Yet another fuel pump problem!

[TwisteD90]

Everything was fine with thd D90, so I decided to lower it since sat to high. I start it and move it to the middle of my garage, start working on my suspension; I'm done; now I need to take it for a test drive. I hop in turn the key and nothing, the fuel pump would not buzz, I tried several times and nothing. So I pull all the fuses to see if I have a blown one and they are all good. I put all of them back and guess what the pump buzzed when I turned the ignition on. However, the truck will start and then after a second it dies again, started it again and died after a second. The third time the pump did not buzz. I press all the fuses back to make sure nothing is loose. I turn the key and nothing, no wait it buzzed, no wait it stopped. SO right now I'm thinking it something electrical. It could be the relay so as soon as the dealer gets the relay I'll put it in. Right now I have no clue as I have zero knowledge when it comes to electrical. Any ideas?

[DJ Menasco]

I think you're on the right track Yousef. Its probably the relay. The inconsistancy in the pump itself makes the relay highly suspect.

I have zero knowledge when it comes to electrical. Aren't you an EE? Actually, you're an E.I.T.! :grin

DJ

PS Can't you get the relay somewhere else? I was under the impression that you could pick this relay up at pretty much any shop? That way you won't have to wait for LR to recieve it and you can fire up that beast for the weekend!

[javelinadave]

Just a wag, lift the body up while the rear axle pulls away from the frame. Then try to start it. I wonder if you are pinching a wire somewhere.....Just a guess???

[TwisteD90]

I think you're on the right track Yousef. Its probably the relay. The inconsistancy in the pump itself makes the relay highly suspect.

[/B] Aren't you an EE? Actually, you're an E.I.T.! :grin

DJ

I guess I have to wait for the dealer to call me.

No thanks, I'm CE ;) And as for my E.I.T exam I bet you I got all the EE questions wrong.

[TwisteD90]

Just a wag, lift the body up while the rear axle pulls away from the frame. Then try to start it. I wonder if you are pinching a wire somewhere.....Just a guess???

Mmmm interesting. I don't think there are any wires near the axles or any suspension component. I'll give that a try anyway.

Thanks,

[DJ Menasco]

I guess I have to wait for the dealer to call me.

No thanks, I'm CE ;) And as for my E.I.T exam I bet you I got all the EE questions wrong.

:lol Its a good thing you're a CE. Man those EE guys are geeks! While I've got no room to talk working in the field of science the EE guys take the cake! :nerd

About the dealer & relay, I seem to remember Phil going through this and he found the relay local to him? Maybe he'll chime in and let us know the universal part number for that relay. After all, it’s not a bad idea to carry a spare.

Anyway, Dave does bring up a good point. I would snoop around the gas tank and the passenger side of the frame where all your fuel & electrical lines run. There could be a chance that you jostled a connection loose.

DJ

[Mike Hippert]

HEY the relay is the same as evry other 5 pin relay in your 90! Just pull one of the other ones or go to the auto parts store and ask for a relay, you must be a lucky guy or something because I just pulled apart my super electrical tape waterproof job and looked at the relay and its the same as the others just in a metal case! You can get bosch relays at Autozone if you realy want the relay to look the same. I always carry 3 extra relays just in case they are cheap at $5 each.
:grin

[TwisteD90]

It's Aliveee again :) I took the old relay to napa and i got a replacement for $10, put it in and the truck works just fine.

Thanks for the help guys.

[Mike Hippert]

WOOOOOOHOOOO! I hope it lasts longer this time:grin

[Roadsiderob]

Actually, those two little silver relays are special...in that they have 2 outputs whan switched on. They are not the same as a generic 5 pin relay that has 1 putput when switched on and one output when switched off. The end result of putting a generic 5 pin relay in place will be either 1) a check engine light for a code 44/45 (after approx. half hour of continuous driving) because the O2 sensor heaters aren't switched on while running, or 2) a dead battery because the O2 sensor heaters are switched on when the truck is parked. I hope the parts tech at NAPA looked at the schematic diagram embossed on the relay and sold you an appropriate replacement.
Cheers,
Rob Dassler

[Mike Hippert]

Hey Robert,

Not trying to start a war but on 5 pin not a 4 pin the 2 pins labeled 87 turn on when the relay is engaged. I just went out and measured everything on my 90 with my meter to make sure everything was as I said (same as you said). Look at the link, on a 4 pin relay the pin labeled not used is not even there but on a 5 pin relay the pin labeled not there is tied directly to pin 87. So as long as the relay has "5" pins it will work. What you are saying is that a normal 5 pin relay is a dual throw relay. My friend needed a Dual throw and we could not find any in the automotive style (like in the diagram) anyplace in town, that’s 5 different auto parts stores including NAPA. As far as I can see they don't make dual throw relays in that style body anyplace. We did find in every one of those stores that they had the standard 5 pin relay where there were 2 pins the ( in the diagram the one labeled not used and 87) labeled 87 and they were both switched on at the same time. So like you said the relay needs to have 2 pin 87s

http://www.d-90.com/forum/attachment.php?attachmentid=85

[TwisteD90]

Actually Rob is right. I tried to start the 90 this morning and nothing. The battery is gone :( However, I have a yellow top sitting in the garage that I'll install soon.

My relay is at the dealer and I'll pick it up tomorrow.

The funny thing is that the diagram is the same between those relays :?

[Roadsiderob]

As far as relays go, there are several configurations. Most Land Rover relays are yellow 4 pin and green 5 pin....the yellow 4 pin relays have pins marked 30(battery power in), 85 & 86(power & ground to control the relay), and 87 (switched output). The green 5 pin relays also have an 87A, which is switched to 30 when the relay is off, and open circuit when the relay is switched on...this way you can use the relay to switch circuits off as well as on. This is what I am referring to as a generic 5 pin relay. There are also specialized relays that have the same pin layout but have 2 87 terminals...such as used for the main relay and fuel pump relay. Also, some specialized relays contain other internal components such as resistors or diodes. So even though the pin arrangement and pin count may look the same, not all relays are the same internally and it is important to make sure that the replacement that you are sourcing is internally correct.
Rob Dassler

[Mike Hippert]

HMMMMMM my fuel pump relay is the one with 2 87s and I have 3 spares from differnt places that are the the same (2 pin 87s). Hey Yousef, what does it say on the bottom of the relay, sometimes they lable the pins. And Rob do you know if there is a differance in relays between the years?

[TwisteD90]

I'll pull mine off tonight and I'll post what says on the relay.

[Roadsiderob]

Mike,
The main EFI relays and fuel pump relays are the same on all 13CU, 14CU, and 14CUX fuel injection systems...all having 2 pin 87s. I think the issue here is what constitutes a 'standard' 5 pin relay. If you go to a Land Rover Dealership and ask for a 'standard' 5 pin relay, you will get a green relay with an 87 and an 87A output. They are used in various applications on the vehicles and if you put one in place of the fuel pump relay, you will have the symptoms that I described. What you get at an auto parts store if you ask for a 'standard' 5 pin relay is probably more dependent on the experience of the parts tech and what the store stocks...my point being that they are not necessarily universal and to know your application and make sure you get an appropriate replacement part.
Cheers,
Rob Dassler

[Mike Hippert]

KO so make sure you get a relay with 2 pin 87's! I looked again and mine are all 2 pin 87's they are the ones that are on the shelf at the autoparts store next to the fog lights. Still waiting on Mr. Yousef.

[TwisteD90]

Mr. Yousef had some internet problems. Hopefully he'll get you the pictures tonight ;)