I have a serious engine problem
 

serious, as in time sensitive

Car ran fine all day yesterday at ZCON autocross. This morning it has no power at all. It will rev all the way to redline in first gear, but I have the scan gauge hooked up to it and I'm not getting more than 15% on the TPS reading with the pedal all the way down. Have the battery disconnected now for a bit, then John from Z1 is going to hook the Osiris up to it in a little while.

I just hope I don't miss the track day tomorrow :(

oh yeah, no codes, no CEL

Have you tried to reset the ecu?

Good luck with this, let us know what happened and how you fixed it

Only by disconecting the battery for an hour. No joy

Good luck with the fix, Mike

Weird, Mass airflow problem???? Good luck and keep us posted.

What is your oil temp/ you might be in limp mode/ or it sounds like the MAF do you have aftermarket intakes?



DAN

Mike, you dont have to unplug it for an hour, you just have to unplug it and pump the brakes like 5 times. Sounds to me like an ecu glitch that will fix itself.

nope, nothing that easy.,
Fortunately, being at Zcon, I had the best minds from Z1, Forged, Injected, UpRev and Nissan Motorsports working on it, and noone has a clue what it could be. On one data logging run that Sharif did, while in second gear, it kept cycling between full and reduced power, leading the guy from UpRev to believe its a problem involving VVL, and that its probably a loose pin in the harness somewhere.

We reflashed the ECU with the stock tune, reflashed it with another Z1 customers tune and reflashed it back to stock. Did the accelerator pedal reset procedure, did the TB reset procedure and a few other things and nothing works.

Its gonna have to go the dealer and get hooked up to the consult-3 to go from here, but its not even throwing any codes. You would have thought they would have the consult at Nissan HQ, but apparently, they aren't allowed to have any tools there.

its back on the trailer, going home in the morning, no track day for me :(

On the bright side, I came in 9th overall in the autocross, and on street tires at that. Yoko AD-08s rock! They really behave like R compounds.

Sucks to hear you had to miss track day. Please post the solution when you've got it. You never know who could be next.

That sucks man, I hope it works out for you!

Good luck with finding the solution

Not going to miss the track day!!!! Sharing my good friend an zdayz CEO Bryan Settles beast of a 350z track car. It doesn't even have a dashboard!

Good luck. Sounds like the TPS crapped out or has a short.

I think I know the problem, but I am sharing my friends car for the track day anyways.

We came back from the awards dinner and my brake lights were on, on the trailer. They were on earlier, but I thought it was the exit/entry sentry lights,.

I also know that you can't power brake this car without pulling the abs fuse. brakes on, engine wont rev, period

I think my brake light switch or brake pressure switch has failed. that would explain no codes and cut power

Damn that would be a helluva thing

Could like a faulty relay. Hope you get it all worked out!

think it could be another ipdm the seemed to be faulty a while ago but then people stopped hearing about them.

nope, it was the brake switch. Stopped by Gwinnett Place Nissan on the way home today, and the mechanic came out and looked at it on the trailer, and the switch was out of adjustment. 5 minutes with a wrench under the dash and he fixed it, we didn't even do any paperwork or anything.

Although, the parts manager, who is a friend of mine said they have been seeing a fairly large number of switch failures lately at Nissan on the Zs.

Thanks for sharing the fix, Mike! This is good info.

Good you found the problem!

Huh? I don't get why the brake switch would cause the problems you were having with TPS readings :confused:

Did the ECU think the brake was fully depressed when it wasn't? :confused:

yes, the 350 and 370 both have this feature programmed in that says if you are braking, there is no reason you should also be accelerating, so it won't let the throttle open more than 15% if the brakes are applied. With the switch sending the signal that the brakes are on, it was restricting the throttles.

Anyone that drag races these with slicks knows they have to pull the abs fuse to power brake it and do a burn out. Try it sometime without doing that, the car won't do it.

how do people heal toe with this feature?

you don't need hardly any throttle to rev the engine with the clutch in and besides, with the rev match shifting the 370 does, you don't need it anyway.

that sucks you didn't get to drive your own car mike but at least bryan let you take some laps in his. i'm hoping to get some seat time in the beast at the next A/V track weekend coming up :tup:

Huh. So no brake-stand launches for the autos then...?

Indeed. I'm no noob to launching or doing a burnout in an automatic, so we took the Z out to the middle of the desert (literally) and I tried a few burnouts/launches. As Mike describes, as soon as you apply throttle while braking, the engine cuts power. I was able to get maybe 1.5 sec of brake-torquing before the engine cut power. Needless to say, no burnouts were achieved that day.

It actually makes for a very poor launch...

Well that sucks.

I guess it's just as well since we have no way of checking to see if the ATF is burnt from doing that...

I was able to lay wheels pretty nicely just flooring with the traction control off tho :D

You could always install a switch on the brake wire going into the ecu to disable that function when racing.

yea, but it wouldn't have been good to either have no brake lights, or brake lights always on while on the track in traffic. For burnouts and drag racing, people just pull the abs fuse.

I think most drive by wire cars have this "feature" these days (throttle cut on brake activation). Toyota wishes they had it..:shakes head:

Glad you figured it out Mike!

Yeah, this was one brought-up during the Toyota fiasco, and Nissan was given kudos for having this feature over Toyota!

LOL~ :icon18:

Wouldn't have helped if Toyota's issue were mainly user error - but may have made it obvious to the media.

Given no brake torque, what is the best way to launch an automatic 370Z?

Yes they do have it on some cars

You can still launch it by brake-torquing, you just have to be quick. Basically, it has to be one fluid motion: hold brake firm, floor the gas, release brake. All within 2 seconds or so.

In a drag strip scenario, I'm going to try to pull this off right as the next-to-last light on the tree appears... Skills yo :bowrofl:

It hits flash stall so fast 2 sec seems like plenty of time. I tried this earlier today, and it worked fine :tup:

I always thought after about 5+ sec you start cooking the trans fluid anyway...

A line lock should work the best when trying to launch. It locks the brakes hydraulically and holds it until you disengage the switch.

Yeah but yota's problem was shown not to be user error in several cases most notably the one with the old guy in the prius going 60 on the highway with his brakes smoking and a squad car got in front of him and used his brakes to slow the car down. (don't know why the guy didn't shift into neutral but w/e it shows yota fudged up)