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1999 Deville base
95 Eldorado, 99 Deville, 05 CTS
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194 Posts
Discussion Starter #1
I was coming home last Wednesday from a 180 round trip to the Drs, when about 30 miles still from home, after I went thru the last light, and just got up to speed on the last leg home, the engine just laid down and died. Several months ago, on way home from work , when almost back and on the slow back roads, it would start starving for fuel so bad that I wondered if I was gonna make it. Next morning it be ok, until I got almost home again m same roads. So, I bought a fuel filter. Well, that musta scared it, because it straightened right out and I could run it as hard as I wanted, full throttle or whatever. It was perfect for several months until it just quit with no warning. I changed the filter, but still wont start. No codes. I bought a cheap tow strap and had it towed home with my good old 95 Eldorado (250k miles)m that I gave to my lady friends son. It's been too cold and rainy for me to ck the fuel pressure. Could it be anything else but a weak pump on an 05 CTS? I can hear the pump run and shut off, but it sounds kinda faint and weak to me. Also, the starter runs on for a couple secs after key is released. Anybody? Thanks guys!
 

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1999 Deville base
95 Eldorado, 99 Deville, 05 CTS
Joined
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194 Posts
Discussion Starter #2
Ok, I put the pressure tester on and it went to 15. Then 10 lbs. But it doesnt fluctuate. I hear the pump running and shutting off, but the gauge doesnt move. It's on tight, no leaks. Something doesnt seem rite? ? Like maybe something happened in the tank lines? I'm gonna see if I can take the gauge off the end n see if it pumps any fuel. The pump sounds like it should be showing more movement on the gauge. Any ideas, anyone?
 

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1999 Deville base
95 Eldorado, 99 Deville, 05 CTS
Joined
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194 Posts
Discussion Starter #3
I took the gauge off and cycled the key, the pump runs, sounds like it builds pressure and shuts off, takes about 2 seconds, but no fuel comes out of the gauge hose at all. Theres gas in it, and it's open, because I can blow in it and hear gurgle sounds, like in the fuel rail. Past the Schrader valve, and I got a mouthful when I stopped blowing in it. Anyone know what's going on here? Thanks for any replies.
 

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Registered
2007 CTS 3.6 >129k miles
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497 Posts
This sounds like one of those hard-to-diagnose issues! After reading these descriptions it seems as if the car is getting fuel, but whether the pressure is sufficient is not known. However, I would suspect an electrical issue with the ignition system or the ECM. Perhaps others who have more experience with this issue can chime in?

Also, your first post mentions that the car will continue to crank after you release the key. This is normal GM design - just hit the key and release, and the car will crank as necessary to start. However if it does not start within a few secs it will give up and you have to try again.
 

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Registered
2007 CTS 2.7L
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518 Posts
I believe the fuel pressure should be 40-50 PSI and hold for a long period of time. The pump will turn on when the key is turned on, and then turn off until the car is started. During that time, the pump "primes" and gets the system to high pressure. If you are cranking and the pressure does not get anywhere near there, then it is NOT getting fuel.
 

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1999 Deville base
95 Eldorado, 99 Deville, 05 CTS
Joined
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194 Posts
Discussion Starter #6
No, its definitely not getting fuel. I dont understand why I can hear the pump run, strain a little, like its building pressure, then shut off, but no fuel pressure at rail? You know sounds normal..but maybe its weak and not building enough pressure to get past the regulator? Which is on the pump-in the tank! I just dont want to buy a new pump, put it in, and it be something else..what, Idk. Can anyone think of anything else it could be, before I buy a new pump?
 

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Registered
2007 CTS 2.7L
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518 Posts
See what I posted earlier. That is normal to start briefly then shut off when you just turn the key to ON position. That primes the pump and pressure in anticipation of starting. It will ONLY run constantly when the car is started and running. This applies to all cars. The pump does not need to run constantly while the engine is not running because no fuel is being used and no loss of pressure. When the car is running it needs to run constantly because fuel is being used and the pump needs to maintain pressure.

The pump could still be bad and not deliver the proper pressure, but the BEHAVIOR you are hearing is normal.
 

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1999 Deville base
95 Eldorado, 99 Deville, 05 CTS
Joined
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194 Posts
Discussion Starter #8
Well. that's what I mean, Greenmachineiijh, I can hear the pump prime, so there should be pressure at the fuel rail, but I've got the fuel rail wide open and dont get a drop, either after prime, or while cranking. There is gas in the tank, albeit, low, but not on empty.
 

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Registered
2007 CTS 2.7L
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518 Posts
you could disconnect the fuel filter outlet side, crank the car and see if gas comes out there. should be quite a bit when just letting the pump prime.
 

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1999 Deville base
95 Eldorado, 99 Deville, 05 CTS
Joined
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194 Posts
Discussion Starter #10
I thought about that, but isnt that the same as having an open line at the Schrader valve, on the fuel rail? I already put a new filter on. I went ahead and ordered a pump. Found a " The 1 FP ", from US Stock, for 40$. They brag pretty good about it in their nice write up. Supps to have better tubing and other stuff.
 

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Registered
2007 CTS 2.7L
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518 Posts
If there is a kink in the line along that longer fuel path, you might find it. It is doubtful, But just another alternative.

Just grasping for straws at this point. But I think the pump is just having issues, as you are definitely leaning toward.

Report back if that fixed it for you. Pumps going out are not common that I am seeing. At lease right now.
 

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1999 Deville base
95 Eldorado, 99 Deville, 05 CTS
Joined
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194 Posts
Discussion Starter #12
Well, it does have 150k miles on it. I dnt know the average life for in-tank modular fuel pumps, but I dnt know what else it could be. Fuses all good. No codes, which surprises me. I will post what happens after I get to the pump. I'm gonna cut it out from under the back seat.
 

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1999 Deville base
95 Eldorado, 99 Deville, 05 CTS
Joined
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194 Posts
Discussion Starter #13
Update, I cut bout a 9 inch wide hole, directly behind fuse box, underneath drivers side passenger seat. Marked out 3 lines, used a small cutting wheel to cut most of the way thru, then easily finished with a light hammer n screwdriver, then bent the "flap" back. Disconnected both lines and cycled pump with key, no fuel, sometimes a little dribble. Pump sounds slow n weak. Not as fast and "loud", like it should be. I guess it just had enough. New one is almost here, according to tracking. Shoulda been here today, hope tomorrow if mail doesnt mess up. Happens a lot around here. Package will come from clear across the country, almost here, then get sent back up North 2 states, to hang around awhile, then decide to come on down! Anyway, I ddnt want to take the old one out, till the new one got here.
 

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Registered
2007 CTS 2.7L
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518 Posts
Good idea. Glad you are ahead of the game and got the hard part of cutting out of the way already. Bummer the pump went out. Not real common at all that I find on these forums.

When you pull the old one out, double check there is no water, rust, junk in the tank. MAYBE something got in there and clogged the little filter sock at the intake side. OR the sock came apart/folded.
 

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Registered
2007 CTS
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4 Posts
Had a similar issue with an 87 Mustang. The in tank hose that connects the pump to the outlet pipe that connects outside the tank broke. Pump was pumping, just back into the tank. New hose and clamps fixed it. Hope yours is easy. The fuel pressure on that model was 35-40.
 

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1999 Deville base
95 Eldorado, 99 Deville, 05 CTS
Joined
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194 Posts
Discussion Starter #16
Hey Herdsman, it was the same as you said, but different! After waiting almost 3 weeks for the stupid pump, it was the wrong one! They sent me an Airtex, with a new plug style and the crimp connectors to go with! When I took out the old pump, it had a piece that gad come detached, that another line connected to, that went over to the drivers side of the tank. It's a saddle tank, driveshaft tunnel, thru the middle. Well, I snapped the piece back on, but it came off again while inserting pump into tank, so formed a piece of baling wire around it, put it back in, and it pumped right up to 55 lbs! I wasn't about to cut n splice a different style plug on the wiring harness! Man, I'm glad it's fixed! I missed my little white car! Now I need to put some control arms on it, the insides if all my tires are worn slick, and drivers side sounds like it's gonna fall apart! Thanks for all the help everyone! Merry Christmas!
 
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