No return line is a real surprise.
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SQOD Squad - Stupid Question Of the Day (4 Viewers)
- Thread starter JamesC
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bloc
SILVER Star
I'm looking at the diagrams, there is no return line. There isn't even a traditional fuel pressure regulator as on the common-rail diesel systems I've worked on.
My guess is the pump allows excess fuel from the high pressure side to bleed off back into the inlet.. there is some sort of electrical valve on the HPFP, but it's not a separate part so would be hard to research the operation.
But, even the low-pressure side doesn't have a return. Other manufacturers went to returnless systems years ago, partly to control evaporative emissions.
Return inside the HPFP makes sense. I guess a centrifugal type fuel pump would just deliver some more pressure and less rate when the engine idles
This makes engineering sense. At the much higher pressures of GDI there isn't the need to flow fuel to keep the temps down and therefore inhibit vapor lock. As long as the pump has a way to keep itself cool and lubricated the injector line can be a dead-head system.
With GDI being more expensive to manufacture, the savings of a return system probably offsets this as well as eliminating a few potential failure points.
With GDI being more expensive to manufacture, the savings of a return system probably offsets this as well as eliminating a few potential failure points.
bloc
SILVER Star
Interesting you mention that. Yes, this implementation is expensive.. because it has a whole GDI system but still keeps a port injection system to keep the valves clean and I'm sure for other tuning purposes. Technically more failure points, but port systems have been done similarly for so long I'm assuming they felt the valve cleanliness benefit was worth the cost and at least predictable complexity.
On my direct injected I-6 535 diesel the HPFP gets a steady 3.95 to 4 bar from the pump in the tank with a return line. The HPFP delivers to the injectors anywhere between what I can see in BimmerLink at 200 to 1800 bar full load. There must be some adjusting mechanism in the fuel pump to facilitate for this.
So there are different setups and I must say I have not researched this to understand why let alone know the pros and cons.
So there are different setups and I must say I have not researched this to understand why let alone know the pros and cons.
bloc
SILVER Star
I know from experience with them VW and MB's early (at least) common rail diesel setups used a separate pressure regulator mounted on the fuel rail that did control pressure by bleeding excess back to the tank. From a quick search GDI runs at a whole lot less pressure than Diesel, so maybe that allows different strategies?
Also I don't believe evap emissions are a concern at all with diesels...
Hi all - my mud search skills are lacking. There must be a link to a list of the HVAC error codes for a 200 Series, right? I haven't been able to find it. I didn't think starting a whole thread was necessary. I found the instructions for pulling and resetting the codes from the HVAC system, but I want to find a list that explains what each code means.
This is a 2019 LC. I replaced the cabin filter with no issues or damage. The main problem is that when I increase hvac fan speed, I can hear the blower working harder but the output from the vents is lacking. The temp changes like it should but it just doesn't output as much air/heat as it should.
I have 4 codes: 48 49 57 86
I will reset them but I still want to know what the codes mean, particularly if the problem persists.
This is a 2019 LC. I replaced the cabin filter with no issues or damage. The main problem is that when I increase hvac fan speed, I can hear the blower working harder but the output from the vents is lacking. The temp changes like it should but it just doesn't output as much air/heat as it should.
I have 4 codes: 48 49 57 86
I will reset them but I still want to know what the codes mean, particularly if the problem persists.
Get the fsm. It typically has troubleshooting steps for each code in it.
Have you tried resetting the HVAC servos? There are several motors (servos) that have to be synched for the system to blow air in the right places.
Climate servomotor initialization PSA
Hey y'all passing along a life changing thing I didn't know about. But apparently when disconnecting the battery you may need to re-initialize the climate servomotor(s). Last two summers I've noticed significantly less air volume coming out my vents despite a rowdy full blast fan. I initially...
forum.ih8mud.com
Seems if all was working pre filter change and you did not damage the door that the filter you bought is perhaps to good i.e. filters to much. I understand that can happen with an aftermarket filter.
Still reading the codes could be helpful then again it can confuse you as well. For example disconnecting the main battery can cause stored codes without there being any issue. I typically on my own vehicles and those of the kids check 1) there is no strange mechanical noise and 2) there is sufficient oil in the engine, then I first clear all codes and lastly drive the car to see whether a CEL or a code comes back. Still trouble shooting based on a “true” trouble codes requires understanding of the system or subsystem you are dealing with. This forum can be great for that.
Good luck, keep us posted.
2HundyJTex
SILVER Star
Anyone know if this need to reset servos also applies to 2016-2021?Have you tried resetting the HVAC servos? There are several motors (servos) that have to be synched for the system to blow air in the right places.
Climate servomotor initialization PSA
Hey y'all passing along a life changing thing I didn't know about. But apparently when disconnecting the battery you may need to re-initialize the climate servomotor(s). Last two summers I've noticed significantly less air volume coming out my vents despite a rowdy full blast fan. I initially...
Yes, same system
Here's a couple from me.
Is the PRND panel supposed to light up, be illuminated, at night? What is the box thing with the slot in the glove box? And is there an aftermarket black/blacked out trim piece available to replace the stock chrome one? (that says LAND CRUISER across the back hatch)
Is the PRND panel supposed to light up, be illuminated, at night? What is the box thing with the slot in the glove box? And is there an aftermarket black/blacked out trim piece available to replace the stock chrome one? (that says LAND CRUISER across the back hatch)
No, those don't light up, there's a display of the selected gear in the center of the dash gauge cluster.
That slot is to upgrade the DVD of the maps in the navigation system.
Thanks to everyone who responded. I reset the codes and nothing has come back since. I did go through the process of setting up the FSM on my computer. Below is the chart for the HVAC codes, for reference. I did not reset the servos because everything seems ok for now. I will keep that one in my back pocket (as the codes were relevant to the servos).
Lights are done. I think it turned out great! My wife not so much, but she doesn't drive it anymore…. I also made a build thread inset the MB section.
forum.ih8mud.com
Mercedes - W211 e320 “rally build”
I have been on mud for years. In the last >30 years I’ve had a 60 series, 80 series and now 200 series since 2013. We have also owned a 2004 MB e320 4matic we bought new late 2003. My wife drive it for 15 years now my teens drive it. Anyway this past fall my daughter (who usually drives her...
forum.ih8mud.com
terrapin
SILVER Star
Does anyone know if the replacement key fobs sold by replacemyremote.com (and others) support remote starting? Mine is FCC: HYQ14AAB and has the letter "E" on the bottom right corner of the circuit board.
Also, the website says that it is refurbished. Do they just replace the case and emergency key or what.
This is the one I am looking at for a 2010 LX570.
replacemyremote.com
Also, the website says that it is refurbished. Do they just replace the case and emergency key or what.
This is the one I am looking at for a 2010 LX570.
2008 - 2016 Lexus 4 Button Smart Key w/ Hatch - Emergency Key Included - E Board - HYQ14AAB
<p>2008 - 2016 Lexus 4 Button Smart Key w/ Hatch - Emergency Key Included - E Board - HYQ14AAB</p> <p><strong>This remote has been wiped/cleared of any previous programming and is ready to be programmed to your vehicle!</strong></p> <p>In the event your automotive locksmith has trouble...
I am going to replace the driver's side window, it is not broken but at one point something scratched the glass on the inside as there is a nice vertical scratch. Perhaps a small rock or something was caught in the molding. There are also a bunch of light scratches, also on the inside. I am guessing the PO had a dog that scratched at the window. Nothing terrible but enough it bugs me.
Anywho I am about to take a look at what is involved in removing the door panel and other trim bits. I read a previous thread on an older LC200 that had channel for the glass whereas my glass has two tabs. Before proceeding I thought I would inquire if anyone has any guidance. Thanks.
Anywho I am about to take a look at what is involved in removing the door panel and other trim bits. I read a previous thread on an older LC200 that had channel for the glass whereas my glass has two tabs. Before proceeding I thought I would inquire if anyone has any guidance. Thanks.
I replaced my driver and passenger side windows to laminated versions from the LX570 purchased on eBay made by as pretty big chinese car glass manufacturer. Been to really happy with the same and no down sides for a side window without the Lexus or Toyota logo.
It’s pretty easy to do. I think I did a write up with some picks at some point. Try searching for it please.
