i need some car help

BaYa · 04-04-2006, 08:43 PM

I have a 1991 EB Falcon S series 1 on duel fuel

my problem at the moment is that my car won't always run on petrol most of the time, some times it starts petrol on a rare occasion but most of the time it starts then dies on backfires maybe then dies, so i have to start it on straight gas. i've tried changing the fuel pump twice but it did nothing and im not shore where the relays are. thats my story and this is my first post so any suggestions would be great

mcflux · 04-04-2006, 09:18 PM

*blind stab post*

Could it be the timing/dizzy? IE set up better for gas, and uber crap on petrol?

Racecraft · 04-04-2006, 09:23 PM

the injectors could be gummed up from lack of use?
Changed the fuel filter lately?
How old is the ULP in the tank?

Scott · 04-04-2006, 09:24 PM

How long has the car been running dual fuel and how much of that has been on gas? Could be that your injectors are clagged.

BABOSS · 04-04-2006, 09:25 PM

Quote:

Originally Posted by BaYa

I have a 1991 EB Falcon S series 1 on duel fuel

my problem at the moment is that my car won't always run on petrol most of the time, some times it starts petrol on a rare occasion but most of the time it starts then dies on backfires maybe then dies, so i have to start it on straight gas. i've tried changing the fuel pump twice but it did nothing and im not shore where the relays are. thats my story and this is my first post so any suggestions would be great

possible Blocked fuel injectors, fuel filter, rusted out/dirty fuel tank, check fuel pressure.

BaYa · 04-04-2006, 10:19 PM

i run the car on gas about 3 or 4 times a week as i deliver pizza's so i use gas when i do Deliveries and on some long trips otherwise its petrol all the way but the problem i have is with the petrol not the gas. and the gas tank was man on 20/7/1993 btw. the petrol just wont always start the car so i have 2 straight start it on gas to start the car but then the fuel pump fires up later after driving the car for a while. so i have no idea and its ИИИИing me

mcflux · 04-04-2006, 10:25 PM

Quote:

Originally Posted by BaYa

im not shore where the relays are.

I just re-read your first post mate. Relays should be situated near your battery, hidden by a black plastic cover. Not sure which relay does what though, as there are about 4 of them from memory (ie horn, fuel pump, headlights, and another for summink I can't think of)

BaYa · 04-04-2006, 10:26 PM

Quote:

the injectors could be gummed up from lack of use?
Changed the fuel filter lately?
How old is the ULP in the tank?

no idea about the fuel filter have to check, im new to fixing my car but i want to learn as im a p-plater and have been driving for the past 6 months. im not affraid to get my hands dirty when i have people helping me

BaYa · 04-04-2006, 10:28 PM

Quote:

Originally Posted by Ghia5L

I just re-read your first post mate. Relays should be situated near your battery, hidden by a black plastic cover. Not sure which relay does what though, as there are about 4 of them from memory (ie horn, fuel pump, headlights, and another for summink I can't think of)

ive had a look around there befor i was think it was under the water bottle but i have no idea im just guessing

fmc351 · 05-04-2006, 12:01 AM

Quote:

Originally Posted by Ghia5L

I just re-read your first post mate. Relays should be situated near your battery, hidden by a black plastic cover. Not sure which relay does what though, as there are about 4 of them from memory (ie horn, fuel pump, headlights, and another for summink I can't think of)

That block of relays are not the EFI and pump ones.

There are 2 relays under that block. These are the EFI and Pump relays.

MPFI = Green relay (Pump) and Brown relay (EFI) Could be vice versa, but im pretty sure those colours are correct. Theyre definately Green and Brown for MPFI anyway, and definately under the main block of relays beside the battery.

CPI = Black and ???

mcflux · 05-04-2006, 01:05 PM

Quote:

Originally Posted by fmc351

That block of relays are not the EFI and pump ones.

There are 2 relays under that block. These are the EFI and Pump relays.

MPFI = Green relay (Pump) and Brown relay (EFI) Could be vice versa, but im pretty sure those colours are correct. Theyre definately Green and Brown for MPFI anyway, and definately under the main block of relays beside the battery.

CPI = Black and ???

Ahh well, my bad

:

We're getting warmer though!

fmc351 · 05-04-2006, 07:29 PM

Quote:

Originally Posted by Ghia5L

Ahh well, my bad

:

We're getting warmer though!

At least were in the engine bay, on the right side even.

Id say the relays have nothing to do with it. Its gonna be an injector, pump, filter thing.

BaYa · 06-04-2006, 12:16 AM

Quote:

Originally Posted by fmc351

That block of relays are not the EFI and pump ones.

There are 2 relays under that block. These are the EFI and Pump relays.

MPFI = Green relay (Pump) and Brown relay (EFI) Could be vice versa, but im pretty sure those colours are correct. Theyre definately Green and Brown for MPFI anyway, and definately under the main block of relays beside the battery.

CPI = Black and ???

i changed the green relay anyway and no change and then i cheackd the looms to see if there where any exposed wiring but there wernt so its either pump or som other thing related with fuel getting to the engine at start up.

fmc351 · 06-04-2006, 02:39 AM

Ive only seen the remnants of a gas system, and I pulled those remnants from my EA recently.

Theres a 'petrol starter' junction box (mine was on the firewall, left side next to MAP). Look at that to see if its got any loose connections. I have no idea what the bas&#rd does, but I assume it switches from fuel pump to gas solenoid depending on what you want to run on. (id say the pump wouldnt fire up at all if gas was selected though)

Can you hear the fuel pump kick in? Does it shut off after its starts?
The pump is supposed to start pumping with the ignition on, and will shut down in a second or so if the crank doesnt turn.

Once turning or running the pump doesnt shutoff (except when gas is selected because of that isolation switch i mentioned above id say). It could be shutting the pump down.

Get someone to start it, while you listen at the rear, see if the pump shuts off before the car dies. That will eliminate the pump curcuit anyway.

If the pump is CFI, not MPFI, it will cause a problem too.

On those relays. The Pump relay obviously powers the pump, but its feed is from the other relay. The other relay feeds the whole EFI system. If thats cactus, changing the pump relay will not eliminate the relays as a fault. Look at the brown one too.

You can actually hold them, and get someone to turn the ignition on, they will click in your hand and youll feel it. One will click first, then immediately the next. If no crank turn, they both will click off a second later.

BaYa · 07-04-2006, 12:01 PM

Thank you for all your great sugestions, i fixed the problem

after i riped half the car apart. what is was, was a little joiner which joined the cables together had burnt and this joiner was located under the dash this was all my problem was not the relay, not the pump but a little frigin joiner