unresponsive accel. feels jumpy sometimes

[zain1003]

Well this has been happening for a couple months so i decided it would be worth my while to see what the nico community has to say about it. my 90 n/a 5spd has been running well except for a couple things.

1. around 1300-1900 rpm in any gear, the car SOMETIMES feels a little jumpy. what i mean is that the rpms go up and down +-100 about 4 times per second so its very quick. this gives me the same feeling as when a car is about to stall. during these rpm ranges, my accelerator feels spongy, as in it feels less responsive compared to normally and i dont get the adequate acceleration out of it. i this issue happens more often when its really COLD outside, or if i drive the car before the engine has warmed up (i rarely ever do that anymore)

2. I have a coolant leak..somewhere...i refill my radiator about once a week. ( i added that to give more info, maybe the problems are connected)

3. also there was only 2 or 3 times during the middle of winter when it was below freezing at times when i drove the car on a cold engine (only heated for a minute or so) and the cars rpms dropped massively when i began to let the clutch out. i stopped and heated my engine up and it happened a couple more times and then hasn't happened in a month or 2

I thought id post and see if anyone knew what it could be.
Thanks.

P.S. how do you remove the door pannels? i need to install my new speakers since my old ones blew out. directions on how to install the front 3.5s and/or the back 6.5s would greatly be appreciated, since i have brand new ones just sitting here.

[Ace2cool]

Have you tested your Throttle position sensor? Run ECU diagnostics to see if you can pull any codes and have a lead to go off of.

[zain1003]

Have you tested your Throttle position sensor? Run ECU diagnostics to see if you can pull any codes and have a lead to go off of.

i just looked up how to do that yesterday so ill be doing that at some point this weekend.

[dantesdoom]

About the doors...they are tricky. you have several screws to remove from the door on the inside and one from the OUTSIDE from the circle behind where the glass rolls up at....there are also numerous clamps on the door panel. I figured it out when i removed my bose system and replaced with Kenwood. For ease of use, here is how to get to the speakers....mind you, the rears are an absolute b**** to get to....you have to remove all of the rear panels to remove the shock tower covers....so if you need new rear shocks, go ahead and do them at the same time. Here is a link to show how to do it all. Just scroll down to stereo installation on his z32 1992 tab. This guy outlined everything in detail, he is a god in my eyes.

http://www.twinturbo.info/

BTW if you have a four seater, you will need to remove the seats and panels beside them to get the last screw by the shock tower for the rear ones if you are going to do them. Also the stock speakers were quite small, so if you have the Bose system and you want to upgrade to 6.5 in the front you will need OEM brackets or PVC ones... Also, the rear took like 4X6" stock, so, youll need brackets for them as well if you want to do a standard 6.5" all the way around.

Stock ones, that only go to 5.25" and EXPENSIVE
http://www.z1motorsports.com/product_in ... ts_id=3875

Stock rear
http://www.z1motorsports.com/product_in ... ts_id=3838

PVC for front to 6.5"
http://cgi.ebay.com/Nissan-300ZX-Front- ... _547wt_905

PVC for rear 6.5"
http://cgi.ebay.com/Nissan-300ZX-Rear-S ... _803wt_905

I used the PVC brackets with not problem, im not sure if thats the same people i bought from, but i had to dremel the bracket to get a snug fit on mine, and they told me if i messed them up they would send me new ones. AND LASTLY, on the rears, the bracket will attach to the original speaker box, you dont need to remove it like in the front, but you will need shallow mount speakers and buy a spacer, or fabricate one. i think i made mine from like a 1.75" inch thick piece of wood and cut in a ring plus a little dremeling.... just buy a dremel if you dont have, they are so useful on this car....anyways...6.5 all the way around sounds nice....good luck and sorry for being long winded, i just want you not to suffer like i did with my stereo install.

[Ace2cool]

^^You, sir, are a SAINT tonight in my eyes. I haven't found 6.5" adapter plates for anything under $50 each.

[zain1003]

About the doors...they are tricky. you have several screws to remove from the door on the inside and one from the OUTSIDE from the circle behind where the glass rolls up at....there are also numerous clamps on the door panel. I figured it out when i removed my bose system and replaced with Kenwood. For ease of use, here is how to get to the speakers....mind you, the rears are an absolute b**** to get to....you have to remove all of the rear panels to remove the shock tower covers....so if you need new rear shocks, go ahead and do them at the same time. Here is a link to show how to do it all. Just scroll down to stereo installation on his z32 1992 tab. This guy outlined everything in detail, he is a god in my eyes.

http://www.twinturbo.info/

BTW if you have a four seater, you will need to remove the seats and panels beside them to get the last screw by the shock tower for the rear ones if you are going to do them. Also the stock speakers were quite small, so if you have the Bose system and you want to upgrade to 6.5 in the front you will need OEM brackets or PVC ones... Also, the rear took like 4X6" stock, so, youll need brackets for them as well if you want to do a standard 6.5" all the way around.

Stock ones, that only go to 5.25" and EXPENSIVE
http://www.z1motorsports.com/product_in ... ts_id=3875

Stock rear



http://www.z1motorsports.com/product_in ... ts_id=3838

PVC for front to 6.5"
http://cgi.ebay.com/Nissan-300ZX-Front- ... _547wt_905

PVC for rear 6.5"
http://cgi.ebay.com/Nissan-300ZX-Rear-S ... _803wt_905

I used the PVC brackets with not problem, im not sure if thats the same people i bought from, but i had to dremel the bracket to get a snug fit on mine, and they told me if i messed them up they would send me new ones. AND LASTLY, on the rears, the bracket will attach to the original speaker box, you dont need to remove it like in the front, but you will need shallow mount speakers and buy a spacer, or fabricate one. i think i made mine from like a 1.75" inch thick piece of wood and cut in a ring plus a little dremeling.... just buy a dremel if you dont have, they are so useful on this car....anyways...6.5 all the way around sounds nice....good luck and sorry for being long winded, i just want you not to suffer like i did with my stereo install.

Ouch sounds like quite a project. you were a huge help though thanks a lot i didnt even know half of that stuff =P. i think ill wait till it gets a bit warmer before i embark on this journey, but ill be sure to post a pic or two and let you know how it went. Thanks again for the direction!

[dantesdoom]

Ace:
Yeah i found those on ebay and just took a gamble on them. I wont say they are perfect as you might have to dremel the front ones to get a good fit. (I shaved them down a bit and put a fine line of a silicon sealant where it touched the door to prevent rattle, and i think i drilled one more hole and attached with a sheet metal screw...but then again I OCD over my Z.) Really my only complaint was that because the front had to fill such a large hole and it was PVC, it was not as sturdy as the metal OEM ones. On the other hand, the rear ones just replace the top of the stock boxes using the original screws, very little or no modification needed. Thats mainly because they had been making the rear ones for a while and when i got the front ones they were experimenting, in fact i sent them feed back on how i modified them so they might have made it fit a bit better, but at least it was a hair too big instead of a hair to small.

Zain:
Its not really HARD, just time consuming, and you have to keep your wits about you or you'll break a piece of your trim, but if you have someone to help you i would suggest getting them. I'm not sure about time, when i did mine i removed all the old system and ran new wire, new speakers, and head unit so in the future it would be easier to change, and i think it took me 2.5 days to get it to my liking. So for just the speakers i would probably set aside a friday and maybe the following saturday that way if things dont go as planned you can get it finished the next day or so, so your Z isnt stripped down and out of commission.

[dan4010]

"Well this has been happening for a couple months so i decided it would be worth my while to see what the nico community has to say about it. my 90 n/a 5spd has been running well except for a couple things.

1. around 1300-1900 rpm in any gear, the car SOMETIMES feels a little jumpy. what i mean is that the rpms go up and down +-100 about 4 times per second so its very quick. this gives me the same feeling as when a car is about to stall. during these rpm ranges, my accelerator feels spongy, as in it feels less responsive compared to normally and i dont get the adequate acceleration out of it. i this issue happens more often when its really COLD outside, or if i drive the car before the engine has warmed up (i rarely ever do that anymore)"

Zain1003,

Did you ever figure this issue out? I seem to be having a similar if not the same problem. Mine doesn't seem to depend on the engine being warm or cold though.

Thanks.

[zain1003]

"Well this has been happening for a couple months so i decided it would be worth my while to see what the nico community has to say about it. my 90 n/a 5spd has been running well except for a couple things.

1. around 1300-1900 rpm in any gear, the car SOMETIMES feels a little jumpy. what i mean is that the rpms go up and down +-100 about 4 times per second so its very quick. this gives me the same feeling as when a car is about to stall. during these rpm ranges, my accelerator feels spongy, as in it feels less responsive compared to normally and i dont get the adequate acceleration out of it. i this issue happens more often when its really COLD outside, or if i drive the car before the engine has warmed up (i rarely ever do that anymore)"

Zain1003,

Did you ever figure this issue out? I seem to be having a similar if not the same problem. Mine doesn't seem to depend on the engine being warm or cold though.

Thanks.

I sort of figured it out, b/c mine isnt that bad anymore but still there a little bit. first thing i would suggest is a tune up, and replace all your spark plugs. if that doesnt work, grab some "seafoam" fuel system cleaner from an auto store and pour half the bottle in your oil like 100 miles before an oil change, and pour the rest into your gas. when you pour it in your gas youll get massive amounts of white smoke out the exhaust, thats just the carbon getting cleaned out. rev it up in an open parking lot and get all that crap out. if this doesnt take care of the issue, its probably not fuel related and chances are its a bit more serious. one of your cylinders may be misfiring. i think one of mine might be but its not severe. also, i havent done the seafoam yet but did get a tune up and new spark plugs. once i get around to the seafoam i'll let you know what happenes with it. good luck though, that problem sure is annoying.

[zain1003]

oh also make sure your hoses dont have holes and that they are fastened completely and not loose.

[dan4010]

thanks. Im gonna do a 60K service on this jdm soon and will probably do some of that stuff too, maybe new coils, etc. hopefully that will do the trick. also thinking maybe its the TPS.