fuel pump help (1 Viewer)

[sailor95]

Hi all, been having issues with my hundy. Car started and i started backing up and it died and would not restart. Now a week later ive put in a new fuel pump and now it still wont start. I do not hear the pump turn on and no fuel coming from out end of filter. Does anyone have a picture of the fuel reset button under the dash, for the life of me cant find it, not sure if that would help but i wanna give it a try. Also how would i test my pump and relay for voltage to make sure its getting power because im not even sure which in the fuse box is the correct relay. Would a clogged filter cause the pump not to turn on? Please help. at wits end with this

 

[morganism]

Does that model have a roll over fuel cutoff switch ? Check reverse actuator switch too, it may have failed when in reverse, and truck thinks it is still in gear. Think that is actually cable actuated in the 100?

 

[sailor95]

Yea I think so but I'm not 100 percent on what it looks like or where it is/what position it needs to be in. There was a small hill I was backing up to get on road when it happened. This happened last year and I didn't replace pump just beat on it and it worked.

 

[outdoorsman]

It sure sound like a fuel pump to me.

If it went out and a year ago and you beat on it and it worked again seems like you narrowed down then. It is just like beating on a old starter with a hammer to get it to start but it is a short term fix.

You can check the relay and fuse first.

The fuel pump change out only takes about an hour.

You just pull the driver side back seat out. Lift up the carpet and there is an access panel for the fuel pump.

Not sure how many miles are on your rig but the old age will get them too.

I change them out as part of PM so no one gets stranded.

Here is a Denso fuel pump for a 2002 LC

https://www.amazon.com/Denso-950-0107-Fuel-Pump/dp/B00274QIVM

Let’s know if you get it figured out.

 

[outdoorsman]

Fuse location

Fuse block diagrams

 

[sailor95]

I have already replaced the fuel pump today, we got it to run after letting it sit for a while then letting it prime and crank but once i got it home we cant get it to restart again and there is fuel in the lines on the engine side of the fuel filer so im real stumped now

 

[sailor95]

Still cant get it to start, anyone?

 

[outdoorsman]

Let’s try to narrow this down. It is either a fuel or electrical problem. We are here to help.

When you turn on the key does the fuel run, build up pressure and then shut off?

When it starts does it seem to run fine? Or does it run rough and die?

Do you have a check engine light on?

Could you have gotten some bad gas? Did this happen after you got gas? Water settles to the bottom and could be a problem after letting sit over night. When the fuel pump was out would have been an easy time to check for water in tank. You can get water finding paste and put it on a piece of wood and dip it in the tank.

When it is not starting have you made sure the sercurity light is not flashing ?

Have you had any issues before this started?

Just some thoughts fuel filter clogged, bad fuel pressure regulator or electrical problem.

 

[sailor95]

I think the fuel runs because there is fuel on the other side of the filter in the engine bay, when I turn key I don't hear anything coming from pump but its always been quiet. When it ran after replacing fuel pump it ran fine and normal but I did notice a whine coming from fuel tank area with window down, but its a new pump so that's def weird right? Because after shutting it off it wont restart. I don't think bad fuel because I go to the same couple places around Statesboro and never mess with rundown or older stations. I do not see any security light flashing. I had an issue with it last summer in Colorado after a large decrease in altitude from Westcliffe to The great sand dunes and it left me stranded at a gas station, sat at a shop in that area for a few days and the mechanic just showed me he beat on the gas tank and got it to start. Drove it all the way back to Georgia with no problem and this is my first problem since that time last July. Where would the regulator be and what would be the method to test it?

 

[outdoorsman]

2002 LC100 - Not Starting... ??? Fuel Pump ???

 

[sailor95]

I think i got the problem, replaced the efi fuse and it started and is now running well

 

[flintknapper]

I think i got the problem, replaced the efi fuse and it started and is now running well

^^^^^^ Yes, and if it happens again....be sure to check behind the fuse board for corrosion or evidence of that connection getting hot.

Also, I don't think you will hear the fuel pump 'prime' when turning the key to the on position, I think it only activates while actually cranking the engine.

But someone please correct me if I am wrong about that.

 

[Spike555]

^^^^^^ Yes, and if it happens again....be sure to check behind the fuse board for corrosion or evidence of that connection getting hot.

Also, I don't think you will hear the fuel pump 'prime' when turning the key to the on position, I think it only activates while actually cranking the engine.

But someone please correct me if I am wrong about that.

The fuel pump comes on and runs for less than 10sec to prime the fuel system and then shuts off if there is no signal from the crank sensor.

 

[jerryb]

nope, if you study the diagram of the fuel system you'll realize that it does not run until the engine is cranking.
I have a QD on the rail and tested this more than once before I looked at the wiring book.
Without a leak the 100 fuel system will hold greater than 75% of running pressure for more than a day. There's no check valves in the system either.
Also, I have a walbro pump in mine, if it ran at any point before starter engagement I would know.
I'm strictly talking about the drive by wire 100s.

 

[flintknapper]

The fuel pump comes on and runs for less than 10sec to prime the fuel system and then shuts off if there is no signal from the crank sensor.

You might double check. I'm pretty sure this isn't the case.

 

[sailor95]

Well thank you all for the information, day 2 after cranking and still running well, i replaced with the denso and i swear it idles better and shifts a bit smoother. Given the pump in there was almost 20 years and 343k miles old i think this a needed replacement

 

[flintknapper]

Well thank you all for the information, day 2 after cranking and still running well, i replaced with the denso and i swear it idles better and shifts a bit smoother. Given the pump in there was almost 20 years and 343k miles old i think this a needed replacement

^^^^^^ While I would never recommend replacing a fuel pump as 'preventative maintenance', in your situation it was not a bad decision to replace that component in your search for the problem.

Mine (99 LX470) started 'whining' and cutting out right around 190K.....conversely, I have the original fuel pump in my 80 series with 299K (21 yrs. old) on it. So go figure.

Glad you are running smoothly again and hope it continues that way for you.


Flint.

 

[sailor95]

Even if it doesn't. I'm saving for a replacement engine, I've had the Hundy since i was 16 and have no want to drive anything else, cheaper to replace and keep cruising than go buy anything new.

 

[Dannyboy lx470]

I'm not sure if I'm having fuel pump issues.Car starts when cold ,but if I switch it off still cold will only restart if I give it gas on pedal.Noticed my starter has started to sound different to.