P0089 - Low Fuel Pressure LR4
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Have you had the fuel flange recall done yet? I've gone round and round with the code you're asking about. There actually should be 2 more digits after that code. Those last 2 are kind of important because they differentiate between erratic signals, low or high signal. The general drift of the code is that the computer doesn't like the duty cycle running your fuel pump. The PCM sends pulse width signal to the fuel pump driver and the fuel pump driver uses that to increase or decrease fuel delivery. The PCM likes the dwell to be under 30% if I remember correctly.
It's a sign that your pump is getting weak. I asked about the flange recall because I've fixed them with just the flange before. I think the check valve that holds fuel up in the lines is in there. I used to replace both the flange and the pump. A service writer didn't sell the flange once to save a guy some money. I just put the pump in and the car still had the fault on cold start. I put the flange in, and it fixed it. So, if you haven't gotten the recall done get that done first, I suppose. But keep in mind you could get the pump put in at that time with little or no labor.
It's a sign that your pump is getting weak. I asked about the flange recall because I've fixed them with just the flange before. I think the check valve that holds fuel up in the lines is in there. I used to replace both the flange and the pump. A service writer didn't sell the flange once to save a guy some money. I just put the pump in and the car still had the fault on cold start. I put the flange in, and it fixed it. So, if you haven't gotten the recall done get that done first, I suppose. But keep in mind you could get the pump put in at that time with little or no labor.
Damn, unfortunately, the flange was done about 6 months ago. My wife drives this so I’ll need to see if the code was thrown again today. If so, I’ll use a different code reader bc I don’t think the one I used yesterday gave me more digits. I could be mistaken tho.
Our LR4's fuel pump died after the flange was replaced... But in two instances - one when pump controller died, another when the pump itself died, no codes were logged, no CEL, nothing. As if I simply ran out of gas.
Interesting you say that. We’ve seen some of that fuel pump failure after the recall. One of these young guys who’s done a ton of them just had it happen a couple times in a row. We took one apart and looked at all the connectors and put it back together. It ran for a little while and quit again.
Somethings going on and I’m not 100% sure it’s the guy doing the job.
Yes it's worth a shot. But don't be surprised if it still has the problem. But definitly worth a shot if hasn't had PCM software in a while.
Any guesses on what dealerships charge for this type of service? The upsell they push at the dealerships im familar with is akin to going to the dentist.
2 fucking K? That’s like at least 1500 in labor. Run like hell. Write a letter asking how they came up with that #. Cause somebody is stealing.
Yeah, these dealerships in the mid-Atlantic have balls and 9/10 of their customers don’t. I have an indie shop I’ll work with. I like to do as much homework as I can to keep from using any more of his time as possible. He’s got Autologic, so we’ll figure out tomorrow whether it’s the high or low pressure pump that I need.
It’s the low psi pump. He needs to watch the command from the PCM to the fuel pump driver. It’s probably too high. Which means the pump is running more than the PCM likes to maintain the pressure it wants in the rail
Autologic says high pressure pump, so HPP it will be.
As you may expect, when I got under there to start pulling the first pump, lo and behold more signs of stellar JLR quality. T-stat is leaking and looks like trans cooler lines. Gonna just leave the idiot shields off so I can spot leaks earlier and more often. Seems their primary purpose was to defer customers catching leaks during the warrant period anyway. That’s my theory and I’m sticking with it as my WP has failed twice, all coolant hoses and now tStat and trans cooler hoses. Good grief.
As you may expect, when I got under there to start pulling the first pump, lo and behold more signs of stellar JLR quality. T-stat is leaking and looks like trans cooler lines. Gonna just leave the idiot shields off so I can spot leaks earlier and more often. Seems their primary purpose was to defer customers catching leaks during the warrant period anyway. That’s my theory and I’m sticking with it as my WP has failed twice, all coolant hoses and now tStat and trans cooler hoses. Good grief.
I will be shocked too. But since it looks like your going thru with it you might want to drain some oil out of it. Cause those pumps are below the oil level.
What we did is followed the procedure in this YouTube below. The readings of Fuel Rail Pressure and Fuel Rail Pressure-Desired could not get to 4800 or above. The readings were low 3’s. The other readings were in the ranges the video mentioned was acceptable.
Anything odd/wrong with this procedure?
Anything odd/wrong with this procedure?
All that is just data. I’m sure your high pressure stuff is working correctly. So all that data is really irrelevant to the code you’re looking at. When you dig down into that code in the info I have available to me, it’s picking on the fuel pump commanded duty cycle. The low pressure fuel pump in the tank. The one that’s driven by the fuel pump driver using that command from the pcm.
When I’ve seen this code it would throw the light on the first cold start of the day. It was throwing it because the duty cycle was climbing as high as 33%. Once it was fixed it would stay down around 27%.
Can I have your old high pressure pumps? I’ll pay shipping.
When I’ve seen this code it would throw the light on the first cold start of the day. It was throwing it because the duty cycle was climbing as high as 33%. Once it was fixed it would stay down around 27%.
Can I have your old high pressure pumps? I’ll pay shipping.
Why are they trying to diagnose the high pressure fuel pumps when the fault is for the low pressure side? I’d suggest finding a new shop.
I found that if you enter the wrong year when looking up that code you find no listing of it. I can’t remember what year LR4 this is. But it’s easy to get confused. Then there’s info online about other manufacturers that single out the high pressure pumps with this same code.
It’s a hard world and this is exactly the kind of shit that makes me say fixing these cars is a game designed to humble the mighty.