96 park avenue fuel pump relay location

HELP PLEASE
Where is the fuel pump relay exactly on this car-I have found relays under the dash in the fuse panel and pulled all of them out and the car still runs--There is no diagram anywhere to locate this part..

Thanks in advance

Welcome Aboard!

The fuel pump relay is located in the underhood electrical center, located at the upper edge of the firewall under that long plastic cover which reads "Maxi Fuse/Relay Center." IIRC, the F/P relay is the second from the right (passenger side) of the car, although they can be moved around by simply unclipping them. The only sue method is to verify the wire colors in the relay connector. You should be looking for the relay with pink, gray, black, and dark green/white wires.

Removing the relay on a running engine shouldn't shut off the pump, since the pump circuit is also paralleled by the auxiliary oil pressure switch.

Are you trying to remove the relay to disable the engine? Installing an alarm or something?

If you're just trying to kill the pump, remove Fuse 6 (the fuel pump fuse).

Welcome Aboard!

The fuel pump relay is located in the underhood electrical center, located at the upper edge of the firewall under that long plastic cover which reads "Maxi Fuse/Relay Center." IIRC, the F/P relay is the second from the right (passenger side) of the car, although they can be moved around by simply unclipping them. The only sue method is to verify the wire colors in the relay connector. You should be looking for the relay with pink, gray, black, and dark green/white wires.

Removing the relay on a running engine shouldn't shut off the pump, since the pump circuit is also paralleled by the auxiliary oil pressure switch.

Are you trying to remove the relay to disable the engine? Installing an alarm or something?

If you're just trying to kill the pump, remove Fuse 6 (the fuel pump fuse).

I am trying to fix a stalling issue and wanted to locate the relay so I could replace it--I thought If I pulled the correct relay and the car did not start that would be the one I wanted to replace.Adnanced auto sold me a relay but it does not look like tho ones under the hood so I will take it back along with the one you told me about and have them try again...Thanks for the quick response..I will let you know how I do on getting this issue resolved

I am trying to fix a stalling issue and wanted to locate the relay so I could replace it--I thought If I pulled the correct relay and the car did not start that would be the one I wanted to replace.Adnanced auto sold me a relay but it does not look like tho ones under the hood so I will take it back along with the one you told me about and have them try again...Thanks for the quick response..I will let you know how I do on getting this issue resolved
That idea did not work at all.The color combinations you gave me do not match any relay color codes.The relay I was sold matched the relays under the dash but none of them seem to keep the car from starting if the correct pump relay is removed. The local library did not have a shop service manual to consult-I may have to travel to another library to find a manual for this car unless you have any other ideas of why this car keeps dieing after be driven about 10 miles--It will start up as I am coasting to a stop in neutral.
I have replaced the Crank position sensor and may replace the cam sensor next.

More than likely you had the right relay! :iceslolan The fuel pump relay is located under the dash, passenger side fuse/relay center and it looks like this!
Click Here (http://info.rockauto.com/SMP/SMPDetail2.html?RY232.jpg)
http://info.rockauto.com/SMP/SMPDetail2.html?RY232.jpg

Thanks for the reply. I pulled out all relays in that fuse panel and the car will start and run--Why should the car stay running without the pump relay in the circuit-Maybe I need to disconnect the oil pressure switch also if that is in the same circuit to help me know for sure exactly the relay that need's to be replaced There ar 3 different possibilities in the fuse panel but can not find anybody to tell me exactly the one that it is-I hate to spend $130 for a shop manual at this time since I am currently on job lay off-I may have to drive to Indianapolis to the library to photocopy some pages from a manual if I can locate one or if someone here could post a pic of the fuse panel with the relay indicated.

The pic below is the relay/fuse panel under the dash. It is specific to the Buick & LeSabre in the mid 90's, however could be a little different on the 96.

BTW, I do not understand why you are so focused on the fuel pump relay as being your problem! If you think you have a fuel issue, you need to check fuel pressure when it stalls, or will not start. In addition, this problem is more likley the ICM, or CKPS. That is why we always suggest checking fuel pressure and spark when it stalls!

Oh, I almost forgot to answer your question (that was previously answered) about why the fuel pump will continue to run with the relay disconnected. The fuel pump control circuit, includes an engine oil pressure switch with a separate set of normally open contacts. The switch closes @ 4 psi of oil pressure and provides a second battery feed path to the fuel pump. If the relay fails or, (is removed as in your case) the pump will continue to run, using the feed supplied by the closed oil pressure switch!

In conclusion, even if your relay fails, the fuel pump will continue to run as long as the engine has oil pressure, so therefore, you can eliminate the relay as being the cause of your stalling! Go back to the fire and fuel pressure check when it stalls and let us know what you find!


http://files.automotiveforums.com/gallery/watermark.php?file=/503/297374buickrelaycenter-med.jpg (http://www.automotiveforums.com/vbulletin/%5Bimg%5Dhttp://files.automotiveforums.com/gallery/watermark.php?file=/503/297374buickrelaycenter-med.jpg%5B/img%5D)

Thanks for the reply
I installed a fuel pressure tester and ran the engine untill it died.the fuel presure dropped slowly from 42 p.s.i. to 0 then the car died after about 15 to 20 seconds; so my thinking is now the fuel pump or connector on top of the fuel tank. I pulled the vacuum hose off the pressure regulator on the fuel rail and the pressure increases to 52 p.s.i. at idle so I do not think that is the culprit.What are your thoughts on this? I was also wondering what color wires ran to the fuel pump under the back seat? I want to connect a test light to the power feed wire for the pump and see if it goes out or not when the car dies. Would this be an indication the fuel pump is getting hot and shutting down if the test light stays on when the car dies?
Also I have alreadt replaced the crank sensor and oil pressure switch.
Should I also consider the cam sensor? I am also considering taking the car to a garage and have them put it on a diagnostic machine.

Thanks to HotZ for that correction. I was under the impression the FP relay was in the UEC. Sorry if I mislead you. I must've been thinking of a different W body instead of an H.

I installed a fuel pressure tester and ran the engine untill it died.the fuel presure dropped slowly from 42 p.s.i. to 0 then the car died after about 15 to 20 seconds I have a few questions for you here. How long did the engine run before it stalled? Do you have plenty of fuel in the tank? (1/2 tank or above) When was the last time the fuel filter was changed? (A clogged fuel filter is one of the leading causes of fuel pump failure)!
I pulled the vacuum hose off the pressure regulator on the fuel rail and the pressure increases to 52 p.s.i. at idle so I do not think that is the culprit. What are your thoughts on this? I agree, the FPR appears to be OK.
I was also wondering what color wires ran to the fuel pump under the back seat? I want to connect a test light to the power feed wire for the pump and see if it goes out or not when the car dies. Would this be an indication the fuel pump is getting hot and shutting down if the test light stays on when the car dies? You have a GRY (gray) wire from both the oil sending unit circuit and from the fuel pump relay, that join somewhere between the relay and fuel pump. If you think the connector or terminal at the tank could be the problem, it would be of no benefit to put a test light in the wire before that connection. (I will email you a schematic on the fuel pump circuit).
Should I also consider the cam sensor? I am also considering taking the car to a garage and have them put it on a diagnostic machine. The cam sensor has nothing to do with the fuel pump operation. It is only used for the timing of the injector firing! In fact, you can disconnect the cam sensor, and the engine would continue to run, however, it would have a slight hesitation. A scanner will not tell you anything about the fuel pressure or the fuel pump wiring other than that the fuel pump relay was toggled on/off. In summary, if you have consistent power feed to the fuel pump with no restriction at the fuel filter and the regulator is doing its thing, it is time for a new fuel pump. You have some very good thoughts, however, don’t try to over diagnose this. The fuel system is not that complicated.
Good Luck! :grinyes:

The car will run at idle for 1 or 2 hours before stalling or driving it down the road about 20 miles.I replaced the fuel filter last week-seemed plugged up somewhat-you could not blow air through it using my lip air.So I agree with you-I think it may be time for a new fuel pump--But why would they restart after shifting to neutral?Is there an element inside that gets hot and can reset? The car was taken for a joy ride by some teenagers last fall and looked as if oil of some sort had been spilled on the fender as if it were put into the tank.Injector cleaner has been run through allready. I may want to drop the tank and take it and get it cleaned out if I put a new pump in it. I would appreciate the scematic-I know how to read them.I was a certified auto mechanic in electrical,a.c. and brakes back in 1983 so I have been out of the field for awhile since all the new computer controls have come out on the cars. I was reading on one forum that they had problems with the fuel pump connectors on this model of car.I will try to order one of these if I decide to drop the tank.

UPDATE: I found the fuel pump relay as you showed in the diagram above;;I started the car and pulled the fuel pump relay and the car died--What is that telling me.Does that mean I have a fault in a cicuit somwhere such as a disconnected wire or sensor.I have allready replaced the oil pressure switch.Is it a bad new part? I thought the oil pressure switch would keep the car running if the pump relay was not in the circuit?What am I missing here?The oil pressure gauge in the dash shows good oil pressure.

Does your car have the 3.8 non-supercharged (VIN K) engine?

I was going to post a wiring diagram for you but Photobucket.com is down right now. It appears the Park Ave fuel pump does not have power coming from the oil pressure sender. So removing the relay will cut power to the pump. Before dropping the tank I would try swapping the horn & fuel pump relays. I would also check the driver's side ground bus for corrosion.

Where is that ground located?

http://www.bonnevilleclub.com/forum/kb.php?mode=article&k=102
Here's an article with some pictures of the ground bus on a Bonneville.
Hopefully its in the same location on the Park Ave. It's the connector where all the black wires meet.

Here's the wiring diagram for VIN K.

http://i197.photobucket.com/albums/aa182/MikeTu/Wiring%20Diagrams/PAFuelPump.jpg

Update:: I got the car to die with the test light connected to the gray wire under the seat.The car died then the test light went out about 15 seconds later. What does that tell me?

The PCM controls when the fuel pump gets power. When the key is turned to the run position the PCM will energize the fuel pump relay for 2-3 seconds. The relay is also energized while cranking & of course after the engine starts. I would expect it to cut power after the engine stalls.

Update: I found the grounds like the picture shows-Connections looked good but cleaned the ground strip and re-installed, Car still dies.

What made you think the problem was with the fuel pump?

I sure am leaning towards dropping the tank down but what really confuses me is why would the pump quit and then restart? I will wait until tomorrow to see if any one has any other ideas.

answer to Mickey#1 questions.It is not supercharged-not the ultra model.
I did try another relay but still no help.What would happen if I ran A hot at all time wire to the gray wire going to the pump.Would that backfeed and burn out a computer or other expensive item?

Sorry about my previous post - I forgot you confirmed the fuel pressure problem with a gauge.

You checked the grounds & confirmed with the test light that you have power going to the pump when it stalls. It does sound like it's time to drop the tank.

It appears the Park Ave fuel pump does not have power coming from the oil pressure sender
Good catch Mickey#1! It does appear that the VIN K may not use the alternate feed from the oil pressure-sending unit. Sent another email along with a diagram for both VIN K & VIN 1. The VIN 1 has a fuel pump control module, and that looks like the only difference in the 96 PA VIN K & 1.

I was wandering if something is telling the pcm to sut down the fuel pump..but has that allready been rulled out since I have power on the gray wire untill after the pump shuts down. Has anybody ever seen a pump shutdown and then restart like this one does?
One other note: I did look under the car and found a loose fuel line-Probably a loose return line.Are these hard to repair?I have never worked with plastic lines before. It does not appear to have gas thrown out around the line yet but I will have to fix it.Looks like maybe gas has been thrown on the under floor side on the other side of the car under the fill tube.I am going to drop the tank today and check the fuel connectors and the electrical connectors on top of the tank at least and probably go ahead with a new pump at this point and a new sock-The fuel looked odd when I changed the filter.
This car was involved in a collission and had body damage on the right side near the fuel tank a couple of years ago and I am thinking that may be why I have a loose fuel line or a sloppy body shop repair. I will let you guys know what I find. I really appreciate the help here.I hope my questions have helpped jogged your brains and helped you fix some of your car woes.

Thanks to all who responded,
I decided to drop the tank today and take a look see at the harness at the top of the sending unit-It looked fine and since I could not find a connector harness locally I went ahead and replaced the fuel pump and sock..
I have driven the car 34 miles today and no stalling! I will not jump for joy untill I take a little further trip tomorrow.I just did not think a pump would shut down like this and then imediately restart.

HotZ - That's the 1st pre-2000 3.8 I've seen that didn't have it.

ka9mgd - Glad you got it going.

Update: I am considering the car fixed-I drove it 52 miles today and no stalling issues

Congratulations! Let this thread be a model for others with similar fuel pump malfunctions! Your diagnosis methods were indeed intriguing and should prove beneficial to others. Thanks again for the feedback and we hope you have many more happy trouble free miles ahead! :grinyes: