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Does anyone know if the 2008 GS460 share a fuel pump assembly with any other GS or LS vehicles?
I have a suspicion I have a fuel pump issue / fuel filter issue and was going to get one from a wrecked car. Obviously I can find a GS350 or LS460 but not sure if they the same.
www.car-parts.com cross references many parts and will tell you which cars use the same pump. I did your car and shows the whole fuel assembly is different, but the pump alone is the same as gs and is, as for the engine mounted pump the ls460 is the same.
That being said, its very rare for our fuel pumps to go bad. I would do actual testing before replacing parts. What is the car doing that makes you think the fuel pump is bad?
Thanks for that, good to know. Explain why I was getting mixed results! Haha.
Filled the car up from empty and it started having serious engine hesitation issues. Looks like car isn’t commanding the throttle body open all the way.
Have had two mechanics inspect, throwing no codes, fuel trims and timing look good, MAF replaced, have put fuel system and injector cleaner through it and replaced gas cap. O2 Sensors look okay and I can see before and after temperatures of CATS look good. Has had at least two full tanks of gas through it since it started.
Has been going between bad and really bad for a few weeks with 1 or two days being perfect. It’s very strange.
Waa going to maybe test resistance of fuel pump and see if I can test the low pressure with a gauge?
Have you had the throttle body cleaned inside and out? Spark plugs are they oem or denso original and not knock offs?
When the car was having issues, was the engine pinging? If theres pinging could be a sign of low fuel or a stuck injector. btw pour in fuel cleaners barely do anything to clean your fuel system, I wouldnt waste money on them.
Have you checked for air leaks from the air maf to the throttle body to make sure no hoses are loose. I doubt your issue is the fuel pump, but you can plug a fuel gauge to fuel system and test the psi.
I think you might have better luck diagnosing this issue in the LS460 group as you guys share the same motor
Thanks. I’ve had a look between MAF and motor but couldn’t see any cracks. I was meaning to check on the little resonator though as I saw someone mention that.
I was planning on inspecting throttle body today to see how dirty it is. I would think it’ll have to be pretty bad to cause these symptoms being all over the place.
Not sure on spark plug brand, I just know first mechanic check them and said they were good.
Good idea on LS section, I might try these extra few things and then summarise and post in there. The auto electrician did say if MAF didn’t work that they have a few more paths they want to go down. It’s just painful spending all money with mechanics for a mystery problem haha.
Thanks. I’ve had a look between MAF and motor but couldn’t see any cracks. I was meaning to check on the little resonator though as I saw someone mention that.
I was planning on inspecting throttle body today to see how dirty it is. I would think it’ll have to be pretty bad to cause these symptoms being all over the place.
Not sure on spark plug brand, I just know first mechanic check them and said they were good.
Good idea on LS section, I might try these extra few things and then summarise and post in there. The auto electrician did say if MAF didn’t work that they have a few more paths they want to go down. It’s just painful spending all money with mechanics for a mystery problem haha.
When you said you had serious hesitations, what was the car doing exactly? Did you try to floor it and the car wouldnt go faster? Did the rpm gauge move or go blank? Did the hesitation start from nowhere then slowly get worse? Did it fix it self or clear up? Did you try restarting the car to see if it changes anything
MAF sensor rarely go bad! They do get dirty and just require a cleaning, especially if you dont change the air filter. Regarding the throttle body, I would unbolt the throttle body and fully clean it, inside and out. you can use wd40 to clean the throttle body.
I would avoid a mechanic that is guessing, rather I would rather see you take it to someone who can properly diagnose it. Usi
So it very much feels like someone is putting the throttle out from under you. It’ll rev through the range but very slowly.
Sometimes it gets so bad it’ll shudder when you try a small amount of accelerator. Then there is the odd moment where it feels 100% fine.
When it got bad I reset battery and drove it and it was pretty good for a few minutes.
Pretty hard to put finger on. I’ve owned car for 3 weeks. The old owner said if didn’t have this problem (obviously could be lying but seemed like a nice guy). I picked up a friend, gave it a few first gear pulls when empty light just came on. Filled up a full tank. Then leaving gas station is when it all started. This timing is why I keep thinking fuel related
I can see high pressure fuel rail readings with scanner but can see anywhere online what these should be under load.
Filled the car up from empty and it started having serious engine hesitation issues. Looks like car isn’t commanding the throttle body open all the way.
That sounds like you got some bad fuel if you weren't having any problems before the fill up.
Yeah the only catch is I’ve probably done 2-3 full tanks of gas since then. So all I can think of is block filter from some debris? Or fuel pump isn’t proving enough pressure and doing a few hard pulls while low hurt it somehow.
Too me it kinda sounds like a clogged fuel injector on the high pressure injectors. You could remove all the fuel injectors, buy new oem o-rings and take them to a fuel injector cleaning shop. They can test and monitor each injector, there should be 16 injectors total. 8 regular and 8 high pressure.
Too me it kinda sounds like a clogged fuel injector on the high pressure injectors. You could remove all the fuel injectors, buy new oem o-rings and take them to a fuel injector cleaning shop. They can test and monitor each injector, there should be 16 injectors total. 8 regular and 8 high pressure.
Yeah could be an idea. Would a clogged fuel injector cause no issues to fuel trim, no error codes and inconsistent issue though?
Yeah could be an idea. Would a clogged fuel injector cause no issues to fuel trim, no error codes and inconsistent issue though?
Yes, a clogged injector can limit rpm, give hiccups, sometimes pinging. Sometimes it would drive fine, then out of nowhere give you issues.
If im not mistaken fuel trim measure the signal power to the injector, from the ecu. but if you have several clogged injector tips then it wont show flow coming out. You could also have injectors sticking open.
My advice take it to a good mechanic/specialist, tell him you suspect the fuel injectors let him see. Probably the spark plugs should give clues to what the injectors are doing.
If im not mistaken bad fuel injectors on ls460's is an issue I have seen several times.
Hmm one thing that’s interesting. If I pull the battery for 10min the car has near 100% power again. Computer is instructing the throttle to open to 88%.
Then it just slowly goes back to performing badly.
Wonder what’s being reset temporarily to “fix” this.
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Does the GS460 share a fuel pump assembly
