Still haven't found my problem and my old posts are dead so I'm reposting

Symptoms: hard starting in cold weather and sometimes starting after a half hour of sitting, when I take off when the motor is still cold I get some surging/hesitating ( like Swaying back and forth) under 2000 rpm in any gear, almost completely vanishes when war but still there, it kinda turns into dead spots rather than swaying

I have tested
Tps. Could it still be bad though cuz I heard they can. Give these symptoms that vanish once warm
Maf. I swapped it for another one real quick from a 5.5 gen didn't notice much change
New plugs
New cts
No vac leaks
New plenum gasket
New fuel pump and good pressure
Performed moto vac to clean injectors and upper chambers


What symptoms would cause bad hesitation or like the vehicle swaying back and forth when cold but still slightly be there when warm? And only under 2000 rpm. If I accelerate hard I don't feel it if I cruise around town with the rpms above 2000 rpm its fine.

This is an automatic 2000 with 134000 kilometers. Would a bad maf cause hesitation under 2000 rpm? And worse when cold? I'm thinking what ever the problem is, its not bad when warm cuz the 02 sensor is kickin in and correcting it but when its warm the 02 sensor isn't functioning.... No cel either

 

If you have replaced the upper intake gasket, there is still the possibility that the plastic manifold is cracked. I have seen it happen. When it warms up it would swell together and mask the problem. Or it could be warped, doing the same thing.

Squirt some carb cleaner around the intake manifold the next time it is running cold. You may find the problem that way.

 

Hey thanks! The thing is... I did a smoke test on it when it was relativley cold and no leaks found... Thanks though

 

When I drive away in the morning it feels simular to stopping with warped rotors if that makes sense haha, once its warm, taking off from a stop feel like it has a distinctive "miss" at exaclty 1600 rpm, when cruising around town in that rpm range it feels like. A consistant miss or skipping, also I plugged my tps plugs and fired it up, no engine light came on, it seem normal but after about 20 seconds. It started bogging in idle when I would hold the rpms in that range but no where else. Sorry about my grammer and spelling I'm doing this off my phone and can't really see what I'm typing cuz the screen is to small

 

+1 on the upper intake gasket

 

Guys, I replaced the plenum gasket, performed a smoke test when it was cold.... There are no vaccuum leaks but thanks! Any other ideas???

 

Look into the iacv (idle air control valve) located on the bottom of the throttle body. Try pressing on the gas peddle and start the car and see if starts, if does then the iacv is bad. Pressing the gas peddle won't add fuel but allow air to go into the engine, when turning on the ignition in your car the iacv opens up to allow the engine to start. Repair soon because if this completely goes bad it could fry your ecu.

 

My idle is good though.... Never dies or shuts off, I've tryed pressing on the peddle it didn' if I let it run for 2 seconds then crank it, it fires right up.
t help but... If I turn my key on and let it prime then turn the key in the spring load portion of the ignition, right befor it starts to crank I hear my fp run, then kick it over and it fires right up
The iacv wouldnt cause the hesitation either because its bypassed once throttle is applied and I can hear the butterfly valves open and close with throttle applied so there not stuck or anything, but thanks

 

I have a similiar issue, did you ever figure this out?

 

nope..... havent figured it out... i have determined half of my problem is totally different though.... so now.... new grounds to search....YEPPY

the starting im not too sure about....
i know that if i turn my car to acc. allow my F.P prime... then slowly start turning the key .. right befor it kicks over.. i hear my fuel pump run.. i let it run for an extra 3 to 4 seconds, i canthen hear it being dumped back into my tank via return line... it kicks over on the second crank ... a perfect start!...

when it does struggle starting its kinda simular to my C.S.P.S (POS) or at least its the same kinda struggle i saw posted on a vid here .. it just started a bit faster than his.. but same struggling idle for the first second or two with a couple oil light flickers...

ive pretty much figured out how to start it properly so thats not my bother anymore...

but.. when my vehicle is cold and i take off at slow speeds and my rpms climb i notice that i get a hesitation right befor it shifts... which i thought was 1. vacuum leak 2. coils or plugs 3. fuel issue(also cuz of the starting) 4.maf 5.tps.... none of these were my issue... among other things ive checked....

i have narrowed it down to definatly be a trans issue now.. here are my updated symtoms that ive totally narrowed down.. if anyone can help... i would be amazed !!!!

hesitation when engines cold.. only at low speeds i notice it... its more pronounced in 1st and 2nd..

once warmed up the problem disappears... but my shifts are sloppy and i feel like i have a abnormal loss of torque... its not like its slipping, there is absolutley no flair.. its just when it shifts it takes a bit for the rpms to drop down as it engages into the next gear, then it kinda sticks and slowly advances up in rpm...

anything under half throttle with minimal load it has a nice normal kick shifting into any gear.. medium throttle and up with a decent load it just slops into next gear first the worst, 2nd better buts still there third it starts to dissapear and so on... when i mash on it it shifts better.. but i can still tell there is something... mashing on it off the line i feel like im driving a 4 banger ... cant spin my tires and it lags taking off... once it hits like 2500 rpm i can feel a increase in torque

i also notice that it feels like my car is shifting way to early.. it feels like its always in the wrong gear ratio for the engine speed ...

sometimes ... lets say... im sitiing at a red light and im going to turn left .. so the light goes green and i proceed to take off befor i finish the left turn right as im coming out of it i go to press a bit harder and it shifts right away making it really sloppy cuz its trying to increase in speed and the shifting is so lazy .... the shifts feels like for instance.. if you were driving a standard car and when to throw it into second and at the same time releasing the clutch you mash on the gas and you get that slow engaging... but with no flair ( i dont know if that is understandable :P)

if im cruising around town and i take my foot off the gas its got a sloppy go.. it seems delayed getting back into gear... and... sometimes it feels powerless for two seconds and upshifts and slowly takes off

i do notice cruising around i can almost feel a slight hesitation ... but it feels like attempt to shift... like its rolling into the gear... which gear , how or, why i dont know... there is no movement in the rpms.. its quite quick..

another thing(bare with me guys i know i should prob get this "book" published lol)

at highways speeds it seems to be alot more peppy.. but .. if im in overdrive and im just cruising at about 50 MPH and rpms are at about 1600 as soon as a give it a bit more throttle .. i can feel it almost... downshift i guess, the rpms will jump from 1650 to about 2000.. ok great im in my passing gear 3rd right? so i click overdrive off and bam! up to 3000rpm.... im pretty sure that my 2k max with an auto tranny is a 3 speed tranny with overdrive...... so.... if i was in overdrive and downshift... and then hit od off???? do you see anything wrong with that pic??? its like there is some extra gear there...

one thing i will add it makes it much better when im cruising under 50MPH with overdrive off each gear band feels more peppy... i know some would say well thats because your at higher rpms cuz its not shifting into od... not the case cuz it feels different in every gear ... same with my tcs... it makes a huge difference.... so know when im cruising in town i keep od and tcs off as soon as i hit an onramp and finished merging.... click the od button on...



a few questions if anyone can answer
1. when should a tc. lock up? i think it 40mph? correct or no?
2. when should my od engage? is there a certain speed befor it will allow it to shift into od? cuz if im cruising around going 20mph and i push od off.. i can feel it downshift .. isnt that a little early to be in such a high gear??? and power robbing!!!!!!

tomorrow im getting the a.t. flushed i heard good and bad things but... i know it should be benificial in my case 162,000kms (100,000miles im canadian) and previously done at 50k miles.. this thing was vigorusly maintained by an elderly couple... other than this problem lol i love my car!!!!!!
im guessing either
tc
solenoids
tcm
ive heard of the tsb for low pressure due to a clogged return line on the atf cooler which is why im getting it flushed

anyways any help would be appreciated !
thanks for reading my book!!!!!!! hahahahahahahaha

 

Hmmm. Torque converter perhaps???? I'd be leery of a trans flush especially in a higher mileage car. Might just put the trans over the edge........ I'd would check the tc, and also the fluid ( which I'm sure you already did). Keep us posted.

 

Yea that is kinda my guess too... i really hope it isnt... anyways i think i still might go ahead and do it since its not very high in kms and its been performed befor ... i really hope its not my tc!!!!

 

I just posted a new thread and i had the same problems changed the maf sensor and nothing and checked my oxygen sensor and did NOT have a check engine light , but one of my oxygen sensor was bad Bank sensor 2 red wire. I changed it and its a rocket no more hesitation. Maybe you could check your oxygen senors doesnt hurt to check and good luck.

 

I'm having a similar yet different problem and it all started about 2 weeks ago. The car starts up rough ONLY when it's cold, it slightly vibrates at idle. The car runs good when I give it gas all the way, crusing it however it struggle's and it sounds rough when it decreases the RPM like something is clogging the engine and it lags to shift at normal speeds. It also feels clogged when driving normal speeds, no missfire or anything though. No codes pop out or anything. Im gonna replace the MAF soon but something tells me that won't solve the problem. Any other suggestions?

 

...coil packs? Not sure though, weird no check engine light or anything.

 

Still havent determined my prob... i looked at my 02sensors with my odb2 seems to be in spec.... i wanna buy a new tps even though its checkin out with no dead spots... to me it feels like it could be it and it makes my trans disengage.and engage again...... i guess ill just throw one at it...... no

 

Something with the Manifold

 

ok so by reading your problem i just want to let you know that i have a 2002 6speed and i got the same problems of hesitation i have i would say 45% of the power and torque it should normally have i cant even chirp my tires takin off in first gear no matter how much i try thats how bad it is, i have new maf,new coils, new plugs,new knock sensor and no codes at all..i also want to know what else could it be

 

like what? manifold how...could u explain more? :scratch

 

clutch? being standard and all i would say you got and issue with your clutch? if you engage your clutch but only roll.. no throttle, and mash on it you cant spin your tires??? is that what your saying? then you can rule out your clutch....

 

I believe they were just post-whoring to get to 15. They had a series of vague comments in multiple threads all at once.

 

well what i was trying to say is that i have a 6speed and he has an auto and we got kinda the same problem so i wouldnt be the clutch then...no matter how hard i try i cant spin tires even from a dead stop like a burn out, before i use to chirp 1,2,3 but now not even 1 on take off no matter how hard i try because once i hit more than a little tap on throttle it kinda bogs n then starts climbin up the rpms slowly takin on speed

 

I think 2000 was the last year for the EGR valve and that little monster could upset timing and power if fouled. Check it to verify it is not clogged up. Also look at your ground wire to the transmission. Aaron the NWP spacer guy has a photo of the 2000 EGR on his how to PDF

 

If the VIAS isn't operating properly (broken actuator cup) It makes a huge difference in an AT car as far as low speed driving is concerned. Especially if it's in partially closed/open state.

 

ok... egr and vias....

egr- i acually took the cap off the egr and saw the valve had movement and was not stuck.... not too sure about the tube being cogged though.... wouldnt i get an ses light with a clogged egr valve??? i know that the egr valve opens closes at 1500-2000... i get some major hesitation esp. when cold which is why i took off the cap because they dont function when cold and i figured maybe my valve was stuck open..... nope ... i guess i will take a look at the tube to make sure it isnt clogged...... gay!!!! is there an easy way to inspect the tubing without taking off the manifold?

vias- i know it engages at 5000rpm on the 00-01's this true? if i leave it in first and floor it till it hits 5000 will i def notice the pitch change.. is it a cant miss it kinda sound??

these are really the only two areas i havent addressed..... i wish it was just my vias.... that will be the first check since simplest!

thanks guys!!!!!!!!!!!!!!!!!!!!!!!

 

does anyonne have a good write up with pics on the jb welding part of the vias ???? yes ive looked and cant seem to find anything with pics of whats actually being glued.... i have no probs taking it apart/ putting it together, i just wanna know what i weld because i see ithere should still be movement or something blabla bla! im super hands on.... u think ill just know when i see it should i just take it out and try and play with it? i think mine is stuck open cuz i have no low end power lol

 

http://www.vqpower.com/v2/articles.php?article_id=21

 

Yea i saw that one... it still confused me... but.. i took it all apart today its fine .. solid as a rock! i guess ill check out my egr but im 99% sure its fine since there was only i tiny tiny amount of oil residue in my vias... no carbon buold up or nething.... im goung.to run some seafoam through my intake.. clear it up a bit lol ... hopefully lol

 

Does the actuator open/close the VIAS when you rev it up? You should be able to see it move while working the throttle from under the hood.

 

sorry about my last post.. at work .. veryu busy haha.. thanks for posting that link bobpezz, i did see thaty one while searching... it for for some reason didnt make any sense to me... i took it apart on my lunch break and when i looked back at it, it all made sense.. i guess it was just one of those open her up and u'll understand... but thanks...

so i did open it up.. very solid and moved perectly fine.. put it back together (stripped the threading of the lower bolt closer to the throttle linkage!!! but put a longer 10mm bolt... with a shim.... in placement of all the soft sh**ty screws so i can easily access it again with my ratcheting box wrench :-)

that was what i did right after i put it back together.. warmed her up and yanked the throttle linkage and saw it move........ fml..... egr next...
again here is what ive done so far
plugs
fuel filter/ pump
plenum gasket/tb gasket
cleaned tb and somewhat cleaned iacv
pvc
air filter
maf
tps adjustments from .48 to .75
i did hook up my scanner and watch my tps and didnt see anything unusual.. but.. who knows... replacing after i check egr just to make sure since i have some slight shifting issues as well
fuel pressure tested
obv. now vias
smoke test to check for vac leaks
moto vac to clean out carbon buildup
new cts

i dunno... process of elimination....i guess......

 

tps was my issue.... i just put it in yesterday.. huge improvements.. it.had nothing to do with the the top plug on the tps it was the open closed circut (bottom plug) thats.why i didnt see it when i was testin resistance through out the.rpm range.. thanks everyone for the help... im a happy maxima owner... for now.. hopefully my problems dont come back!!

 

I have this Same exact issue im going to look into the TPS.