dirtbikr

Hey all,

Haven't been on here for a long time, guess it speaks to how reliable the Z has been. I bought mine (2007 Touring AT) in 2008 with 12,000 miles on her. I've done all my routine maintenance, and just went to replace the plugs on Thursday since I was at 107k.

Pulled the intakes out, and then pulled the throttle bodies off and set them aside. I had already done my research that a lot of people have issues after cleaning them and have idle issues, usually it is resolved with the pedal dance. So like the anarchist I am, I cleaned them very gently with a bunch of rags, Q-Tips, and some throttle body cleaner. I did not open the butterflies by hand or move them at all. Changed the plugs out with the stock Denso plugs from Nissan, and buttoned everything back up.

Cold start acted as normal, went up to about 2k and then idled down like usual, but it would not idle under 1k RPMs, and then as I left the car on, the RPMs slowly crept up to 1750 (over a period of six or sever minutes), then they would dump down to ~1200 and repeat the process over and over.

I have checked for vacuum leaks, I have sprayed carb cleaner around all fittings, and I am very sure there are no air leaks post MAF sensors. The car is a beast on the freeway, and feels better than it has in a long time, but there is about a one second delay from lifting foot of the throttle to when the car registers it, very apparent when the transmission is in lock up.

So here I sit, I have done the pedal dance numerous times, and I even have a scan tool from autoenginuity that allows me to perform the "Idle Air Volume Relearn" just by pressing a button instead of the little dance. Nothing is working and the car will never idle under 1k RPMs. The only time it drops that low is when it is in gear, and I imagine I am not doing the tranny any favors by running it like that. It will also throw a P0507 if it is in neutral or park for a couple minutes, but that is expected with the idle so high.

All the research I have done has been inconclusive, and nobody has reported any real remedies. I'm not sure if I should go with eBay throttle bodies and try that route, but if anyone has any experience whatsoever with this I would appreciate it. If you live in the Phoenix/Tempe/Mesa/Scottsdale area and would be willing to troubleshoot with me that would be awesome and I'll buy you a case of beer or dinner or whatever you want. I just want my Z back .

TL;DR: Cleaned throttle bodies while I was doing plugs, car will not idle correctly, and the peddle dance and a scan tool similar to the Consult system is not working. Looking for help from anyone afar and local!

rcdash

iTrader: (18)

Do you have the FSM and have you followed the procedures for TB, idle air, and pedal relearn? Did you disconnect the battery before you disconnected the throttle bodies? Did you try an overnight battery reset?

dirtbikr

I do have the FSM and have been using it as the guide. Followed Accelerator Pedal Released Position Learning, Throttle Valve Closed Position Learning, and Idle Air Volume Learning (using my computer and the pedal dance, neither have worked). I also verified that all of the parameters were within spec (Voltage > 12.9 at idle, Coolant temp between 158 and 212, in park, no load, steering wheel straight, trans temp sensor 1 < 0.9V). Battery was disconnected the whole time the throttle bodies were disconnected, and I have left it unplugged for 24 hours, still no go.

I disassembled everything again and the only thing I notice is the passenger side throttle body makes a kind of "twang" sound when it is tapped on with a finger, and the driver side throttle body does not. They both function in the sense that putting the car in drive or reverse and having someone touch the throttle while the car is off results in both butterflies moving as I would expect. Something else I never noticed is that they "whine" when the car is placed in drive or reverse, but I have honestly never had the car on in drive or reverse before without the engine running, which would mask that noise.

dirtbikr

Bought a used driver's side throttle body out of a wrecked G37 and installed it. The car idled down properly and then I took it for a drive around the neighborhood. When I came to a full stop the first time, I had VDC, SLIP, and SES lights come on and lost all throttle control, and had to restart it a couple times to get it to move. Went back to the house and pulled the code (P1223 I believe, electric throttle control problem). Cleared it and it seems to be fine since. I drove it to work, and drove it back that night.

The only issue I noticed was that when I got off the freeway on the return trip home and put it into neutral at the light, it idled at about 1100RPM, and did the same thing when I pulled into the garage. I don't know if it is just trying to relearn or if something else is going on. I'll keep everyone updated. Any more thoughts are welcome!

350Speed

iTrader: (20)

dirtbikr,

Have you had your issue resolved?

I'm having the same issue after cleaning my TBs. I did manual relearn but still didn't work.

Thanks.

Ruined Z

iTrader: (23)

I had the same issue after I cleaned my TBs. What got me into the idle mess was that I had one of the TBs unplugged when I hooked up my battery.

Plugged it back in and I had the same idle issue. I did the pedal dance a million times and it never got better. I took it to my mechanic and he used his CONSULT device to do the relearn. Issue never came back. If you can go somewhere with that device, go there!

350Speed

iTrader: (20)

I went to dealer for reset but still didn't work. The tech told me it could bad ECM. Expensive throttle body cleaning lesson learn.

zakmartin

In all the years I've been on this board, I can't remember a single instance when someone removed their throttle bodies and didn't have the car go ****-up on them.

0jiggy0

iTrader: (13)

I cant believe the ecm weNt bad. I would check again for vacuum leaks.

kham25

iTrader: (3)

Going through same thing changed ECM both Throttle Bodies and MAF sensors. Car still idles high and bogging down. Dealer says all live data shows everything is fine. I given up and just drive the damn thing now .... Last f@cking nissan I'll ever own, 3 dealerships all clueless. .

350Speed

iTrader: (20)

After three days leaving the car in the garage, I started the car and the the idle was still high at 1250-1400. The different from this time is it didn't fluctuate between 1500-2000like before. When I first started the car, it did drop to 1000 and stayed there for about five minutes.

As far as I know, there was no leak. This issue is so frustrated!

350Speed

iTrader: (20)

I tried idle relearn again today. It's now stable at 1250.

technic05

Is the ECU up to date? There's an ECM reprogram available for 2007-2008

PercisionDriver

iTrader: (1)

This is nuts. I just went through the same ordeal. Also, side note, I did have the updated ECM done a while ago, still got this issue. Battery was disconnected, and still left the TB plugged in and cleaned it that way. I did move the throttle plates, and I'm thinking that may have been what done it. I was getting the 1500-2000 dramatic fluctuating; so the extra bad version of what people get. This was solved with new used throttle bodies off ebay. I want to try and see if I can get the old TBs working again, but i'm so afraid of unplugging or messing with the TBs now.

gabez33

iTrader: (7)

I read somewhere that if you un plug the TB's then the battery, then the ECU, and do a power drain/or leave it a good 3+ hours...it reset EVERYTHING. Its the only thing that worked for me

Doc_Z

Dafuq! Same issue here! Someone should go and update those ****en how to posts on changing spark plugs and maybe mention the fact that removing the tbs will **** up your life!

Doc_Z

Anyone tried replacing the rubber orings on the tb's? Nissan mechanic I know says its a common problem on the Tiidas with a similar setup once guys disturb those seals.

Doc_Z

Ok so sealed up the TB seals with a touch of silicone to ensure they're not leaking, also replaced all the clamps on the intake piping and related tubing. Did the pedal dance again and I still have this issue.

The dealer also tried the idle volume relearn procedure a few times and it would not take. The Consult would say "Executing" but nothing happens. I have no error codes.

My idle is somewhat high at around 1000-1100 rpm with a bit of surging or delay on the acceleration/deceleration etc. It's really really annoying and is making me hate this car. If I can't get it fixed I'm selling it. I just dropped a bunch of cash on a new clutch, full service, belts, fluids, plugs etc. What a waste. Try to make something better and now it's ruined.

Doc_Z

Also, when the cell stops blinking (step 9) do you switch the ignition OFF before starting the car, or start it right from the ACC position? to go onto step 10?

Also, how do you check step 13?

NOTE:

It is better to count the time accurately with a clock.

It is impossible to switch the diagnostic mode when an accelerator pedal position sensor circuit has a malfunction.
1. Perform EC-42, "Accelerator Pedal Released Position Learning" .
2. Perform EC-42, "Throttle Valve Closed Position Learning" .
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREPARATION (previously mentioned) are in good order.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.
7. Repeat the following procedure quickly five times within 5 seconds.
a. Fully depress the accelerator pedal.
b. Fully release the accelerator pedal.
8. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the MIL stops blinking and turned ON.
9. Fully release the accelerator pedal within 3 seconds after the MIL turned ON.
10. Start engine and let it idle.
11. Wait 20 seconds.
12. Rev up the engine two or three times and make sure that idle speed and ignition timing are within the specifications.
13. If idle speed and ignition timing are not within the specification, Idle Air Volume Learning will not be carried out successfully.

gabez33

iTrader: (7)

DID you try the steps i told you?

If the ECU says executing and nothing happens all signs are pointing to your ecu is hosed