konrad

iTrader: (15)

check the wirering on the ECU, check for water, if you got another z to swap parts , swap the MAF

dj lizard

iTrader: (6)

check your throttle body. I know a friend of mine with a g37 had the same issue but not boosted. His had the TB F'ed. It was replaced. I have no idea if it could be the same issue, but Ijust trying to give in some feedback through prevues experience.


good luck,
-Meedo

str8dum1

iTrader: (11)

any update?

thatv35guy

iTrader: (1)

Nope, FML.

The car’s at Intense now, had them run a compression test (everything checked out fine on the compression test) and a leak down check is next.

Strange thing is no CEL for a misfire went off.

str8dum1

iTrader: (11)

and so your MAP sensor is reading properly. no stuck injectors/bad coil/crappy plug?

you said you have logs, you should be able to post the csv file

thatv35guy

iTrader: (1)

Well, the ground electrode of that sparkplug broke off and a bit of the insulator looks like it melted… swapped the plugs and it’s the same. I can’t post the log here, the file’s too big, could I shoot you an email if you wouldn’t mind taking a look at it?

str8dum1

iTrader: (11)

ahh cant see that pic since the forum seems busted. i can shoot you my email thru pm

thatv35guy

iTrader: (1)

Sent the logs and picture of the spark plug your way… thanks!

str8dum1

iTrader: (11)

so the electrode was actually broken on that plug of just opened up really far?

thatv35guy

iTrader: (1)

It broke off

str8dum1

iTrader: (11)

usually thats only caused by bad detonation. but you said your tune hasnt been changed?

thatv35guy

iTrader: (1)

Yeah, the tune hasn't been touched, the car just randomly started having an AFR in the 9's, I just drove it home from work and then to Intense, after that we pulled the plugs and found the plug in cylinder #2 broke. No misfire codes or anything.

str8dum1

iTrader: (11)

hopefully that piece just made it out the exhaust valve. i imagine a leak down will tell you that.

so even leaning out the fuel tables doesnt make any difference?

thatv35guy

iTrader: (1)

Yeah, I’m really hoping that spark plug didn’t do any damage… I’ve got just over 2k miles on this motor… I think I’m going to try and swap the MAF sensor out tomorrow and iA the leak down test turns out good I’ll have the car towed down to ProEFI later this week.

str8dum1

iTrader: (11)

your car is still using MAF?

Hopefully Jason can get it straight

thatv35guy

iTrader: (1)

Didn’t really think about that… I have the original MAF plugged in still, but I’ve got a ProEFI MAP sensor also set up.

str8dum1

iTrader: (11)

your car doesnt use the MAF for anything if you have a MAP sensor. Only intake air temp if you are not using a different sensor

mgrotel

iTrader: (3)

is that spark plug broke for sure or melted? its one or the other for sure. im suprised the compression test went good, my guess is that remaining piece of grounding strap is whats causing the problem. did something happen with the car when you first got the codes/bad running issues?

thatv35guy

iTrader: (1)

So, I went down to Intense last night and got a bit of good news, the car passed the leak down test. Mechanically everything’s sound, the compression test results from last week were solid as well. I’m going to try and pull the injectors and check them next, after that the car’s going to ProEFI as a last resort.

mgrotel

iTrader: (3)

could too much fuel (low AFRs) cause pre ignition and melting of plugs?
i know a lean condition can, but maybe if its too rich too?