Fuel pump 86 MR2

[Scott 158]

No fuel getting to enginge disconnected fuel filter tried to start car no fuel through line. Is ther anything else i should check before changing fuel pump. I checked pigtail to fuel pump while cranking i have 8.6 volts.

Any help would be appreciated.
Thanx

[Papo J]

This problem has probably been fixed but just in case. Check the AFM door and make sure it isn't stuck, the EFI fuse and relays, you can also jumper the FP and E1 pins (I think is those 2) on the diagnostic connector to activate the pump with the ignition switch so you can test it.

[IRISH13]

I just bought a 87 n/a it starts then dies starves out no fuel pressure at filter but it primes what could it be anything besides the fuel pump?

[LokiRx7]

Originally Posted by IRISH13

I just bought a 87 n/a it starts then dies starves out no fuel pressure at filter but it primes what could it be anything besides the fuel pump?

Read the post above yours.........................

And definately check your AFM.

[Racer23gt]

im just learning..dont know the abrev's..what is AFM?? and the E1 pins?? my mr2 has the same problem..it starts when i use starter fluid...but it will not stay running without it..it has been sitting for a little under a year now..so any suggestions on what may have happened.

[muffinman]

Originally Posted by Racer23gt

im just learning..dont know the abrev's..what is AFM?? and the E1 pins?? my mr2 has the same problem..it starts when i use starter fluid...but it will not stay running without it..it has been sitting for a little under a year now..so any suggestions on what may have happened.

AFM is Air Flow Meter

E1 and Fp pins are in the diagnostic port in the engine bay

after my car sat for a long time with old fuel in the tank the pump seized so maybe yours might just need replacing.


(this is the AFM)

[Racer23gt]

thanks that helped me out a lot..i have another question..if i wanted to check the fuel filter where is that located on the car? i havent checked the fuel pump yet but that will be my next stop..

[muffinman]

the fuel filter is on the firewall on the drivers side. if you look down behind the battery you will see it mounted to the firewall.

[muffinman]

read this it will help you out
MKI MR2 Write-ups

[Racer23gt]

ive been lookin for somethin like that, i cant find things that explain it that simply anywhere...what is the best way to figure out if my fuel pump is bad or good..also if i can drain the gas without removing the tank..any help would be appreciated..im trying to learn this stuff, i really want to get this car moving.

[muffinman]

Originally Posted by Racer23gt

also if i can drain the gas without removing the tank

what year is your car? 87 to 89 had a drain plug in the bottom of the tank but if yours is 85-86 you will have to syphon out the majority. once you remove the center console you will find the electrical connectors for the fuel pump and the sending unit which need to be unplugged to take out the tank. if you remove the sending unit you can syphon it from there (that's how i did it assuming yours isn't 87-89).

[Racer23gt]

its an 85 so ive figured out there's not a drain plug..ive taken out the console so far and disconnected those two wires..but i dont see a way to feed the wires down or anything ..are the wires connected to the tank? will i have to feed them out of the car while seperating the tank from the car? or possibly reach the fuel pump from under the console without even messing with the tank?also the manual says something about disconnecting brake lines and all that jaz..so im just looking for some specifics here..i need a thorough explanation to really get what i need to do..done , cause the repair manual has all this extra blah blah and fancy word play that just throws me off. thanks for the answers so far..youve been a great help.

[Racer23gt]

[muffinman]

this is probably too late but there are no brake lines to disconnect just move the parking brake cable. the wires for the fuel pump and sending unit drop out through the hole (make sure you feed them back up through before you strap in the tank). the only way to change the fuel pump is to drop the tank. disconnect all the rubber hoses at the rear and then remove the two tank straps. make sure the car is high enough and safely supported on jack stands because you will have to wrestle it out and back in.GL


if you already did it , then congratulations because nothing else will ever seem that hard again.

[YellowJacket]

Originally Posted by Racer23gt

what is the best way to figure out if my fuel pump is bad or good.

Use the fuel pump interlock bypass at the test connector. That will tell you if the pump works. I think that they are called FP and B+. You jump them together and the fuel pump comes on with the ignition.

With the ignition switch turned to 'ON', and the Fp and B+ connectors jumped you should hear fuel noise from the pressure regulator return hose. It will be quite obvious. If not check for voltage to the pump.

But if that makes things work again, then it is the interlock switch in the AFM or the relay that goes with it, and not the fuel pump.


Another MR2 Owner mentioned this trick

Originally Posted by 85SuperGZE

A quick trick I learned, if you pull the afm leave the connector in and you can physically move the flap in the afm to make the pump activate, if your afm is bad, chances are it's not bad at the wide open position, since there are diffirent levels of function where the flap is positioned.(ie. diffirent specs per bgb to check the afm operations at certain flap positions). I did this when the fuel pump wasnt within spec and had to replace it but the tank was full, so to get the gas out I undid the feed line to the fuel filter put a gas can under it and fluctuated the afm flap to make the pump "think" it needed to supply fuel. You have to have the key in the on position. It only works if the fuel pump has any life left in it, saves you from syphoning the gas out. DOING THIS IS AT YOUR OWN RISK, KEEP HEAT AND FLAME AWAY, EVEN SHOP LIGHTS, KEEP FIRE EXSTINGUISHER NEARBY AS A WATER HOSE WILL ONLY SPREAD A LIQUID GAS FIRE, I IN NO WAY TAKE RESPONSIBILTY IF SOMETHING BLOWS UP OR CATCHES FIRE. A just in case warning for anyone attempting this, not that most of you aren't smart, it's if your too smart and want to blame somebody legally.

[mr2_mk1.5]

If you have to drop the tank replace the pump wiring, drill a hole through the top of the plate and feed new power and ground wires down and attach them directly to the pump, and seal the hole with an epoxy that is gas resistant, trust me in the long run you will be thankful, I've seen 4 of them where the wire connector for the positive has failed(the connector thats epoxied to the top) and nothing is more of a pain then doing one of those pumps to have to drop the tank again in a week to fix it, also that could cause an intermittent pump problem, I've been down that road on my own personal two when I first got her, also off topic but if you have weird electrical gremlins pull the left B-pillar trim off, behind the seat where the seat belt is and look for a ring connector with two to four wires going into it cut the terminal off crimp and solder a new terminal on and sand down the mounting point to bare metal and reattach and cover with dielectric grease(silicone brake grease works great) that is one of the main grounds and causes all sorts of fun stuff to happen.

[Xenon676]

Would that keep the injectors from firing and blow the INJ1 fuse?
nevermind problem fixed