1990 300zx na Hesitation

[nightops]

I've pretty much come to the conclusion that I'm going to sell my car. There's 1,000 things I could check but I don't have time to do it. There's just too many negatives that I have to accept with these cars. This being my second one, I know a lot about the negatives. Yea it's a cool a** car but IMO not worth it right now for me. Maybe when I have more time and money I will upgrade to a twin turbo as my weekend car!

yep these are definitely weekend cars or second cars unless you have changed everything on them, but at that point you can be a much newer 350z or G35 and have more reliability and power over the NA. The TT when properly modded is much more of a rush and delivers the pin you to your seat performance but I can't see beating on it daily especially in heavy city traffic. I think you have the right idea unless you've put a ton of money into the body and interior then i would just do a tt swap and you'd have a nice car if its done correctly.

[mada300zx]

I came across this video...http://www.youtube.com/watch?v=GhaW8j6RbJEmaybe this will help one of you.

[fowlladyZ]

the knightdale guys r the s*** dude

[zxFarside]

I may have to head over there and have them check my car out.

[mada300zx]

So has anyone gone through the checklist for this hesitation problem yet?

[Ace2cool]

I cleaned my throttle bodies, TPS, and temperature sensor and I definitely felt a noticable difference. I think the TB's had the biggest effect. It even starts up easier now. My TPS was greeeeennnn. so was my temp sensor.

My idle has been odd lately, so I'm most likely going to address the IACV plug and valve itself next. I'll keep you updated.

[zxFarside]

So has anyone gone through the checklist for this hesitation problem yet?

I'm going to run through it tomorrow given the weather isn't to bad. I'll post my findings.

[mada300zx]

I'm looking forward to it! I wish I had time to do it. Going to work till 12 am then having school at 8am isn't really helping much. Not to mention I'm going to mardi gras tomorrow!!! I'll get back with you guys later. goodluck!!

[zxFarside]

I'm going to run through it tomorrow given the weather isn't to bad. I'll post my findings.

The weather was bad today. Rain rain rain. I'll get a write up done in the next few days.

[zxFarside]

OKAY.

So after a few hours of tinkering under the hood I cleaned most of the connectors listed in the link posted (TwinTurbo.net) I found that my coolant temperature connector was corroded to the point that there is really nothing left so that will have to be replaced.I also found that I had some vacuum hose that was disconnected so I fixed that up.

The car was running smoother.

Also I changed my plugs maybe a month or so ago and I finally look at the old plugs today and they are NGK BKR5EGP. Dunno much about plugs just that those arnt what the usual recommended plugs are.

Also Also, Next week I get my 1-Piece drive shaft and I'm going to do a full write up on the process.

[arcadia0]

Dont count out your trans. my 91na auto does the same thing but it was also shifting a little hard. Nrxt thing I knew drive 3 and od went out while driving under normal conditions. I dont know if the trans. was already going or if the hesitation caused extrea strain. Just saying heads up.

[fowlladyZ]

I think my problem was my auto trany, did a fluid change and its running soooo much better now

[zxFarside]

Thanks for the heads up. I think I will change my fluid and filter.

[zxFarside]

I think my problem was my auto trany, did a fluid change and its running soooo much better now

Do you get it flushed or just a drain and filter change?I have been reading up on some disaster stories from flushes.

[mada300zx]

Glad to see some of you guys figuring out the problem! I'm going to try to knock out a few things off the checklist tomorrow. I'll post my findings...

[zxFarside]

Good luck. I had fun cleaning up under the hood

I got a huge list of crap I'm doing in the next 5 days. Gotta install my drive shaft, smoke out my lights, install a hard-pipe kit, repaint my front fascia, and painting my wheels.

[cjrboy14]

i have a 92 n/a 5speed that does this around 2500-3000rpm or around 60mph i have to do over 60 or under to keep it from hesitating like that

[mada300zx]

Well so far I have... Clean the TPS (Throttle Position Sensor) Clean the air filter Clean the injectors Change the spark plugs Change the fuel filter Clean the Throttle Bodies Clean the Mass Airflow Sensor (MAS) connector Change/add coolant

I still have the problem! I am starting to think that it is because I have a 1990. There are a few more things I need to do though. Has anyone had trouble disconnecting the CAS? I feel like I'm going to rip it off! I also need to check the detonation sensor.

[Ace2cool]

I also need to check the detonation sensor.

Um, yeah. Good luck with that one. You need to remove the upper and lower plenum in order to even see the damned thing. I wouldn't worry about that one unless you're doing something significant, like injectors.

I haven't done anything else with mine, mainly because it's getting paint. I'll see what else I haven't done.

What octane gas is everyone running? Just curious, because mine seems to respond a LOT better when i use octane booster, since California gas blows donkey d!ck and the highest octane gas they have is 91.

[mada300zx]

What octane gas is everyone running? Just curious, because mine seems to respond a LOT better when i use octane booster, since California gas blows donkey d!ck and the highest octane gas they have is 91.

I'm running 93 octane. My problem seems to be getting worse now. WTF

[zxFarside]

My Z didnt start yesterday for a little. Scared the hell outa me.

I would look into the O2 sensor, then look to the injectors. Definitely look to the O2 sensor though, they really can mess your stuff up.

[mada300zx]

well I just had my injectors replaced so it can't be that. But I guess 02 sensors are a possibility! Damnit! That's one more thing I have to do now! FML

[mada300zx]

I forgot to mention. I have been noticing the past few days that when my car is cold, it never has this hesitation problem. Every morning it drives fine but when it starts to warm up, the hesitation is back! I'm not sure if that helps any but it is more information I wanted to share to see if I can narrow the problem down!

[zxFarside]

Mine happends when the car is cold and when it warms up it clears up lol

[z32pilot62]

when my car is cold, it never has this hesitation problem. Every morning it drives fine but when it starts to warm up, the hesitation is back!

Same here bro, 90 NA as well, Ive been through the whole list. Had an injector fail, fixed that, oxygen sensor fail (thanks injector), fixed that still hesitates but its not as horrible. I need to check my plugs and change my fuel filter, i get some serious let down at about 6k at wot but back it off the slightest and she comes right back so im guessing fpr or ff, cheapest parts get fixed first... Shes been like this since i got her and that was 10k ago, been fixing everything i can think of and it still does it so i feel your pain. After fixing the injector and o2 its idling so much better now but mine is like everyone else hesitates till 2.5k then takes off like a bat out of h*ll. Oh and to the guy saying transmission, i changed mine with a brand new one as well and the problem persists. Its all a matter of time until i track it down but im thinkin im gunna start doing some deletes/bypasses to get rid of potential problems.

http://s95014253.onlinehome.us/63104/197490.html

PRVR, and CC to start with... The rest of the stuff is being deleted/bypassed on my 2+2 this one can wait for someone else since its for sale anyway just want it to run good for the future owner.

[mada300zx]

Good luck to all! I found someone to buy my car for $7,000. So that's how I'm going to fix this hesitation problem!! lol.

[nightops]

7

Good luck to all! I found someone to buy my car for $7,000. So that's how I'm going to fix this hesitation problem!! lol.

wow 7k for an NA? the market is not as bad as i thought- g/l.

[z32pilot62]

I found someone to buy my car for $7,000.

D*mn bro! Find me a sucker next please!

[zxFarside]

Good luck to all! I found someone to buy my car for $7,000. So that's how I'm going to fix this hesitation problem!! lol.

Where do you live that people would buy a car for that price...

BTW those are some kickin' subs


Modified by zxFarside at 10:39 PM 2/15/2010

[mada300zx]

Where do you live that people would buy a car for that price...

BTW those are some kickin' subs

Modified by zxFarside at 10:39 PM 2/15/2010

I live in south Charlotte. Some kid wants the car really bad so he is buying it after his next paycheck. It's not what the cars worth, it's what its worth to YOU!

kickin subs????