Easy way to check for Air Leaks from Mass Air Meter - Throttle Body?

[Crowley]

Easy way to check for Air Leaks from Mass Air Meter - Throttle Body?

What is the best way to check for leaks? I ran a predator log on the car and the LongFTs and ShortFTs look fine .... I guess I'll look at the Mass Air Meter stuff now ..

this is in reference to my lean condition during my last dyno .....

btw .. from looking at the predator while logging I saw the following at idle:

LONGFT1 2
LONGFT2 4

SHRTFT1 fluctuated -3 to 0 back and forth
SHRTFT2 fluctuated -3 to 0 back and forth ..

thanks,
Crowley

 

[Crowley]

TTT .. added my Fuel Trim readings ..

 

[Shadowgray03]

The cleanest and safest way to check for air/vacuume leas is to use maap gas. You can buy the cylinders next to the propage and just use a propane nozzle on it. To get an idea how the gas effects idle just blow some in air cleaner and idle will pick up. With the car idling just direct the maap gas all oround blower, vacuum hoses etc and listen for idle changes.

As for a lean condition on the dyno and your fuel trims I am a bit lost. Your STFT's are pulling fuel which indicates a rich condition. Also keep in mind I dont beleive the fuel trims are used at all during WOT operation, they are used for drivability etc in closed loop.

 

[Crowley]

The cleanest and safest way to check for air/vacuume leas is to use maap gas. You can buy the cylinders next to the propage and just use a propane nozzle on it. To get an idea how the gas effects idle just blow some in air cleaner and idle will pick up. With the car idling just direct the maap gas all oround blower, vacuum hoses etc and listen for idle changes.

As for a lean condition on the dyno and your fuel trims I am a bit lost. Your STFT's are pulling fuel which indicates a rich condition. Also keep in mind I dont beleive the fuel trims are used at all during WOT operation, they are used for drivability etc in closed loop.

So with a Predator, what are readings that I can collect to figure out what happened during my last dyno?

thanks,
Crowley

 

[JoeNashville]

There might be "better" ways according to some folks, but the cheapest and fastest way is to mix soap in a squirt bottle/atomizer and spray it along the intake tract in an orderly fashion. When the idle changes you've found your leak.

 

[Shadowgray03]

So with a Predator, what are readings that I can collect to figure out what happened during my last dyno?

thanks,
Crowley

Tell us a little more about what happened, where it went lean etc, how lean did it go? What mods do you have??

I dont have a predator so not sure exactly what can be monitored but one thing you may want to log is fuel pressure, injector duty cycle FPDM duty cycle.

 

[Crowley]

Tell us a little more about what happened, where it went lean etc, how lean did it go? What mods do you have??

I dont have a predator so not sure exactly what can be monitored but one thing you may want to log is fuel pressure, injector duty cycle FPDM duty cycle.

I have a K&N .. with this, my last dyno was A/F of 11.8 or so ....

I got a Magnaflow catback, and catted x installed and uploaded a RWTD tune. This tune flooded the engine and would not run. I re-uploaded the stock tune and once it was running (about 7 minutes after being flooded), I put it on the dyno ..

after 4k the tail sniffer showed almost 14:1 a/f and up at the top end of the RPMS it only came down to 13.1:1 ..... to lean for me .. I don't know if it had anything to do with just being flooded or not ..... I got simular results for 3 dynos in a row .....

Now I drive it .. I just don't go WOT ....

thanks,
Crowley

 

[Shadowgray03]

I have a K&N .. with this, my last dyno was A/F of 11.8 or so ....

I got a Magnaflow catback, and catted x installed and uploaded a RWTD tune. This tune flooded the engine and would not run. I re-uploaded the stock tune and once it was running (about 7 minutes after being flooded), I put it on the dyno ..

after 4k the tail sniffer showed almost 14:1 a/f and up at the top end of the RPMS it only came down to 13.1:1 ..... to lean for me .. I don't know if it had anything to do with just being flooded or not ..... I got simular results for 3 dynos in a row .....

Now I drive it .. I just don't go WOT ....

thanks,
Crowley

I would have been off the gas long before it hit 14:1 on a WOT pull

With a stock EEC program you should be rich past 4k so you likely do have a post maf leak.

 

[Justin Blake]

I always just use carb cleaner. Its kind of messy but it works and you will know when you find it. I still think thats your problem. Let us know what you find.