2007 350z Idle Surging (I know..)
 

Okay I know this has been covered a thousand times but I am really at a dead end with this and I need some advice badly.

I have the dreaded surging idle after a throttle body cleaning.

I needed to change my spark plugs so I decided to pull the throttle bodies instead of the entire intake. I did NOT remove the negative cable from the battery before unplugging the throttle bodies. I did not move the butterflies before unplugging them. I cleaned them with throttle body cleaner and a rag, never did I spray cleaner directly into or onto the throttle bodies. There was little to no daylight around the butterflies before the cleaning, small hint of light most of the way around the plates after cleaning so the car is defiantly getting more air at idle now.

Things I have tried are... Manual reset with pedals/key. Have done all three resets numerous times. SES light flashes accordingly and have also done the ECU reset which I can verify by the SES light going out while the car is running after I perform the reset. I did ALL of the resets by the book, with a stopwatch, getting the correct responses and timing back from the SES light. No difference in idle, still surging from 1500-2000. I am NOT getting the "its fixed till I restart" like a lot of people have. It is having ABSOLUTELY NO EFFECT on my idle. The only thing I can tell is the throttle bodies are moving, have verified this with a second person turning the key while I look, and I am doing the resets correctly. I have cleaned the MAF and 10x checked all clamps and hoses are tight. No leaks around the throttle bodies themselves, checked with a spray bottle no bubbles or effect on idle. I have unhooked the battery for 12+ hours and then tried the reset with no luck, still surging. Last but not least I broke down, took it to my local Nissan dealership, and let them steal $100 from me to fix nothing.

Here is what I have discovered from my dealership trip.. They hooked it to the Consult II system and tried to run the reset. There are several things that must be correct before you can do the relearn, manually or with the Consult. Battery voltage while running, steering neutral, shifter position, temps, A/C load, voltage load, vehicle speed, and lastly OPEN or CLOSED loop. Well I was good on everything but the open and closed loop. Every time the throttle surged, the loop would open and the test wouldn't run. This prevented him from even running the test at all. When it did start, it failed immediately when the idle surged. I had read somewhere in a Nissan service bulletin that it was required to unplug a few injectors to drop the idle and run the test on some cars. It also said you may need to unplug up to 3 injectors to get the first test to complete at which point you plug them back in and run the test again for a final relearn. I mentioned this to the tech that was working on my car and he took a quick look and said yeah I can get to the #1 injector pretty easy so I may try that. At that point he needed to let the car cool down for 2 hours before he could attempt the test any more and my "tech time" was up and I was ushered back into the customer area. Long story short, 2 hours later I check on the progress and find out they still couldn't get the relearn to run. He supposedly did pull the plug on ONLY the #1 injector and the test would still not run. I was not told if it dropped the idle, stopped the surging, or had any effect at all when the injector was unplugged. Perhaps he needed to unplug more then 1 but due to the location of the plugs wasn't willing to do what was needed to access the plugs?? 5 Hours wasted at the dealership, and $120 later I still can't drive my 350z. I just wanted to clean it so it would run BETTER! If the dealership can't fix it then where do you go? I can't keep spending $120 or MORE every time till I find a dealership that knows whats going on.

I have a pro shop locally that does work on imports and has done a lot of work on my 300zx so as a last ditch effort I asked them. He is familiar with the problem and has heard of a tool that can reset it for me. Will be calling me tomorrow with what he finds out and if he can get the tool. Anyone know what he might be talking about or if there is something that can do the relearn even if Nissan's Consult II cant?!

I need help. I have read HUNDREDS of posts about this exact same issue (and some similar). Most were able to get it reset at Nissan after the pedal dance failed. About half the idle is actually surging and the other half its just a high idle, mine is SURGING. Some have spent big $$ replacing throttle bodies and ECM's and it seems it only works sometimes, for most the problem remains.

If you have a solution for me, even a shade tree one, I am listening. I'm about to go put bags over the intake and force the idle down or SOMETHING I am so angry at the whole situation. I went to two other dealerships and all they could tell me is they will diagnose it for $100, and another $93 to attempt the relearn. How do I know they will have any more luck then the other master tech I took it to? They wouldn't even let me speak with the master tech on duty to ask if he had any ideas after I explained I have already spent $120 at another NISSAN DEALER and they couldn't fix it. So before I light the car on fire and claim insurance (not really) help me out fellas!

I am south of the DFW area and am normally off on Sundays and Thursdays. I drive a 2007 Nissan 350z Touring with a manual transmission. The car is completely stock except for a few cosmetics and K&N drop in filters for the stock air box. If you want a look at it I can drive it short distances and am more then willing to bring it to you if you think you have a shot at getting it back in order. Shoot me a text or call at 817-874-8710 if your in the area. Id love to try someone else ECM or throttle bodies if you were willing.

Thanks in advance

Replace the TBs - it looks like you've tried everything else that's normally suggested.

I'll take "shadetree" for 100.......

It looks like you've been very thorough and methodical in trying to solve this. I've also been down a few roads where something worked just fine a moment ago, then stopped working right about the same time I was fiddling with it........then about six steps into the remedy for what was originally working just fine.....:suicide:

The only "known" here is that it was working fine before the new plugs and cleaning, so you are going to need to go back to that point. The problem with compounding solutions is that Fault 1 was addressed by Fix 1, then Fix 2, then Fix 3. We get far enough down the line that we don't know if Fix 2 caused something new, or if a combination of Fix 2 and Fix 3 worsened something....and so on. For all you know, you may now have Faults 1, 2 and 3, with no end in sight.

I hate to offer little more than this simplistic approach, but it has worked often enough to have merit. I need you to go all the way back to the point at which you decided to change the plugs. Start by pulling the intake and pulling all those plugs out. Then set all the parts out and take a break with a cold drink. Go to the basics, dot each i and cross each t before you proceed. Replace the plugs with the same type that were in there before. Triple-check everything before it goes back on.

If you continue to have the problem, don't add a solution without undoing the solution that didn't work.

Texted you! I will post later today when mine is fixed!

Ohm testing?
 

Thanks for the replies! Still looking for a solution if anyone has any insight. I was going to do some testing of the components that might be non functional.
Is there an Ohm test or something similar I can perform to test things like the MAF and throttle bodies? ECM test of any kind? I have no SES light except the occasional high idle code. I have cleaned the MAF and obviously the throttle bodies but would like a way to test what I can before I pay Nissan $300 just to diagnose it.

Will be posting a link to a video showing exactly how the car is acting and how I am doing the resets.

Thanks

you sure that your TB gasket is pointed the correct way, it is directional.

Gasket should be straight and correct. I did not touch the gaskets. I removed the throttle body and left the gasket in the intake manifold. I did make sure I got the throttle bodies back on flush and very tight. I also tried the ol method of spraying water around the throttle bodies to check for leaks. No bubbles, no change in idle. However as I am running out of options I was planning to remove the throttle bodies again and pay extra attention to everything as I reinstall them. Thanks for the suggestion, I will triple check the seal on the throttle bodies.

Videos of the issue.
 

Okay here are links to a couple videos I made detailing the issue and showing what I am doing.

The first one is showing how I cleaned the throttle bodies and how careful I was:


The second one is showing exactly how the car acts on a cold start, and how I am doing the relearning procedure. I am aware that the car must be warmed up to do the relearn, I have tried MANY times while it was warm. This was just another attempt to try something that was suggested by another Z guy and is more for reference that I have the timing correct then an actual relearn attempt:


About to spend what I am guessing is a fortune at a different Nissan dealer tomorrow hoping they might have a tech that knows more then the last guy. So if you have any insight I am still looking for a solution. Also anyone in the DFW area willing to let me swap ECM's or throttle bodies to test these parts I'll gladly buy ya some beer and pay for gas to make it worth your time!

Thanks for all the feedback so far.

The car definately needs to be at operating temp (158*F). Like you suspect, the other people didnt perform the reset properly.

I would pull the TB's, replace the o-rings and reset after driving the car for a while. Make sure the engine is very hot.

Here's another angle: You could hook up a scanner to your car while it runs and check parameters to see if something is running out of spec. You could then compare your numbers against a known proper set. I know your car isn't throwing codes, but comparing against some benchmarks might narrow it down for you.

I've got an 05 MT all stock. I can run my Autel AL 619 on it and get you all kinds of data on a stock configuration that is running normally.

Having same problem with my 07. I came home from a deployment 2 days ago and got my Z from storage. I had the battery disconnected for the entire 7 months and the car was never touched. She started right up no problem, I drove it about 15 miles and all of a sudden my SES light came in and the idle is jumping up and down (same as in the above vid) Only mod is a JWT Popcharger. I am going to pull those off, clean the filters and do the resets from above and hope I get a fix.

Update:

Took the car to Bankston Nissan in Irving. These guys were WONDERFUL! They brought the lead tech out and let me talk with him, reprogrammed my ECM and ran diagnostics on everything for a minimal fee. MUCH cheaper then other dealerships were wanting.

They tried everything... Pulling injector plugs, and anything else they could think of but nothing worked. They did some diagnostics on the throttle bodies and dertermined they were at fault. Apparently unplugging them without first unhooking the battery must have caused damage.

Nissan wanted $1900 to fix it, charging $700 for each throttle body. I found OEM new replacements on eBay for $450 for BOTH. Ordered them, nissan said $350 to install if I bring them the parts. As I was leaving the tech stopped me and we had a discussion about it. After talking with him he assured me that as long as I unplug the battery first I should have no trouble installing and reprogramming them myself.

Parts are on the way. Will post another update after I try to install them. We will see if this is really the problem once and for all.

This was in reply to a private message I got. Still no fix for my idle yet... Help me out guys!!

Man I wish I had good news for you. Yes you should be able to remove the battery cable FIRST and then clean whatever you need to. However I have NOT been able to fix my problem. I ordered throttle bodies off eBay (buyautoparts) and they seem legit enough. Match my OEMs exactly and don't appear rebuilt. I did notice however the branding on the top of the throttle bodies are ground off. My OEMs say Hitachi, Nissan, and something else. The replacements from buyautoparts have had the two brandings below Hitachi ground off leaving just the Hitachi stamp. Shouldn't effect anything but I thought it was odd.
Anyway point of this is that I put the new throttle bodies on, making sure to unhook the battery first, and it didn't fix a freaking thing. After the Nissan tech assured me 100% that it was my throttle bodies $500 later and the idle still surges. I'm freeking out now as I am pretty much outta cash and my 350z still doesn't run right.

Two things I am going to mention however that I hadn't previously is that I did install the K&N panel filters (OEM replacement not cone type), and I used NGK Iridium spark plugs. NGK part number DILKAR7B11. These were the ones O'Rileys sold me. Normally I double check but on the newer cars they usually have correct part numbers.

I am still looking for a solution for my problem. Next steps I am taking are ordering new throttle body gaskets, and getting some OEM Denso plugs to install.

-Alex

Hmmm. I'm trying to brainstorm here. For some reason I don't know why I was thinking to change out the inexpensive PCV valve, but I was. You've so many remedies already. I believe I was thinking of the PCV valve because I had a vaccuum leak in a much older car. I can't remember...

Not sure where the op is on his problem but here is a update on mine. I took the Z to Aero auto here is San Diego. They are the local 350Z pros. They used to be Z whizz. These guys are awesome, they were super honest and right up front. They took my car in a told me it was throwing the IAC code. The computer would not let them in for long enough to let them look at the problem. So they said take it to Nissan and any ECU issue is covered up to 80,000 miles. My car has 50,000. So I take it to Mossy Nissan on Clairmont Mesa Blvd and they tell me its the MAF sesnsor and it gonna be $958 to get and install them with the throttle re learn and a full fuel system flush. I told them ok just fix and and they called me today and said yeah its still not running right and we dont know why. We put our best guy on the job and he is going to call the Nissan hotline tmr cause he had no clue. So what the hell is wrong with my car? Its getting a little redic that even the cutthroat dealer cant fix it.

tearing my hair out
 

I did the same thing as the OP (also a 2007 HR, 6 mt), got the same surging results so far

3 dealer visits

1) try to reset idle with consult, didn't work

2) used throttle bodies from ebay, try to reset idle with consult, didn't work. Dealer says he put TBs from another car on, and it worked fine.

3) New throttle bodies from ebay, these are the hitachi OEMs with the brand filed off. Didn't work. Dealer again says he put TBs from another car on.

Took my car to a specialty mechanic who modifies cars, he took it to a dealer after he got nowhere, says that he saw with his own eyes that they put the TBs from another car on and idle stopped surging and dropped to 1k.

Dealer wants US$ 5.000 to import new throttle bodies (I'm in Chile so everything is absurdly expensive). I am really not happy about the price but all of the parts I have imported myself have not worked out.

Hope that the OP can shed some light on this if he gets things worked out.

Has anyone here tried a new ecu? Might be a last ditch effort.

resolution
 

Ok, my problem is for the time being resolved:

Last week, I am about to take the car in and just pay through the nose for a fix. Service rep says before giving me the budget he's going to let the tech have one last try before ordering throttles.

I bring in the car with the original throttles, a pair of throttles from an 08 G35 with the HR motor that I bought used from Ebay, and a pair of new hitachi "brand scratched off" throttles that I bought from Parts Monster.

The tech got the car working on the used G35 throttles. According to him, the "brand scratched off" throttles have different factory positioning of the little screws on top. Rep called me and I told him to do the 40.000 km service. I got the car back and it's running great, Idle is even a bit low at 550-600, which is fine as the car passed emissions yesterday.

My advice to anybody who has "normal" ECM behavior and can't get new white box hitachi throttles to work is to try to source used original throttles from Ebay. It worked for me and I have literally been to 3 different dealerships, imported new or used parts 3 times, and it's been almost 6 months to the day since I originally f-ed up by cleaning. Good luck to everybody!

DRUNkPUNK ! yo bro i called u about the same problem like a couple of months ago, i live in california. okay so i had the same problem, i have a 07 350z hr with 70k on the mortor stock everything base model. okay so i had the same problem did everything u guys did but ..... i think i only paid 95 bucks ..... for the diagnostic and for them to tell me whats wrong. but right when i was about to order the new tb's i had to wait for the money to come in first so i was driving for a month or so with messed up tb's. but the thing was my car fixed it self.. my best friend at UTI told me that my car was in "limp mode" and thats it .... u just have to drive ur car and hopefully ur computer catches on and fixes it self... what i did... drove on a empty tank of gas all the time (reason no cash) lol and i got tired of ricer kids trying to race me cuz they thought i was revving my engine to race with them so everytime i got to a red light and i knew it was going to be long wait i turned off my car. mostly all and all thats all i did ... but 100% credit to my ecu !

Well the problem is fixed. I took my car to Nissan with the new throttle bodies, same thing. They said it has to be the ECM. So I send my ECM off for repair, after testing, nothing is physically wrong with it, has to be in the logic. Ordered a refurbished ECM/ECU, took it to Nissan for key reset and idle reset. Car runs perfect now.

Grand total spent on parts and labor.... $1800. Hoping to recover $500 or so selling the new throttle bodies I ordered and can't return.

Link between the throttle bodies and the ECM is NOT fused. Make absolutely sure the battery is disconnected and the residual power drained before you do ANYTHING with the throttle bodies.

-Alex