561rpm

First off sorry if im posting in the wrong section I've never used a forum before. So i have an 03 350z that i cant get any throttle response from. Gas pedal does nothing. I have 5v signal output at w.o.t. from the pedal sensor and i checked for continuity from the ecu pins to all 6 wires on the throttle body and it checked out fine. So pretty much my app is sending signal but its not getting back to the throttle body and the continuity test confirmed there are no shorts in the wiring. The app senor, throttle body, and ecm are all brand new and hasnt solved a thing. Could the ipdm be causing this? i did also change all the relays in the ipdm

dkmura

iTrader: (64)

Did you try to download any codes? Your Z has a sophisticated diagnostic center that'll tell you what threw your car into limp mode.

561rpm

The only codes that come up are for the app and throttle body. I did have a can com code but havent had it since i put the new ecu.

dkmura

iTrader: (64)

What codes are they? And what kind of app are you running? Also, why was a new ECM installed?

i8acobra

iTrader: (6)

APP = Accelerator Pedal Position sensor.

We need actual codes.

561rpm

Codes are p1122, p2122, p2127, p2138, p0223, p0123. Im using an autel maxidas. And ecu was changed because seeing that the ecu was recieving signal from the app but not sending to the throttle body I thought that was the problem

561rpm

Anyone?

dkmura

iTrader: (64)

The problem with that many codes is it could be anything from a defective component to a dinged connection to who knows what? Trying to get answers from behind a computer screen is haphazard at best. My only suggestion is to find a good Nissan technician with Z33 training and experience to diagnose it properly. Part of being an effective DIYer is knowing when to say when.

561rpm

Nissan dearler here will not touch it because its modified and tt. My question was simple could the ipdm cause this. I dont expect a diagnosis just some input. Wiring checks out fine and all components are new. I have signal to the ecu but not to the throttle body this is not a result of a faulty component. The only thing i can think of between the throttle body and ecu is the ipdm hence the question can the ipdm cause this.

Atreyu'z 350

Yeah. If it got wet, shorted out, or has corrosion.... Did this all start happening out of the blue?

561rpm

Yeah. It was woring fine and then just started acting up out of no where. I took apart the ipdm just now and there is some minor corrosion on some of the pins but none on the circuit. Im gonna order a new one and see what happens. Ill keep you guys posted.

Atreyu'z 350

Why don't you just try cleaning the corrosion off of the original one first and see if that works instead of buying a new one right away?...

i8acobra

iTrader: (6)

Clear the codes and see which ones come back at "key on, engine off".

561rpm

So i got the new ipdm and the bottom plug was extremely corroded. So corroded that it fell apart when i pulled it out and now i have no clue where the pins go. Can someone take a pic of the long plug on the bottom right of the ipdm detailed enough to see the location on the wiring?

zakmartin

Is there anything else you want to share about this issue? It seems like you're adding information that should have been posted in your first post with each new response. What I'm getting out of this is that you basically have a heavily modified engine that isn't playing nice.

561rpm

Yeah its a built de with a custom twin turbo setup (pair of gt35rs). I apologize didnt think the mods were related since ive been diagnosing the problen with stock ecu. Ive come to the conclusion that the ipdm is responsible for the issues ive been having due to the corrosion inside. But upon removing the ipdm one of the connectors broke and the pins came out. So now im faced with a new issue. I tried the fsm with no luck. I also got another plug for it with about 2 inches of the harness on it and I was going to just take out one pin at a time and match the colors putting the matching color from my harness in the connector 1 pin at a time but the color code is different on the connector plug that i got.. so i still have no clue where to put the pins.

zakmartin

I had a look through the FSM too. Wow. If you're going to be mating up parts that aren't year-specific for your car, the IPDM isn't the part I'd want to be attempting that on. Any chance you can get the right part for your specific year/model/trim? You can get a wiring diagram from Alldata but it's still going to be a pain to match up colors and pins between incompatible IPDMs. What would worry me the most is that a single mismatched wire can fry your ECU.

http://www.nicoclub.com/manuals/350Z/coupe/2003/pg.pdf

Cux350z

iTrader: (162)

Ok...so lets try a few more questions and things to do

What ECM are you running...stock ecu only, utec, haltech?
Take your ECU connector off. Rotate it around, move it etc. Looks for some of the larger pins that are grouped at the end in like groups of 5. There is a ground wire in there. If it backs out...then no power to the TB.

Trace out the 6 wires associated with the TB. 3 are motor control and three for the pot.
Use a multimeter to test the voltages. What you may see is that there is a feedback issue with the TB trim pots. Not sure if it is a 12v or 5v signal but all your codes are pointing towards your TB being busted.
Also, the ecu should be trying to move the TB at startup (clear codes) and check for output voltage on the TB control wires.

Unplug TB. Clear codes. Cycle ECU power and see what codes come back up. If you get the ones for High feedback..you have a short or bad ECU. Your new ECU could have been killed by your TB.

Replace TB. They can be found for cheap online. Cheaper than a nissan "master tech".


Cam positions sensors...start replacing them.
If you have aftermarket LED brake lights...get rid of them. (probably not related just good advice)

561rpm

Cux350z thanks for the reply. Ive checked for each wire at the throttle body and what o have os constant power and ground but no signal to any of the wires when the gas is pressed. Does it only get signal when the car is running or should it get signal with just the ignition on?. Also the problem was not the ipdm bought a new one and same thing.

561rpm

Another new throttle body and still not a thing. Anyone have a pinout of what each pin in the throttle body harness should be getting?