NX2K lag in low end acceleration

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After searching this forum for over a year on this problem and doing many, many things related to my problem i still am at square one.


93 NX with a fresh SR20DE swap (40K) orig tranny....5 speed

I have very little low end (1st, 2nd gear) punch the car makes alot of noise but does not really do anything. Once i get up tp 3rd and higher it starts to take off!

THe loud engine noise that goes along with the lack of low end punch is similar to a bad mount or hub, if i turn the wheel to the left it goes away and sounds normal.\\\

....also some waiver in accel as i get up to 5k+ revs (have re grounded maf and cleaned egr, best i can)


Please Help!!!!! any suggestions welcome thx
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over easy

well i got that problem on my dirtbike. i took the exhaust off and cleaned it. and sprayed all kinds of carb cleaner in the valve area. i think with my case its the carboned powerrange valve in there i need to soak all that too.
i dont think i helped u at all

Where's the timing set at? Changed the fuel filter? Just throwing some ideas out there man I hope you get this figured out.

maybe a seized up power steering pump.

maybe a seized up power steering pump.

I would guess something similar, a pump could cause a lot of drag until the engine gets on top of the rpm range, and it would make nasty noise. I don't see how turning the wheel would have an impact on almost anything else, unless there is an issue with an axle bearing or another axle part. Turning the wheel might relieve load on a partially binding axle if the bearing was toast at the inner splined end. That also might make the kind of vibration you'd associate with a bad mount.

You don't say how it runs when you are just stationary with the clutch in or the car in Neutral. How does the motor run when there's no load on it?

Does the turning of the wheel do the same thing in both directions, or only one?

You need to figure out if the problem is 1) motor only, 2) motor + acc like the PS pump, 3) front drivetrain related, or 4) none of the above.

yeah thats true I didnt think about the vibrations/bad mototr mount claim he made. In that case it'd be something along the drive line. I just always thought it was pretty obvious when an axle goes bad LOL

Thx sooooo much for taking the time to reply.... The car idles fine with clutch in or out (there is a slight noise from clutch area when idling with clutch out) just changed clutch along with new T/O bearing etc..may just need cable adjustment.

After the pump info you said above i looked and found a slight leak at the pressure hose!

Both axles have been changed and the bearings both side but not the entire hub.

Just to clarify the noise goes away when i turn the wheel to the left...even going staight and right causes a pretty loud sound so much so that the engine sounds like it reaching redline when only at 5K!!

Timing is set to 19 with premium gas only being run.

if i am leaving any potential info out let me know..once again thx for all the help.

Once i get this sorted its paint time and pics of the 3 year restoration to follow ...thw entire project was done using info and help from the forum alone!!!!!!!project. Andy

Ok, no improvement you turn off center to the right? Why I ask is if both directions, then that points to when you start applying steering angle the pump somehow things smooth out from what I can understand. I believe this pump like a lot of them is self lubricating with the fluid, has it ever been down much on fluid? Can you hear any unusual noises from the acc side of the motor?

Remember a little movement on the PS res dipstick may take quite a bit of fluid to fill. Make sure it's full enough to reach the H line when the car is warm.

Have you considered backing off the timing a degree or two temporarily? Did you have any fuel-related mods or are you running other than a stock ECU? Were the injectors replaced or cleaned as part of the work done over the last few years?

Have you checked the output voltage or replaced the front O2 sensor? That can also cause problems if it has never been replaced. An extra ground wire O2 sensor is a good idea too if you're using a header.

Has the motor ever run well since you've had it? I mean was there a point in time when it ran well then gradually didn't? If so, what if any work was done during that period?

HTH and good luck, there are only so many possibilities but I really have to wonder if the engine management plus advanced timing isn't working out. If you run a stock ECU and advance the timing like that, it will be hyper sensitive to knock and increasingly pull back the timing as you rev the motor. That's why I ask what you're using for tune other than a base timing advance, and any non-stock or changed fuel delivery.

If the motor has never run well, then you may very well have some basic things to check - you might have distributor problems, injector problems, etc. Also check to ensure you don't have oil leaking into the cap/rotor, that's pretty common leak and makes a mess of the distributor.

Great info, thx once again. Alot of what you mention i have done and should of included in my question: I have


Replaced from ox sensor (new non splice)

Motor has always run strong and even before i advanced timing i had same problem, the advance was a possible remedy to the issues i was having.

I used the fuel injectors that came on the new jap motor as the orginal ones off the motor were clogged.. i did not clean them other than running cleaner,,,seafoam through the whole system once insatalled.

No mods other than a k&n cone air filter.

note; When i got the car from my friend is was f...ed sooo much carbon and crap through the egr system etc i have tried to clean as well as i can,\\

Again i do notice a little leak at the p/s pressure hose but not much.

what do you think on bad motor mount or entire hub causing this issue



cheers mate!!!!!!!!!!!!!!!!!!!

Long shot but have you checked the condition of the ECU? Sometimes I see water damage there, and if you have a spare might try swapping it temporarily.

Also when the swap went in new trans or old one? If new are you sure the driver's side axle is right match for LSD/non-LSD trans?

One thing not clear on is when the car isn't moving does the engine rev normally up and down the rpm range, or does it always make this loud noise below 3k whether it's moving or not?

You'll get it sooner or later, there's only so many possibilities. A lot, but it's not that complicated by today's standards.

same tranny

revs at idle perfect

noise only in motion going straight and to the right

what does a bad hub/spindle sound like?? i have just replaced the bearing thats all

can you listthe most common causes of loss of punch/accel on the sr20


thx once again andy