EFI buick will not run after running out of fuel

[Petros]

Hi all,

since there are so many knowlagable people here I though I would run this past you all to see if you have any ideas.

We have a "geezer car", a 1998 Buick LeSaber with the v6 that my parents gave us. I do not particularly care for the car but my wife likes driving it and it has not given us any trouble over the last 40,000 miles that we have owned it (it has a total of about 126K on it).

After my wife went kayaking with some friends, and stopping for dinner and a Margarita, my wife had ran it out of fuel. Fortunately she managed to coast to a rest stop. she calls me at about nine pm last night and needs me to bring her some gasoline. I bring and put in about 1.2 gallons of gasoline, and it car will not start. It cranks and cranks, and sputters. sounds like it almost starts, even mangages to rev up to about 1000 rpms and dies. I eventually spray some starter fluid in it (before the battery gives out, the darn thing has no way to turn off the head lights!!), and it manages to come up to a idle, but everytime I hit the throttle it wants to die. I find that if I pump the pedal at a very narrow range of its travel the engine will jump up in RPM, but I have to keep pumping it or it just drops back to idle. It feels like the EFI only sees a short band to accelerate, the rest of the throttle travel is unresponsive. After about 10 min of keeping it running this way it appears to settle down and behave normally. We drive it to a gas station and fill it up.

And the whole thing starts over again but this time it is worse, it will not start, sometimes no sputters at all. I have to jump it with my tercel to keep the batter charged. We get it started finally and appears normal. We are ten miles from home, and I am following. It gets up to about 55 mph and apares normal for about 2 miles, and than goes back into its stall mode and my wife can only keep it going by pumping the throttle. It eventually dies altogether and we finally abandon at midnight it by pushing it into an unused driveway. It was putting out a lot of black smoke during this last attempt to keep it running. It put out no check engine light during the whole episode.

My thought is either we some how trashed fuel pump, or maybe it is just a plugged up fuel filter. any other ideas? We have AAA and we will bring it home this afternoon. Though frankly I just as soon have it towed to a wrecking yard.

[dlb]

haha, yes the classic buick lesabre is no fave of mine either. fuel pump, fuel filter, or air in the fuel line are my guesses. the pump could have been killed if it was marginal and was then run out of gas, and the filter could have been clogged if it was marginal and there was crud in the bottom of the tank that all got stuck in the filter at once. air in the line seems least likely since a good pump should just push it all out. i would replace the filter first, and if that didn't work i would disconnect the fuel hose, put it in a bucket, and try starting the car to see how much fuel the pump is putting out. should be clear then if the pump is ok and if you need to look into other systems.

[4wdchico]

Your fuel pump is probably history. Put a new fuel filter in it. If still not running right, likely, check the fuel pressure. Make sure that the fuel pressure rises when you goose the throttle. The fuel pressure reg reduces the F press when engine vac is high so the F press should rise when you goose the throttle. If the FP does not rise, or falls, when goosed hard off of idle your pump is failing or the wiring to it has excessive voltage drop. Being that the car was run out of gas and then the problem occurred, the probability that the circuit to the FP is the problem is slim.

[keith]

There are two things I would do first. The first is to disconnect the QD at the fuel rail and point the hose into a bucket or jar of some kind. A glass jar or bottle would be the best. Turn the key to the run position for a few seconds until you get a steady fuel flow. Then reconnect the fuel line QD and turn the key to the run position for three seconds, then off and repeat five times. This should purge the fuel system. Then start the engine and it should run normal.

If that doesn't work, the fuel pump was probably damaged. It is kept cool by fuel flowing through the pump. It is a myth that it has to be emerged in fuel to keep from overheating, but if it runs too long with no fuel flowing through it, it can be damaged.

[Petros]

thanks guys, all good thoughts. it seems likely it is fuel related since about the only thing that will not set off a check engine light is fuel starvation. It very much seems like air in the lines, but was GM so stupid as to design a system that will not self purge when it was run out? Looks that way.

It was not really run without fuel, usually what happens as soon as you run the tank dry the fuel pressure drops and the engine shuts off with a second or two. Which is exactly what happened here. there was no attempt to restart until there was fuel put in the tank. Though that does not mean the pump was not damaged, but there was very little time where it did not get fuel. It also seems an obvious fail-safe to put some kind of system to keep the pump off it there is no fuel to pump, but who knows what thoughts run though the minds of the engineers at GM. Unless it was revised out of the system by the production engineering department to save .03 on each car.

I will give the system purge test tonight, and tray a new fuel filter tomorrow after that.

[4wdchico]

First, the fuel pump will not pump fuel for more than a couple of seconds max when the key is turned to on w/o starting the car. That is to get the fuel rail pressurized in anticipation of the engine being started. I would not bother checking for fuel flow on an EFI car as flow is not what really matters. What really matters is the fuel pressure and how the fuel system responds to differences in engine load by maintaining the appropriate fuel pressure.

Once you start the car the fuel pump will shut off as soon as the crank sensor stops reporting engine revolutions to the PCM. That is your safety for the car's occupants and the fuel pump right there.

The fuel system will self purge up to the fuel rail by forcing air and fuel thru the FPR and back to the fuel tank. A few cycles of turning the key to on and then off w/o starting the engine will accomplish this providing your fuel sock, fuel pump and fuel filter are flowing fuel at a high enough pressure to return fuel and air to the fuel tank thru the FPR as the system was designed to do.

There are two other possibilities, providing that you actually have a fuel problem:

First, the fuel sock that strains the course particles out of the fuel before they enter the pump may be clogged. This can happen when the fuel level is run way down. But the fuel pressure test that I described earlier will rule this out if the fuel pressure rises solidly when the engine is goosed off of idle.

The second possibility is that the diaphragm in the FPR has failed. The putting out black smoke comment really supports this possibility. Luckily, the test is fairly simple for this: cycle the key to on and off a few times, without cranking the starter, to get the fuel rail pressurized. Then pull off the vac line where it attaches to the FPR, if fuel runs out your FPR diaphragm is blown. A car with a blown FPR will run really rich.

Petros, the following is not a criticism aimed at you, just a suggestion for anyone who might read this post and then experience a similar suspected fuel sock or pump problem: Don't fill the tank, just put a few gallons in, as you may be needing to empty the tank & then pull it so that you can R&R the fuel pump assembly soon.

[Petros]

thanks for the great info 4wdChico. Remember that after I got the car started, after some trouble, with only 1.2 gallons in it, it ran totally normally for 2 miles, even up to 60 mph on the freeway (I had driven it around the rest stop for about 5 min before going on the freeway). So it appeared what ever the problem was with air in the system, it had cleared and was running normally. No hint of a problem after that. It was out of fuel and needed to be refilled.

The big problem came after the fill up. There was much trouble getting started, and than once it did start, it appears normal again (I drove it around the gas station parking lot, and than on to a local hwy), and ran up to about 50 mph for about a mile, again normally. And than the sputtering and cutting out started again.

So my guess at this point is that their is either air still trapped in the system (I learned on a GM forum that Buicks are notorious for this problem btw), or the fuel filter, or possibly now a marginal fuel pump is putting out less than full fuel pressure. The behavior appears to be the same same for partially fail fuel pumps, that still pump fuel, but put out less than required pressure. some cars start acting this way without running out of fuel, and it turns out to be a marginal fuel pump. Of course a plugged filter or screen can cause this, and perhaps air trapped in the fuel system.

I do not know why this problem is unique to Buicks (if it really is), because the same fuel system is used in most of the GM cars and trucks.

[irowiki]

Petros, for the headlights, you can pull the headlight switch out one notch and the parking lights should come on without the headlights, if it works anything like my 2003 Regal!

I have ran my Regal out of gas once and never had any issues, perhaps I got lucky or they fixed it by then!

I would not give up on your Buick so easily, I bought mine at 88k, has 125k now, and has been rock solid except for replacing some sort of ignition wire bundle in the steering column when I first bought it!

[keith]

You may not need to drop the tank to remove the fuel pump and sending unit assembly. Most cars, not all, but most have an access cover in the trunk so that you can get to the assembly without dropping the tank. It is worth looking for.

As for saving $.03, yes GM will do that. The original OHC 4 cylinder used in the 90-93 Buick Skylarks, which was a 2 valve derivative of the quad 4 engine, had issues about the heads cracking due to insufficient aluminum around the head bolt bosses. GM only allowed the extra $.03 worth of aluminum to be added to the new production heads so that they would make it past the warrantee period. Then they wanted us to cast heads without the extra aluminum for warrantee replacement heads as they were good for about 20k miles and they would make it until the warrantee expired. We told them it would cost more than $.03 per head to modify the molds so they dropped that idea.

I might add that this was the era that if I recall right, the CEO of GM was Ed Lopez, who came up through the GM ranks in accounting and purchasing. His sole focus was on getting parts at the lowest possible price, quality did not matter. In 93, Volkswagen stole him from GM to be their CEO. The rest is history.

Correction, Lopez was not the CEO, but worked directly under Jack Smith, who was the CEO. Jack Smith was responsible for reducing costs at GM in order to return it to profitability during the recession that started in 87. Lopez was in charge of purchasing. I guess memory does not always serve me well.

VW had to fire Lopez shortly after as it was discovered that he had stolen many GM documents and took them with him to VW. VW could have lost billions in a lawsuit to GM if they hadn't fired him.

[Petros]

I installed the new fuel filter (under the car in front the passenger side rear tire), cycle the fuel pump on and off several times. I can hear it running as it is supposed to, pressed on the pressure port valve to release any air caught in the fuel rail (none found, only fuel). I pulled the vac line off the regulator as 4wdChico suggested, vac line was dry of fuel, as it should be.

Battery was too low to crank, so I put a charger on it (we had it towed home last night). I went and got my EFI pressure gauge and installed it on the test port, cycled the fuel pump by turning the key on and off several times. It showed 10 psi. Per the service manual it is supposed to show 48 to 55 psi, and drop after it starts 3 psi. I let the battery charge longer, did the test again with no change. I cranked the engine to see if just might start...no such luck. fuel pressure remained at 10 psi.

So it appears the fuel pump was damaged. According to the service manual the fuel tank does have to be dropped to replace the pump. It does not look like too bad of a job (some GM models, like the Corvette, you have remove the rear axle assembly to drop the tank). We just put in $60 worth gasoline, 20 gallons, that now I have to drain out into clean containers!!! That will take as long as dropping the tank.

New fuel pumps from Rockauto about about $50 to $100, depending on brand (interestingly they have a Denso fuel pump for it, at $100. I have noticed that the Japanese EFI car fuel pumps typically last 300k+ miles, worth the extra cost? will a buick last 300k miles?).

This buick has been remarkably reliable compared to other GM products I have had in the past, I do not care for it because it makes me feel like my 83 year old dad when I drive it (they gave it to use when they bought a new car), it is a "Geezer car". I just do not like large, soft riding cars that you can hardly feel the road or anything else that is going on when you drive it. You can not even tell the engine is running unless you look at the tach or sometimes you hit the starter again. I like smaller, sporty and more fun to drive cars that send some feedback to the driver reminding you you are driving down the road!

[irowiki]

My research showed a properly cared for Buick will last 200-250k+

I may not get to put that to the test as we'll need a bigger car as the family grows

I actually like my "old people's car", it gets fantastic MPG for being a V6 (30 highway), and is smooth and quiet while driving. Probably the best car I've owned!

On the flip side, the Tercel lets me connect with the road better :p

[Petros]

for anyone that has the same problem in a EFI car, there is the test procedure if it will not start, or if fuel pump is suspected.

1. cycle the key to on, than off, several times, without cranking or starting it. Between each cycle the you should be able to hear the fuel pump run for approx 3 seconds. If you hear the fuel pump cycling, the relay, fuse and wiring are all good. If not than an electrical check should be done to rule out the fuel pump relay and the fuel pump fuse. Mine was cycling.

2. Install a pressure gauge on the fuel rail at the port provided in most EFI systems, the older systems you have to temp splice a "Tee" into the line for the gauge. I bought my pressure gauge kit from Harbor Freight several years ago, it was on sale for $9.95 (normal price is about $19.95). Not a high quality set but for occasional use it is perfect, it comes with various hoses and adapters for different types of systems. Napa, Autozone, O'Reiley, etc. all sell something similar for a little more money. with the gauge installed you cycle on the key to "run", without starting it. On the Buick the pressure should read between 48 and 55 psi. I was showing 10 PSI, an indicator that the pump was not putting out enough pressure. But all is not lost yet.

3. You next need to make sure it is not the pressure regulator causing the low pressure. The manual says to "pinch the return fuel line", but they are plastic now, not rubber. So I pulled the return line off (GM uses that handly "quick connect" fittings, unfortunately as they age they get brittle and can break, they work good when still good), and clamped on a short length of hose with a bolt for a plug in the other end (also with a hose clamp on it good and tight, it might have to hold over 50 psi!). If the pressure regulator is bad, it should allow the pressure to go well above the maxiumum 55 psi. In my case I could only get about 12 psi out of it. So, looks like the fuel pump is not putting out enough pressure. It was delivering fuel, the reason for the fitful starts, but not enough to run properly. It was acting like a fuel starvation.

To replace the pump you have to drop the fuel tank. I did it today at picknpull (since there was a half price sale), to see how much work. The Buick has no drain plug in the fuel tank, so that will be fun getting 20 gallons of gasoline out of it. but the tank drops clear by just removing two straps and the filler hose and clamp (a rubber flex hose). when it falls out you can easily relase the 3 "quick connect" fuel or vapor lines, and the two electrical connectors. The real trouble might be with the exhaust pipe, which has to be lowered. At pick n pull it had the cat cut out and pushing the pipe aside was no problem. I do not know how much work it will be with the exhaust system all in place.

The fuel pump is integral to the sender, you can either buy a whole new assembly (about $130 from rockauto), or you can just get the motor kit anywhere from about $35 to $100, depending on brand. With the half price sale, and the $9 extended warranty (one year) on the used fuel pump, it was not a bad deal. But the regular price on the Picknpull fuel pump is a questionable purchase since you can get a new one for about the same, with the one year warranty. In my case, it was handly, and they had the correct complete assembly, so it would save some time. I expect to get it in this weekend.

[Jooseppi Luna]

My research showed a properly cared for Buick will last 200-250k+

I may not get to put that to the test as we'll need a bigger car as the family grows

I actually like my "old people's car", it gets fantastic MPG for being a V6 (30 highway), and is smooth and quiet while driving. Probably the best car I've owned!

On the flip side, the Tercel lets me connect with the road better :p

That's morealess how I feel about my Century -- the car is just incredibly relaxing; so quiet, so comfortable. It's the car I take if I'm stressed about anything .

[scrapz253]

yup. vapor locked the pump. I'm always on my wife about not letting our 05 lacrosse go below an 8th tank.

[Petros]

a new fuel pump solved the problem. it seems entirely irresponsible that a car company would have a fuel pump that dies if you accidentally run it out of fuel (like that never happens). I have run EFI cars out of fuel made by Volvo, Mazda, Toyota and Nissan with no issues, put in some fuel and off we went. One would think Detroit could figure this one out, another reason I will not buy cars made in the USA, they are either incompetent or crooks (or more likely both).