Fuel pump (1 Viewer)

[LandCruiser91]

A faulty FPR typically manifests itself as hard starting when hot.
It will overpressurize the fuel rail and the check valve in the fuel pump will stick closed.

Bench tested EFI and COR. Good relays are 50-120 ohms of resistance. EFI shows 66 ohms and COR shows 26 ohms. I'll know in about an hour or so.
When the FPR on my 91 Explorer went out, it went from 75 on the interstate to idle and fuel pouring down the block

 

[jonheld]

Bench tested EFI and COR. Good relays are 50-120 ohms of resistance. EFI shows 66 ohms and COR shows 26 ohms. I'll know in about an hour or so.
When the FPR on my 91 Explorer went out, it went from 75 on the interstate to idle and fuel pouring down the block

Where are you getting these specifications from? I don't recall seeing relay coil specifications in the FSM.
Coils will fail as an open or a dead short. They will not magically change resistance.

 

[jonheld]

After checking everything, but not finding a banjo fitting to do a pressure check, I replaced the fuel pump, and she fires right up. One small problem solved, a few more small things to go. Thanks for all info. I'm sure I'll be back for more

For future reference, there is a banjo fitting on the cold start injector on the top left side of the intake where you can monitor fuel pressure. Again, the Toyota FSM gives you all the information.

 

[LandCruiser91]

For future reference, there is a banjo fitting on the cold start injector on the top left side of the intake where you can monitor fuel pressure. Again, the Toyota FSM gives you all the information.

They don't have the FSM in stock. Has to be ordered. Will probably come in Japanese so I can't friggin read it.

 

[LandCruiser91]

Where are you getting these specifications from? I don't recall seeing relay coil specifications in the FSM.
Coils will fail as an open or a dead short. They will not magically change resistance.

More of this Haynes s*** I reckon. It just amazes me that no one has ever had this issue come up and resolved it. So the resistance read the same between the old and new one on both parts. I'm gonna go pick up the COR and pop it in. Hate throwing another $50 into it, but oh well.

 

[Marco Lau]

swap in the older camry style green relay for the factory metal ones and its been working for me for the last 3 yrs. I keep a few spares just in case.

 

[LandCruiser91]

swap in the older camry style green relay for the factory metal ones and its been working for me for the last 3 yrs. I keep a few spares just in case.

Hell.. I'll try it. It's don't got me pissed now. You talking EFI or COR?

 

[ColoradoBoy]

A faulty FPR typically manifests itself as hard starting when hot.
It will overpressurize the fuel rail and the check valve in the fuel pump will stick closed.

I found this out the hard way, with @jonheld giving me help along the way. He is one of the gurus here, follow his guidance & you will improve your knowledge thru his experience and help.

Hard to start when weather and vehicle are hot- SOLVED

Been half-heartedly chasing this issue for awhile, but now I've had it! Gotta get this issue fixed. Broke out the FSM, bought a fuel pressure gauge set, and went to work. Started with pulling the cold start injector (FSM, pages FI-52-53) I cleaned it up not long ago, but figured I would make...

forum.ih8mud.com

I'll 2nd the opinion of Jon- throw the Haynes manual in the garbage & get the FSM. You can't really go wrong with information written by the people that built your rig. Keep at it- you'll get it!

 

[landtank]

Bench tested EFI and COR. Good relays are 50-120 ohms of resistance. EFI shows 66 ohms and COR shows 26 ohms. I'll know in about an hour or so.
When the FPR on my 91 Explorer went out, it went from 75 on the interstate to idle and fuel pouring down the block

Just change out the EFI relay. This is a very well know problem. I bought a beautiful 91 for my son and had to drive it home from PA. Left the the dealer and 15 minutes later pulled into a gas station and after fueling up it would crank but not start. Pulled the EFI relay and waved it around to cool it off. Plugged it back in and drove home. It’s just the way they are. My buddy keeps a spare EFI relay in the glove box.

 

[jonheld]

They don't have the FSM in stock. Has to be ordered. Will probably come in Japanese so I can't friggin read it.

FSM Scans

 

[flintknapper]

They don't have the FSM in stock. Has to be ordered. Will probably come in Japanese so I can't friggin read it.

或は

 

[LandCruiser91]

或は

Yeah.. just like that!

 

[LandCruiser91]

Just change out the EFI relay. This is a very well know problem. I bought a beautiful 91 for my son and had to drive it home from PA. Left the the dealer and 15 minutes later pulled into a gas station and after fueling up it would crank but not start. Pulled the EFI relay and waved it around to cool it off. Plugged it back in and drove home. It’s just the way they are. My buddy keeps a spare EFI relay in the glove box.

Doing that today. If it works, I'll be a happy camper.
Thanks for the help!

 

[LandCruiser91]

Doing that today. If it works, I'll be a happy camper.
Thanks for the help!

Ok..new EFI relay, new COR relay, new fuel filter...does the same thing after a few crank and runs.
I'm going to take it to a family friend who is supposed to be the man with electrical stuff. I'm so done

 

[LandCruiser91]

Ok.. as of yesterday I was at wits end. Mad because of the no start issue. Nothing was working.
Today, my brother looked it over, and found a loose coolant temp sensor. After pushing all of them in and nothing, this one clicked.
It has not failed to start yet. At least 10 times now, cool, hot, after driving and after idling. I don't know why, but so far so good. The frickin coolant temperature sensor... REALLY?!?!?

 

[ColoradoBoy]

Ok.. as of yesterday I was at wits end. Mad because of the no start issue. Nothing was working.
Today, my brother looked it over, and found a loose coolant temp sensor. After pushing all of them in and nothing, this one clicked.
It has not failed to start yet. At least 10 times now, cool, hot, after driving and after idling. I don't know why, but so far so good. The frickin coolant temperature sensor... REALLY?!?!?

Funny how sometimes the (seemingly)most trivial things make ALL the difference, huh? Been there!
Cheers!