rmdl51

iTrader: (4)

There's my point, that's why I don't want to argue anymore, unfortunately I'm not an expert on the matter and they claim to have done their job, I know maybe after fixing one problem anoher one pop-up right? but there is where I blame the mechanic, how come if TPS, IACV have problems he can't find out? well I just get a bad mood if I start talking about them, let's get back to subject...

what do you mean by charge voltage? at the main battery terminals? 12.8v with the car off

Wiking

Sounds healthy. Start the engine and measure while idling, also pull rpms up to 3k. Should be 13.8-14.7V. In some cases alternator drops intermittently off, this may cause voltage---> TCU problems. Install gauge to cig lighter to keep voltage measurement visible while driving. Check my alt page23.

Mech has to be able to check TPS and IACV. Dont just blame yourself; once upon a time I could do less than you; Maxima is kinda high as first learning step so seek hlp. Find a place where there is a willing mech who can check those while u stand by. I dont really know, but chances are that the tranny is problematic because of bad TPS or oxidized connector(s).

Still, check the other issues as said above.

-----------------------------------
edit:
Yes, 1st measurement at battery. 2nd measurement at TCU [PITA]. This b/c healthy batt voltage wont make TCU happy ... only healthy voltage at TCU is sufficient. Oxidated connectors on the trip to TCU may drop the voltage too much.

Note that TCU has two supply voltages = two fuses. Check.

rmdl51

iTrader: (4)

Thanks! unfortunately my DMM is at home and I'm at work right now, so I'll check that on the evening, meanwhile I'll check the voltage on the digital meter from the stereo at lunch time.

One more thing they mention, the electrician told the mechanic I have too much electrical equipment for my alternator, he said I need a High Output alt or I will have electrical issues all around the car, and Indeed I have two amps and a box with 2-10" subs but according to the measurements I make when I install the audio system my alt was supposed to be ok, I'll check the voltages to be sure Alt is ok.

measures on TCU should be with the car on?

Wiking

Good story.

However, your alt can push 90Amps.
90Amps x 12Volts = 1080Watts. I guess lamps, fans etc may eat 300W ... leaving 700W in reserve. How much does your sound equipment(s) take?

Alternator and/or supply wiring up to TCU can be faulty... your 12.8V at batt (engine off) sounds ok.

Pull/inspect/clean connectors at batt, AND at alt, see p.23 ... this beast did not deliver:

rmdl51

iTrader: (4)

total power on sound system 1100w RMS

mikekantor

iTrader: (5)

Peak power probably? 2nd battey might be an option if you are having serius electrical problems.

LvR

Nope - a 2nd battery in a system with inadequate alternator is a recipe to delay the onset of exactly the same problem - thats all.

BenStoked

iTrader: (7)

if the problem is the alternator, it can only keep up so much power. adding a battery without upping the alty will only drain the batterIES before the alty is forced to try to keep up (and fail to do so, causing .... possible alty failure, )

Wiking

If add on wiring direct from batt is ok, u may survive with that as that drain most probably is not contiguous. I guess police will ensure that... BUT. Alt and all wiring has to be in good condition.

Anyways in this case its good to know what TCU actually receives. Build your test wirings: Take 2 wires, solder to female connector, lenght maybe 2feet. Find a way to pluck the other ends into mentioned TCU connector pins permanently. Now you have a setup to attach multimeter, using a male connector, whenever you want to know wassup in TCU.

rmdl51

iTrader: (4)

Well I've learned about car audio the hard way too (I got ripped off) so I install my stuff by myself (with the help of another forum) and run all wiring and amp/speakers locations and make sure everything was safe and appropiate according to my knowledge.

Nope, not peak, RMS, if you wanna cofirm, my equipment is 2-10" Kicker CV-R ampr by Hifonics BXI606D setup at 600w mono at 1ohm , 6.5" comps Phoenix gold RSDs & Pionner 6x9" revs amped by Kicker KX650.4 this is 4x125w at 4ohm, total= 1100w RMS.

I agree that a second battery won't help relieve the ALT, I currently have an Optima Yellowtop which keep up pretty good. I was told I will need to upgrade ALT only if I wanna go over 2000w RMS, however I never confirmed if this was true or not.

well that was for audio equipment,

the voltmeter on the stereo shows 13.7 when I rev the car up to 3k RPM but then without reving it was on 13.4 so it doesn't go up much. is that ok?

BTW, TPS shows a lot of oxidation/rust try to clean it but I still have inconsistent readings on top and middle pins, I want to take it out but I couldn't, screws are incredible tight, I'm gonna try to buy some tool to help remove those

mikekantor

iTrader: (5)

What I meant by 'peak' is the actual usage. The equipment is rated for those amounts, but most of the time the actual consumption is far below.

Wiking

Voltage at batt has to be 13.8V minimum. At TCU 13.5V minimum. Read again the mentioned pages and clean all connectors, fusible links...

TPS Note: TWO connectors.

You are measuring (?) only the blk one = zero position sw. That is ON/OFF depending whether throttle is turned or not.

Measure the VOLTAGE at TCU as described; that verifies the potentiometer. Go back to page6 and read again.

budvoss

I read this whole thread and i must say, there are some very informative people here. I did a search on google for high rpm shift points on a maxima . this site came up.

I had tried every thing on my maxima to get it to shift at low rpm's. Im an old timer I want comfort not hard neck jerking shifts. I changed drop down resistors to the trans shift computer. Never would i have dreamed that the problem would have been the TPS switch. Any ways after reading this thread today i removed the wires from the TPS and found them a little corroded. I cleaned them up and the car now shifts like new.
thanks all

rmdl51

iTrader: (4)

Ok, I believe my TPS was bad, I just bought one and replaced and the acceleration is much better now, however I feel no difference on the shifting points when I use the mode switch... I think it needs adjustment but I don't know how to do this actually

Besides, I noticed that the inhinitor switch is not working! I can turn the car on while on D, 2, 1 anywhere the selector is the car will turn on, could you tell me where is this switch located please? I need to replace it ASAP!

haven't had time to check the voltages on the TCU, that will be my next move, but I really need to replace the inhibitor switch! I don't like that the car can be turn on in D and besides that must be why the self diagnost is not running!

Wiking

TPS: hopefully the zero pos is now adjusted?

Under air filter box is the mode resistor, check out.

For inhibitor sw adj, located at tranny cable end, see manual page AT-182. If I were you, I'd read the whole opus through at least twice (works also as a sleeping 'pill').

sonicii

Huh?? That is the dropping resistor which is in circuit with the line pressure solenoid, it has nothing to do with the mode switch. Disconnecting the dropping resistor will cause your transmission to run at full line pressure all the time, causing quite hard shifts, but it won't affect the shift points. Running at full line pressure all the time can also cause cracked transmission casings, so it isn't recommended.

The mode switch is just an input on the TCU which tells it to change the shift points. It will only be noticable at medium throttle, at light throttle you probably won't notice the difference, and at full throttle it will shift at the same RPM.

sonicii

The inhibitor switch will certianly stop the diag working, but you mentioned earlier that it was working ok and you could only start the engine in P or N??

As wiking said, the inhibitor switch is on the Transmission, where the shifter cable connects.

rmdl51

iTrader: (4)

What it the whole opus?

inhibitor sw is where the shiftter cable connects? so, can it be reach from inside of the car?

I know is very stupid but I assume (very bad from my part) that inhibitor switch was working, because it was just a day before mechanic took the car, I was even scared that the car didn't start, then a minute later I realize that the car was on R instead of P, so it didn't turn on, but yesterday when trying to run the self diagnose I just want to try it and I put it on D and turns on, I put it on 2 and it turns on, could it be that the switch is just disconnected?

Wiking

eh what did I write did I? The drop down R hit me in the head - the issue is just like sonicii states...

The inhib sw is attached to tranny. I'd be interested to see how one could reach it from inside ... now me stupido should not be laughing but to myself...

Right, check that the connectors are closed. Take the intake tube out to see better.

Yes, do read the whole opus ... reading seldom hurts. There are also long lists for problem solving, cant hurt.

Btw. FSM states that: "Hard closed throttle position switch: It is not used in engine control but for on-board diagnostics system" EF&EC p.12

rmdl51

iTrader: (4)

I really appreciate every word everyone types here to help me! I really do

but no offense man, I've read your post 4 times and can't fully understand it, maybe I'm sleepy, maybe I need glasses or a reading class..

I ask if the inhib sw can be reach from the inside because I have no idea where it is, and since it's connected to the shifter cable I tought could be close to the shifter selector, now with the "detail" provided to take out intake tube makes a better reference...

so the switch is under the intake tube? I'll take a look but still have no idea how it looks like, the FSM gives a draft pict which is hard to make a reference for my poor knoledge.

BTW last sentence:
(FSM states that: "Hard closed throttle position switch: It is not used in engine control but for on-board diagnostics system" EF&EC p.12)

I have no idea what do that means,

I know is hard to help someone who don't understand the basic terms on mechanical matter I really do (i'm a computer tech and is hard for me to explain basic terms to people who don't know anything about computers) so I hope you don't mind if you have to explain this like to a little kid who's learning to do basic math operations

I finally got the FSM and I might be able to read the references you been given to me, but some of the terms they use I still don't understand it, but as you suggest I'll read more and try to understand as much as possible.

Ones last thing, I just connect the TPS without any adjusments and then find on the FSM the instructions to adjust it but I don't understand the last parts of it. I'll copy here the instructions when I get home and read the FSM again but it says something about setting idle switch at -+250RPM which I don't know how to do.

Greeny

iTrader: (43)

rmdl51, Wiking is posting from across the pond (Europe), and is translating his words into another lauguage, so be patient with him.

I still have a hard time understanding his words.

Wiking

No, I dont drink... but tea plus instant coffee.

Above, I did quote the FSM word by word. FSM is also written beyond the pond, Confuzean katakana should I say. That is why we both do not understand it...

Yes please be patient. I am an patient - and even my wife doesn't understand me. Should I send her over? Oh boy.

NOw then, the wire - it has two ends. One end is stuck in the stick, the other clicked into the tranny. Tranny end has the gear selector/inhibit SWITCH... To find it, hood is firs opened.

You should also check all the other connectors that theyre connected. While there, open/measure sensor/coil resistances from the pins described at http://www.cardomain.com/ride/748507/15

And please, do give input on the very sentences that cannot be decoded - I do want to correct em ... one cannot insult me, Ive had it all ... because I am like this, small tin hat with headache.

Wiking

The inhibitor sw drawing is seen at AT-182.

Note that the FSM constantly jumps between VE / VG engines, trannys... This page is just for the VG / RE4F02A

rmdl51

iTrader: (4)

Sorry about that man! didn't mean to be rude or anything , I just got a little desperate to myself because I want to understand every effort you make to help me, but like a wise teacher once told me "don't try to run when you're learning to walk".

BTW! I didn't know Wiking location, Thanks to clear that for me Grenny.

well back to subject...

I have a lot of things to measure when I get home today, ok let's say the inhibitor switch is bad, is it easy to replace? or I need to get under the car and remove stuff and all that? (I'm looking to do it myself if it's easy)

Also the Year on my FSM says 1990 so that year was only VG engines right? but I'm not sure if even this FSM talks about the VE

sonicii

The inhibitor switch is on the transmission itself, close to where the shifter cable attaches to the transmission, which means it is at the back of the transmission. There could be an electrical cable disconnected, but I suspect if a cable were disconnected you would not be able to start the car at all! Perhaps the mechanics disconnected it then used a shorting clip to bypass the switch, then forgot to reconnect it?

The hard closed throttle switch is part of the TPS. as wiking had said earlier, there are 2 parts to the TPS unit, one part is a potentiometer which the TCU uses to determine the throttle position, and the other part contains 2 switches, one that closes when the throttle is fully closed, and the other that closes when the throttle is about 3/4 open.

The close position switch is apparently only used for the diagnostics. Although I had earlier assumed it was used for the fuel cut feature in the ECU, and to disable the transmission lockup clutch..

To adjust the TPS, you need a DMM on the throttle closed switch section, adjust the TPS position so the switch is closed when the throttle is closed, and then the switch opens as soon as the throttle is opened a little.

Hope this makes sense??

CapedCadaver

iTrader: (8)

translate as in in his head or w/ an online translator. i'd assume the first, as he's got some pretty cool sayings like "blondie bubbles". Ain't that right, Wiking?


also this is what you look for I have one if you need one, but if the car DOES start in gear, the problem seems to lie elsewhere. have you tried starting in L? try that and see what happens. D could potentially slide back to N, and so could R to P or N... 2 seems unlikely to start in even if ALL shifter bushings are gone, and L is impossible to do no matter how bad the shifter is.

rmdl51

iTrader: (4)

Ok, now I think I can finally start to understand, please correct me if I'm wrong...

you are telling me to disconnect the throttle closed switch (the top one right? the one wiking refer as throttle zero position?) and put my DMM there.

Then turn the car on and measure on the connector to show some reading on ohms (what reading I should be getting?) as soon as I step on the gas pedal?

FSM states as follows for TPS adjustment:
1-Install throttle sensor body in throttle chamber. Do not tighten bolts. Leave bolts loose.
2-Connect throttle sensor and iddle switch harness connector
3-Start engine and warm it up sufficiently.
4-Turn diagnostic selector on ECU fully clockwise
5-Disconnect idle switch harness connector.
6-Check iddle switch off -> on speed with circuit tester, closing throttle valve manually.
Idle switch off -> on speed: A/T Engine speed (idle speed in N position + 250 +- 150 rpm
7-If NG set idle switch off->on speed to the specified value by turning throttle sensor body, connect circuit tester and find out off->on point.
8 tighten throttle sensor bolts carefully after setting so that TS does not move.

Could somebody clear from step 6 to 7 for me please! "closing throttle valve manually" how do I do that? with the DMM on top and bottom pins what should I get? what do they mean with 250+-150rpm??? I should depress the gas pedal in N to achieve 250rpm? how so if lower is about 1100rpm when in N, I will really appreciate if somebody could tell me more details on how to do #7 when it says if NG set idle switch speed to the specified value? where do I set that value?

I do now understand that I should read a number on ohms and I have to set that number somewhere else but I'm lost where...

Wiking

My tranny-slator is under a tin hat with horns - its unline translator?

Forget the Confuzean beyond the Pacific pond - try now Atlantic flavor:

.

Multimeter Beginners Lesson 1 (testing conductance).

1. Turn it ON - its battery has to be healthy.
2. Turn Selector Ohms Scale [any].
3. Check that Probes are correctly installed - How: read your manual.
4. Cross the probes by touching. Read display: Now you have a reading that a connected switch makes ... variations due to dirt may exist
5. 'Disconnect' your probes ... Read display: Now you have a reading that a disconnected switch makes = NO conductance.

.

Testing the TPS Zero Position Switch:

0. Open the hood.
a. Engine oFF, everything peacefully resting...
b. Disconnect TPS Switch connector.
c. Measure sw pins --->For Multimeter Reading refer to Lesson point (4.) above.
d. Keep measurement on-going. Here clips will help.
e. Turn throttle by hand. Switch should now open - Reading should look like at Lesson point (5.)

Adjust the TPS until you are there: Loosen TPS attachment screws, tighten, retest... return to Lesson point (1.)

.

Just a Comment, dont get lost in here: Is the TPS switch used, who knows. The claim in FSM is incomprehensible. Maybe its true, maybe not. This name some japanese blondie invented, is funny: "Hard closed throttle position switch" ... from this one may assume there somewhere behind Pacific blondieworld exists also Soft Closed Switches --->tell me what are they?

sonicii

Sounds like this section of the FSM was written in japalish. No need to start the car or mess with the diag screw when adjusting the TPS, just remove the connector on the body of the TPS itself, loosen the mounting screws, put your DMM probes on the closed position switch pins. (I think this is the center and bottom pins). Turn the TPS so the switch just closes, check that the switch opens when you turn the throttle a little, tighten the screws, double check the TPS again with the DMM, reattach the connector!

sonicii

it does actually mention a 'soft closed throttle switch', according to the FSM it uses the potentimeter to determine the 'soft closed' position??? Hardly a 'switch', seems like the just select a name to cause the maximum possible confusion!

CapedCadaver

iTrader: (8)

it wants the engine speed to be 250rpm over idle, give or take 150rpm. ie, between 100rpm and 400rpm over idle.

BenStoked

iTrader: (7)

the "specified value" should be stated in somewhere in the section of the fsm. i think those instructions arent always made specifically for the section they are listed for, but rather the pictures are changed and some words here and there to make it fit.
(ie. they have a generic FSM and they modify that one to fit the model they are "writing" about.)

rmdl51

iTrader: (4)

And where do I set it between 100-400rpm over the idle? do this means that the throttle should open at 100-400rpm over the idle? that's the ideal adjustment according the FSM?

if the answers to the last two questions are yes, then It's the same procedure Wiking and sonicii explain I guess and after the adjustment after the car is turned on I should check maybe that throttle opens at 250+-150rpm over the idle. am I right?

If I'm right then finally I'm putting all the pieces togheter, after all it might look easy but being unfamiliar with all the terms and masurements makes it a little hard for me.

Ok I'm going to try to adjust right know and I'll let you know, unfortunately daylight is gone and hate lamps but I gotta do it now or until saturday, better start now

I want to solve my acceleration problem first, then, inhibitor switch is next

CapedCadaver

iTrader: (8)

jam tiny slips of paper under the bump stop on the throttle body. add layers until desired rpm is attained. i used a smashed-and-bashed dime to hold mine at 2000rpm.

rmdl51

iTrader: (4)

why did you hold yours at 2000rpm? idle is supposed to be what? 1100-1200rpm at P or N, and while on D is 800RPM right?

mine idles 1200at P and 550-600 at D

CapedCadaver

iTrader: (8)

my bad for confusing you. 2000rpm was to test my 02 sensor.

sonicii

It sounds like the FSM is saying that the throttle closed switch should open when the throttle is opened far enough to increse RPM 250rpm above idle

rmdl51

iTrader: (4)

Ok guys, I finished my failure attempt to adjust the TPS, I did as you told me and on the DMM I got no readings on the top and middle pins, the potentiometer is ok, starts on 1.768 Kohms and tops at 4.856 Kohms but the zero position switch gives me no reading on any pins and this is the brand new TPS, I also tried my old TPS and it shows nothing.

I put a dime as one of you guys suggested on the body throttle stop bump and then tigthen the bolts of the TPS since I can't get any reading I did that, but I see no improvements at all! the shaking is pretty bad and the take off takes forever to lift the needle to 30-35mph, ok not forever like before but still I feel no power when I step on the gas pedal.

I tried to shot a video running the car up to 60MPH so you can see the shifting points but it's too shaky (i'm a noob taking videos too) but well I took some pictures about the inhibitor switch and damn I can't find where can it be disconnected!



There is the worm hose that expands and contracts when I more the selector, but the FSM says disconnect it and put the circuit tester on pins 1 & 3, and I wonder which connector!

Wiking

If there is any message [?] in the FSM, its prerequisite for the zero sw to work before a test goes through... Goal for its adjustment: The system needs zero position info.

VGE Potentiometer is from 1 - to 9Koms. VG30DE is from 0.5 to 5 Kohms
Is there any difference in ECU's, dunno.

S3.
Again, check again, some new picks for ya @ http://www.cardomain.com/ride/748507/15

internetautomar

iTrader: (30)

walt - it's VE30DE not VG30DE :