Throttle Lag
#46
#47
My car has been running much better in DS and pseudomanual. It feels like a totally different car.
Unfortunately, I have a new problem. There's a weird rattling noise that seems to be coming from under the driver side dash. It happens under heavy load, mostly over 4k RPM. The local mechanic thought it might be a bad fuel pump, but isn't that located at the rear of the car? I also wonder if it could be some kind of sabotage, as I've been arguing with neighbours over them scratching and dinging my car and they've responded by spitting on the vehicle and even stealing a wheel centre cap.
Oil consumption is getting really bad too, but two mechanics have said it's not a big deal as long as I keep topping it up.
I'm not ignoring you, Serge. I just don't have the mechanical expertise to help.
Unfortunately, I have a new problem. There's a weird rattling noise that seems to be coming from under the driver side dash. It happens under heavy load, mostly over 4k RPM. The local mechanic thought it might be a bad fuel pump, but isn't that located at the rear of the car? I also wonder if it could be some kind of sabotage, as I've been arguing with neighbours over them scratching and dinging my car and they've responded by spitting on the vehicle and even stealing a wheel centre cap.
Oil consumption is getting really bad too, but two mechanics have said it's not a big deal as long as I keep topping it up.
I'm not ignoring you, Serge. I just don't have the mechanical expertise to help.
#48
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Yes the fuel pump is located under the rear seat but there is a fuel pressure dampener in the engine compartment near the firewall on the passenger side. As far as I know it doesn't make any NOISE when it's failing though, I suspect maybe your cabin air filter has wiggled loose or something. Remove the big plastic cover over the battery compartment held down with a half dozen ***-snaps (use a small flat blade screwdriver to "lift" the center plug and they pop right out) and you can look to see if something is loose on the cabin air filter.
Can you reproduce the rattling with the vehicle in park or is it only while driving?
Yes oil consumption is "normal" for the engine but if it has drastically changed recently and you are consuming MORE than 1qt per 1k miles then you have a serious and growing problem that needs to be addressed. Switch back to conventional if you are currently using synthetic and start shopping for a new motor if it gets any worse than that.
Sucks having a war with the neighbors, move out into the rural areas so you don't have neighbors anymore
Can you reproduce the rattling with the vehicle in park or is it only while driving?
Yes oil consumption is "normal" for the engine but if it has drastically changed recently and you are consuming MORE than 1qt per 1k miles then you have a serious and growing problem that needs to be addressed. Switch back to conventional if you are currently using synthetic and start shopping for a new motor if it gets any worse than that.
Sucks having a war with the neighbors, move out into the rural areas so you don't have neighbors anymore
#49
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#51
#52
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I mean it's -probably- fine but like you said, it's impossible to know for sure without seeing a video or being there in person. You might save yourself a diagnostic fee and lift the vehicle to make sure your heat shield on the catalytic converters isn't loose and rattling. This is a known issue and the sound could simply be echoing up and making it sound like it's from under the dash. The cats are in that vicinity.
#54
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#55
OK. I hope it won't be too expensive, but I suspect it will be. I'm probably going to need new valve covers, plus whatever is required to fix the ticking/rattling sound, plus something to deal with brake judder. It's also going to need new pads soon. I'll have to decide whether to bother fixing all of that or just sell the car.
#56
Yes seems like an engine rpm induced vibration, might be exhaust related or a plastic cover/guard. I would go to a aftermarket Nissan specialist shop, or barring that even a general performance shop that deals with Honda's, Subaru's etc, as well, probably get more attention to detail and better support for less $$. If your best hope is taking a 10year old car to the stealership i would probably bail.
Also not sure why you're burning that much oil with relatively low mileage or why your car would drive better in DS? Perhaps its tranny related. Just puttering around town with the occasion squirt through the rev band should not be any different in D or DS
As far as brake judder upgraded rotors look to be the cure for this (or at least a vast improvement) I've learned how to modulate the brake pedal to in effect 'turn' the rotors with every stop, keeping them relatively warp free.
Also not sure why you're burning that much oil with relatively low mileage or why your car would drive better in DS? Perhaps its tranny related. Just puttering around town with the occasion squirt through the rev band should not be any different in D or DS
As far as brake judder upgraded rotors look to be the cure for this (or at least a vast improvement) I've learned how to modulate the brake pedal to in effect 'turn' the rotors with every stop, keeping them relatively warp free.
#57
The problem with local shops is that they're scratching their heads and refusing to touch things. I live in a small Korean city where they're not used to seeing Infiniti vehicles. Most people are driving Hyundai and Kia cars which are simple and run forever (they never get driven hard).
I wonder if the local mechanic who screwed up the throttle body cleaning did something that led to this vibration. He supposedly specialises in imported vehicles, but it's possible he's just pretending to be an expert at something he's not.
The car is fairly sedate in D unless you're launching from 0. If you're telling me that's not normal, then I guess I have a transmission problem. In DS, it revs a lot more, downshifts much faster, but tends to hold high revs for up to a few seconds even when my foot is off the throttle. Is that also abnormal?
It seems like there's a lot that needs to be done. It looked to be in good condition when I bought it in March for $9000, which is above the average market value. I hope I didn't get screwed by someone who did a bunch of cheap temporary fixes on a shot car.
Oh, one thing about the exhaust. It was replaced shortly before I bought the car, but it was installed too low so it constantly hits speed bumps. I also had one incident (around a month ago) when driving up a ramp where the underside of the car hit the ground which led to a sudden jump in engine revs and a loud clunk. I don't have any tools (I live as an expat in an apartment block) nor much mechanical skill, but I'll try to look underneath as best I can and then report back.
Final edit: Perhaps oil leaking from the valve cover has damaged the spark plugs?
I wonder if the local mechanic who screwed up the throttle body cleaning did something that led to this vibration. He supposedly specialises in imported vehicles, but it's possible he's just pretending to be an expert at something he's not.
The car is fairly sedate in D unless you're launching from 0. If you're telling me that's not normal, then I guess I have a transmission problem. In DS, it revs a lot more, downshifts much faster, but tends to hold high revs for up to a few seconds even when my foot is off the throttle. Is that also abnormal?
It seems like there's a lot that needs to be done. It looked to be in good condition when I bought it in March for $9000, which is above the average market value. I hope I didn't get screwed by someone who did a bunch of cheap temporary fixes on a shot car.
Oh, one thing about the exhaust. It was replaced shortly before I bought the car, but it was installed too low so it constantly hits speed bumps. I also had one incident (around a month ago) when driving up a ramp where the underside of the car hit the ground which led to a sudden jump in engine revs and a loud clunk. I don't have any tools (I live as an expat in an apartment block) nor much mechanical skill, but I'll try to look underneath as best I can and then report back.
Final edit: Perhaps oil leaking from the valve cover has damaged the spark plugs?
Last edited by sjwtriggerer; 12-07-2017 at 07:57 PM.
#58
The car is only sedate in accordance with the weight of your right foot, what you're describing is normal, it does downshift less eagerly and not hold the revs as much in D, however a prod of the accelerator will bring the engine to life quite quickly. I use D 99% of the time as I don't require or do much sport driving.
P.S. I'm on the original flash with the more aggressive throttle tip-in so that may have something to do with it.
P.S. I'm on the original flash with the more aggressive throttle tip-in so that may have something to do with it.
#59
#60