Ok so I've owned my g coupe for over 5 months and had the greddy tt's for over 4 and about a week ago I started to have some problems.


I was on the highway cruising and all of a sudden lost all throttle. I pulled over to the side noticing a shiny "check engine light" on. THe car did not stall but however idled a little high (over 1K) and if I gave it gas, the highest it would rev to is 2k!!!

If I shut the car off, wait a few seconds and fire it up again I get only a few seconds before the ECU decided tu turn on what seems to be a "safe mode" and I have to repeat the on/off procedure to keep driving.

It seems to me like its a sensor. I left my car @ orlando Infiniti for over a week and they couldn't figure out what was wrong with it.

My mechanic told me it seems to be my throttle body OR the gas pedal sensor!? The throttle body ALONE is 900 bucks...

I dunno what to do. HAS ANYONE ENCONTERED A PROBLEM LIKE THIS?

Only apparent issue with my car right now is a broken Power steering hose and I'm getting it fixed this week but I don't have any reason to believe that the

After doing some research online, I discovered that this term is called LIMP MODE. I read someone say to clean the MAF with Carb cleaner and I will try that tomorrow to see if it helps.

I also read something about a CLAMP so that the MAF reads below so many volts but if I didn't need a clamp before, why should I need one now?

PS has anything to do with the engine dynamics.

 

Even though you have probably already checked this too, but are you sure the MAF harness is plugged in? That would make it run horrible.

 

I agree, I would check over anything that could have been broken during the install, maybe the MAF connector or coil clips, these coul dhave been cracked or broken and over time come lose.

What boost are you running?

 

All the coils are properly connected and the MAF is also. I'm running 5.6 psi (stock greddy setting). I have a BLITZ SBC I-color boost controller and was running 6psi but I disconnected it as soon as I started troubleshooting the problem and I ran all the vacuum lines back the way the turbo was suposed to go stock with no boost controller but this did not make a difference... It is still going LIMP

 

i am nearly 100% sure it is the throttle body/Throttle position sensor. Did you go through the throttle position learning steps upon completion of your install? Do you actually know what the code that is thrown is?

This is not an uncommon thing with drive-by-wire cars, especially when you add boost into the equation.

I would recommend, reseting the ecu while unpluging the throttlebody. See if the issue comes back. You cannot just replace the TPS, you must replace the entire throttle body. You can find decent used ones for around 250, but shouldn't have to pay more than 700 bucks new if you do need a replacement.

 

TP learning steps upon completion of install?

 

If its the throttle body, I have a brand new one. I bought for 800.00, i thought my throttle body was messed up. but it was something with my ECU. Let me know if you need it

 

Ok I personally don't know the codes but I can call Infiniti and my mechanic has them on file.

I havn't replaced the TPS or anything like that nor have I gone through any of the learing steps (hmmm, didn't know that had to be done). These learing steps only have to be done if the throttle body is replaced, correct?

My mechanic actually has a brand new throttle body in his tool box and I'm gonna test it to see if that fixes the problem. If it doesn't, then its back to square one.

If he tries to stiff me with the TB, how much do you want for yours BOOSTEDZ33TT?

 

ya figure out the exact codes and you will get a better responce.

 

I thought he had just finished install of the TT setup. What I am refering to is anytime you disconnect the throttle body, you need to go through a series of steps for the throtle body to learn the closed position:

Accelerator Pedal Released Position/Butterfly Valve Closed Position Learning
This must be performed whenever the harness connector to the “Drive By Wire” butterfly assembly or stock computer has been unplugged. This is a standard Nissan requirement
> Make sure that the accelerator pedal is fully released
> Turn the ignition switch to the “ON” position and wait at least two seconds.
> Turn the ignition switch to the “OFF” position and wait at least ten seconds.
> Turn the ignition switch to the “ON” position and wait at least two seconds.
> Turn the ignition switch to the “OFF” position and wait at least 10 seconds.

Either way it is most likely a throttle body/TPS realated issue. You cannot replace the TPS (throttle position sensor) solely as it is part of the throttlebody and the entire unit must be replaced together.

Again, this is not an uncommon issue with drive by wire cars.

 

Not sure why, but I don't remember that, haha. I guess I got a bad memory from a year ago.

 

i have forgotten to do this a couple times after messing around with my motor, and it never seems to make a difference if i do it or not. you will still have a position that the ecu will set it in right away upon start up. i know it is recommended, but i have never had it matter on mine.

 

Same thing has happened to my car on a couple of occasions. Its a TPS voltage corrolation code. Its seems to be sporadic, and not related to FI, as it happened once when I was NA. I unplugged my ECU for five minutes, and it hasnt happneed in several months.

This is different from the typical "limp" mode, which sometimes occurs when you nail the car WOT, and the MAF sees too much voltage prior to 4600rpm.
Becuase its one of the problems that is hard to duplicate, good luck trying to get the dealer to replace your TB. I have already tried. FYI...the TB's are about $500 or so...not $900

 

well here is the update:

Today I went down to OI and picked up a brand new throttle body that one of the mechanics had laying around and he told me to put it on, if it worked, we were gonna negotiate a price. However, I replaced the TB and nothing... The car started perfectly, I let it warm up and then shut it off. I then shut it off and finished putting my tools away and later tired to take the car for a spin and WHAM! THe sucker decided to go limp on me again!!!

I shut it off again and let it rest for a few mins and then took it out again and managed to get about a minutes worth of running time before it went limp again. I managed to get back home but the limpness continues to haunt me.

Oh yeah the power steering line I fixed today also and as I suspected, had nothing to do with the limp.

So... I got a brand new TB and PS working fine but the car refuses to run normally.
I forgot to get the codes from the dealer today but I will make sure I do that tomorrow.

I also tired: removing the pipe that comes out of the intercooler and into the MAF to see if the car would run fine without boost but it actually ran worse. It idled terribly low and didn't help at all.

I diconnected the Emanage and tried to run the car but again it didn't run right but I think that's normal because of the 440cc injectors.

Anyone got some other suggestions??

 

Are you sure the TPS is on the throttle body? Mine went bad when I was NA and the dealer told me it's actually near the gas pedal.

 

Do you have cats? When was the last time you checked the gap on your spark plugs?

 

Well well well... it is currently 3:13am and I just finished washing and waxing my car. THis is a big deal for me since as you guys know, my car had been in limp mode for the past week and a half.

I just finished fixing the car and it turns out it was some good ol' soldering that had to be done.

I took the car in a few months ago to a "certain" speed shop in Kissimmee and they they hooked up my greddy turbo timer. The reason I'm not disclosing the name of the shop is because they seem to be very defensive about people talking trash about them. I was actually approached by the owner, and two mechanics saying that they heard I was talking trash about their quality of work. Well... here you have it. Oh yeah and the broken power steering line I owe it to them also, they never followed the instructions on the TT intallation manual and I had to replace my PS line because the turbo housing was rubbing up against it. I will speak to the shop owner beofre I reveal the name of the place. Because I won't talk sh*t but i will say it to their face instead.

Well, after battling it out with Orlando Infiniti and over 200 dollars spent in towing and other misc expenses, it was the three ignition wires that the mechanic at this certain speed shop did so sloppy. The wires were simply twisted into the factory harness and never soldered (they barely had electrical tape on them, it was fallin off). Keep in mind that this was only done a few months ago so its not like the tape was old or anything.

Thanks to everyone that showed their support by posting on my thread.
I hope now that the car will stay ERECT.

 

I'm glad everything worked out for you. Enjoy it.

 

Definately try to get the code read, as it will undoubtedly point you in the right direction. It's going to be hard to trouble-shoot, without getting the code.

 

Ive had the exact same problem as you. Limp mode kept goin off on my car for a while and it was due to the fact that ALtered atmosphere cut up my wiring harness and did a **** poor job putting it back together for a nitrous install. Anyway Altered atmosphere didnt know how to fix it and basically said tough luck and so i had to get nissan to buy a new wiring harness because the repairs to the wires would still absorb voltage and send the car into limp mode. The new wiring harness was 1672 and im sueing Altered for that and a couple other things.