key. It won't start until I hit it with starting fluid. Which, now that I think about it, if the cpu doesn't know it's cold, it's not gonna prime it.

03RedFireGT · 12-20-2011, 06:21 AM

The fuel pump will ALWAYS kick on when keyed on. No matter the temperature to ensure there is pressure at the rail. The engine needs ~30psi (correct me if wrong) for the engine to properly fire. My 03 would still run (like sh!t mind you) when the pump died as it was siphoning fuel on its own. Once you get it running is it running as if there's no problem or is it missing and bucking?

Put a pressure gauge on the schrader valve on the rail and see what kind of numbers you're getting.

MySlow2002GT · 12-21-2011, 04:37 AM

Quote:

Originally Posted by PYRT'00GT

Which, now that I think about it, if the cpu doesn't know it's cold, it's not gonna prime it.

PYRT'00GT · 12-21-2011, 07:26 AM

Am I misunderstanding something?

87'hybrid · 12-21-2011, 03:59 PM

Some of us think it's the fuel pump, others think it's the temp sensor.

PYRT'00GT · 12-21-2011, 04:35 PM

Okay, I'll test the coolant temp sensor first then the FP pressure. But IMO if it is a prob with the temp sensor then the FP won't put out the pressure. Maybe.
Thx for all the input. I'll be back

MySlow2002GT · 12-22-2011, 02:48 AM

Quote:

Originally Posted by PYRT'00GT

But IMO if it is a prob with the temp sensor then the FP won't put out the pressure.

modo · 12-22-2011, 10:03 AM

Quote:

Originally Posted by MySlow2002GT

:90gt:

PYRT'00GT · 01-04-2012, 10:23 PM

Quote:

Originally Posted by 03RedFireGT

The fuel pump will ALWAYS kick on when keyed on. No matter the temperature to ensure there is pressure at the rail. The engine needs ~30psi (correct me if wrong) for the engine to properly fire. My 03 would still run (like sh!t mind you) when the pump died as it was siphoning fuel on its own. Once you get it running is it running as if there's no problem or is it missing and bucking?

Put a pressure gauge on the schrader valve on the rail and see what kind of numbers you're getting.

Okay, did not do a pressure test. Took it for a spin after changing the worn out spark plugs. Won't run for shiat when pushed, so I suspect it is the FP. Any suggestions on a specific replacement pump. Nothing fancy, I haven't done much to it performance wise and don't plan to in the future.

87'hybrid · 01-05-2012, 04:01 PM

I suggest you get the whole pump assembly, and not just the pump. I changed just the pump in my '87, and 200 miles later acted up again. Turned out to be low voltage through the old wire harness.
http://www.autozone.com/autozone/par...0626_200274_0_

This should work ok. There are better pumps for a little more $$ though.

03RedFireGT · 01-05-2012, 05:05 PM

255lph SVT Focus pump. Not gonna cost you anymore than a stock replacement. Go through a dealer, Tousley Ford is my goto for great prices. Don't trust a VatoZone unit. Put a pressure gauge on the rail and check all your fuses to ensure it truly is your pump that is bad.

PYRT'00GT · 01-15-2012, 05:52 PM

Any reason I shouldn't purchase this on from an online aution site

87'hybrid · 01-16-2012, 04:04 PM

That doesn't come with the assembly or gaskets and hose clips you may need. But that is a decent pump at a good price....

12-17-2011, 09:31 AM	#1
PYRT'00GT Perpetual Monthly Income Join Date: Aug 2000 Location: Displaced Posts: 350	2000GT runs but won't start on it's own My 2000GT was down for a while and after I got it all repaired it wouldn't start. I got it to start using starting fluid. It runs great after it's started. Could it be the fuel pump? I would think it would not run at all if the fuel pump failed. __________________ www.TheGlobalNetwork.com/muddybark[/COLOR]]TGN

12-17-2011, 06:20 PM	#3
modo That Guy Join Date: Jan 2002 Location: In a house Posts: 9,804	pull the coolant temp sensor harness off (the one going to the computer) then try to start it. sounds like you have a cold start issue and the first thing i would look at is that sensor. cold motor with colder ambient temperatures needs a larger initial injector pulse and if the coolant temp sensor is not reading correctly that might not be happening. by pulling the sensor harness off the computer should assume its below 0 and throw a ton of fuel in. __________________ 93 GT 66 Coupe

12-20-2011, 06:21 AM	#9
03RedFireGT Registered User Join Date: Jan 2004 Location: Corn Fields of Central Illinois Posts: 5,073	The fuel pump will ALWAYS kick on when keyed on. No matter the temperature to ensure there is pressure at the rail. The engine needs ~30psi (correct me if wrong) for the engine to properly fire. My 03 would still run (like sh!t mind you) when the pump died as it was siphoning fuel on its own. Once you get it running is it running as if there's no problem or is it missing and bucking? Put a pressure gauge on the schrader valve on the rail and see what kind of numbers you're getting. __________________ Cammed. Blown. Nasty. BDRA #109

12-21-2011, 07:26 AM	#11
PYRT'00GT Perpetual Monthly Income Join Date: Aug 2000 Location: Displaced Posts: 350	Am I misunderstanding something? __________________ www.TheGlobalNetwork.com/muddybark[/COLOR]]TGN

12-21-2011, 04:35 PM	#13
PYRT'00GT Perpetual Monthly Income Join Date: Aug 2000 Location: Displaced Posts: 350	Okay, I'll test the coolant temp sensor first then the FP pressure. But IMO if it is a prob with the temp sensor then the FP won't put out the pressure. Maybe. Thx for all the input. I'll be back __________________ www.TheGlobalNetwork.com/muddybark[/COLOR]]TGN

12-17-2011, 04:14 PM	#2
87'hybrid Registered User Join Date: Aug 2005 Posts: 1,827	Can you hear it prime when you turn the key to the on position?

12-18-2011, 04:26 PM	#6
87'hybrid Registered User Join Date: Aug 2005 Posts: 1,827	You should hear that buzz either way.

12-21-2011, 03:59 PM	#12
87'hybrid Registered User Join Date: Aug 2005 Posts: 1,827	Some of us think it's the fuel pump, others think it's the temp sensor.

01-05-2012, 04:01 PM	#17
87'hybrid Registered User Join Date: Aug 2005 Posts: 1,827	I suggest you get the whole pump assembly, and not just the pump. I changed just the pump in my '87, and 200 miles later acted up again. Turned out to be low voltage through the old wire harness. http://www.autozone.com/autozone/par...0626_200274_0_ This should work ok. There are better pumps for a little more $$ though.

01-05-2012, 05:05 PM	#18
03RedFireGT Registered User Join Date: Jan 2004 Location: Corn Fields of Central Illinois Posts: 5,073	255lph SVT Focus pump. Not gonna cost you anymore than a stock replacement. Go through a dealer, Tousley Ford is my goto for great prices. Don't trust a VatoZone unit. Put a pressure gauge on the rail and check all your fuses to ensure it truly is your pump that is bad. __________________ Cammed. Blown. Nasty. BDRA #109

01-15-2012, 05:52 PM	#19
PYRT'00GT Perpetual Monthly Income Join Date: Aug 2000 Location: Displaced Posts: 350	Any reason I shouldn't purchase this on from an online aution site __________________ www.TheGlobalNetwork.com/muddybark[/COLOR]]TGN

01-16-2012, 04:04 PM	#20
87'hybrid Registered User Join Date: Aug 2005 Posts: 1,827	That doesn't come with the assembly or gaskets and hose clips you may need. But that is a decent pump at a good price....