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

 

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

 

any update?

 

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.

 

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

 

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?

 

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

 

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

 

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

 

It broke off

 

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

 

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.

 

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?

 

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.

 

your car is still using MAF?

Hopefully Jason can get it straight

 

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.

 

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

 

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?

 

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.

 

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?