I was researching a bit based on my cars symptoms which are performance related more than anything, and I discovered I might have an issue with my Intake air temp sensor or coolant sensor...

the symptom being that when the car is cold it performs flawlessly with no hesitation at all. However, when the car reaches normal operating temperature when I punch it from a stop it just kinda boggs until the RPMs reach about the 3200-3500 range then picks up.

Any second opinions before i start replacing sensors?
btw no codes.

 

The IAT sensor is used for diagnostics only. It will not change the drivability. The coolant temp sensor on the other hand could. Its the 2 wire sensor on the log, its usually blue. Get a multi meter and test it out.

 

I think its the CTS.

 

My coolant temp sensor went about 8 years ago. I had zero driveability problems, but threw a DTC 13. New sensor was about $30 from the dealer and I had to buy a deep walled 19mm socket to do the job. Was a piece of cake to change.

 

there should be a code for that sensor.
when mine went the car ran horribly and died many times during slowing down or when at a stop.
its an easy fix and its cheap.
I got mine from O'Reily's for about $20.
also what you are describing could be need for new spark plugs and a knock sensor.

 

I removed the intake piping and used a couple of 19mm wrenches. I didn't feel there was enough room to go top down

 

hello first time user.i have a 04 maxima with a 3.5engine automatic. my problem is a no start condition with no codes i replace all three sensor,for it to run i have to disconetc bnk 1 cam sensor wiring check ok cam shalf ok ecm run fine in a difrent car....i need help thanks ,,,,

 

try in the 6th gen section. this is the 4th gen section which covers from 95-99

 

changed the KS about 6k miles ago
and plugs were changed about 20k when i got my coil packs replaced. and plugs wouldnt change drivabillity based on tempature

one thing i wanted to mention..(my brothers and i all drive maximas 95,96 and 98) my seems to warm up and cool down faster based on temp coolant gauge in the car?

...the CTS can also start to g o without throwing a code as well...much like most of the other sensors..

Ill prob replace it when i get back from hunting for the week...but can someone take a picture of where the sensor is located? i though it was near the left front part of the engine on of the lines coming from the radiator but i just wanted to double check

 

and if anyone else has a second opinion of what this might be.
feel free to add

 

 

Thanks! I was right about where i thought it was then...

 

I want to test my coolant temp sensor. What should the specs be, i have the sensor out of the engine so, would the temp of the air matter? thanks

 

so this i not a coolant temp sensor issue as i thought...i had it changed out and symptoms are still present. I am now thinking either MAF or a leak somewhere in my intake manifold, but a hairline crack that only opens when warm. any ways to test that theory?

 

granted im still a noob, but my gut is saying this is some kind of sensor issue (i know we talked about this before)

how long after its warm does the car begin to bog? how long after the needle is sitting in the middle?

 

Hmm interesting, I have noticed something similar lately.

I normally baby the car completely until the temperature gauge is in the center and then wait some, but still even babying it, no more than 2-2.5K rpm and no more than 1/8th throttle, it still feels much more torquey when cold than when fully warm. At around 2.8K I feel it really start to pick up and by 3.3Kish it really takes off.

But when cold it feels like it has a lot more low end power.


Also my car has trouble starting when warm. Does yours?

Maybe we have a similar issue.

 

It usually only take about 5 minutes for it to begin to bog after being started. which is usually when the needle is in the middle...im absolutely stumped...

no warm cranking issues btw

 

How much coolant came out for you guys during the swap? I'm going to be doing this tomorrow I think (had the sensor sitting around for a week) and I need to know if I should go buy some extra coolant.

 

not much at all

 

yea its very little. just make sure your car hasnt been driven for a couple of hours before you pull it.

 

Aight. And all you guys removed was the snorkle/intake?

 

lol I just changed it. Piece of cake.

I'm gona go for a 30 mile drive and see if it helped my symptoms at all.

 

back to my issue now....

i might try swapping out my MAF with one of my brothers MAFs and see if i notice a change

 

I have a similar issue as you and that's why I bought a ECTS. I just took a drive and it seemed the same (my issue is very faint) but my CEL is off for another issue (after clearing it and driving around).

Try grounding your MAF bro. The black wire. And try cleaning it with MAF cleaner made by CRC (Autozone).

 

did it seem to fix your issue?
how do i go about grounding the MAF?
just take an 8 or 4 gauge speaker wire and ground to the body?

and ive already cleaned it with CRC ...it helped a little bit but problem is still there

 

Yes. The black wire...splice into it and ground that wire.

I changed my engine coolant temperature sensor and I was able to get the car inspected just fine. Who knows...maybe the code is fixed now. Drove 50 miles and there isn't even a pending code (I had a P0171 - Lean Bank 1 code that I've replaced like 40 things for to try and fix and this finally did it - I hope).

 

well i grounded my maf...didnt help...so i think next week or something im gonna swap MAFs with one of the other 3 maximas in my driveway and see if that does anything.

the ECTS was a piece of cake to do...took me about 15 mins...and 10 of those were trying to find the wrench i needed :-p

 

Yep. Very easy. I did it last night in the drizzle and was still dry when done lol. I'm just happy that I passed my inspection. I've been expired for 2 months almost.

 

well i just changed my MAF and no difference at all

im thinking that maybe my cat converter is clogged?

 

Are you burning any oil or running rich? Normally that will cause catalytic converter problems.

I once had a car with clogged cats and my high end performance was miserable.

 

having an aftermarket y pipe wouldnt cause my to run rich would it?

when the car is running in "open loop" (warming up) it tends to be a bit peppier
i have an OBD2 CAN tool and it said my emissions were high

 

any other input is welcome

 

ttt

 

I also have this problem, and might try to do somethings that you all were talking about, but I may have to wait on the MAF, because I dont have much money to spend anymore.

 

to give you an idea of how much of a difference im talking about...im an auto...when i just start up my car i can chirp going into 2nd...and when its warmed up...i can barely chirp from a stop