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Mike M
07-31-2014, 03:30 PM
Like last year my IAT run between 140-150 and when that happens all hell brakes loose. Coming off the interstate cruising at 85 slowing down to an exit and stop light I look down at my wideband and see super lean mixture (off the scale) and the engine shakes and dies. Fuel pressure at that point drops to 19 right before it dies. Barely get it started with hazard lights on and limp to my shop. Let it sit for an hour with hood open and it starts and runs fine.
When the weather breaks this problem goes away.
I am assuming it has to do with the high IAT temps.

It is hot out here, today only 108 but it gets hotter then that until Sept.

I would love to modify the IAT with a resister to tell the computer its 20 deg cooler as an experiment.

Feel free to to give your opinion.

Blackened300a
07-31-2014, 10:42 PM
Is your pump working and circulating? In hot temps when hard on my car, I've only seen 135* max. Most tuners set the tune to pull timing if the IATs reach too high. 150 is pretty high. Where is your IAT sensor located? Mine is in the mounting plate on top of the intake behind the blower.

Mike M
07-31-2014, 11:47 PM
Is your pump working and circulating? In hot temps when hard on my car, I've only seen 135* max. Most tuners set the tune to pull timing if the IATs reach too high. 150 is pretty high. Where is your IAT sensor located? Mine is in the mounting plate on top of the intake behind the blower.

I am running a air to inter cooler. My IAT is in my MAF at my air filter.

Marauderjack
08-01-2014, 04:27 AM
Where is "out here"........Earth is right big??:cool:

If you fool the PCM about the IAT's it will not pull as much timing and you will surely detonate if ya romp on it!:(!

I think I would find another way to richen it up when hot.....perhaps Zack will have ideas??:confused:

BTW, I have seen IAT around 145* quite often with no idle or performance problems except power drops off!!:shake: I only run about 9 PSI though!!;)

Good Luck!!:beer:

Mike M
08-01-2014, 09:15 AM
Where is "out here"........Earth is right big??:cool:

If you fool the PCM about the IAT's it will not pull as much timing and you will surely detonate if ya romp on it!:(!

I think I would find another way to richen it up when hot.....perhaps Zack will have ideas??:confused:

BTW, I have seen IAT around 145* quite often with no idle or performance problems except power drops off!!:shake: I only run about 9 PSI though!!;)

Good Luck!!:beer:

------------AZ---------------

Limited360
08-01-2014, 10:50 AM
Well with the fuel pressure dropping I wonder if your having issues with your FPDM or possibly vapor locking the rails?

I would not fool the IAT, that isn't causing the problem in my eyes...

JohnE
08-01-2014, 11:09 AM
Your IAT should always be measuring the temperature that is entering the engine, not the inlet to the blower. Is this a blow-through MAF or traditional setup?

Also, make sure you draw fresh air and not under-hood air. Air heated by exhaust headers and the radiators is not ideal to start with. Slow moving, it causes horrible tip-in response. Once you are moving over 30mph, the air isn't too bad.

Mike M
08-01-2014, 12:51 PM
Your IAT should always be measuring the temperature that is entering the engine, not the inlet to the blower. Is this a blow-through MAF or traditional setup?

Also, make sure you draw fresh air and not under-hood air. Air heated by exhaust headers and the radiators is not ideal to start with. Slow moving, it causes horrible tip-in response. One you are moving over 30mph, the air isn't too bad.
Traditional set up, air comes in the air filter then immediately the MAf.

The fuel could be vapor locking, hard to say. I have a upgraded FPDM.

MOTOWN
08-01-2014, 01:17 PM
I would convert to a blow thru setup then your IATs will be measured after the intercooler , and what air to air intercooler are you running?

Mike M
08-01-2014, 01:43 PM
The ProCharger intercooler that came with the kit.

Mike M
08-01-2014, 01:47 PM
If I move the IAT to the inlet before the throttlebody, wouldn't that be more accurate?

Right now the IAT is measuring basically under hood ambient temps. If i move it to the inlet right in front of the throttlebody it would seem to make more sense to me.

MOTOWN
08-01-2014, 01:50 PM
If I move the IAT to the inlet before the throttlebody, wouldn't that be more accurate?

Right now the IAT is measuring basically under hood ambient temps. If i move it to the inlet right in front of the throttlebody it would seem to make more sense to me.

That would be a "Blow thru setup" if you move the MAF before the T/B , which is what i would do, and in that AZ heat you could use a better intercooler as well.

Zack
08-01-2014, 02:05 PM
Get a DY754 sensor and weld in a 3/8npt bung.
Add it into a piece of pipe that has the most straight run. (usually right around the ABS pump height)
DO NOT WELD IT INTO THE ELBOW BY THE TB.
Lots of turbulence there.

Zack
08-01-2014, 02:08 PM
Or (even better) weld in an 05+ MAF flange and get a MAF from www.poweraddersolutions.com They sell a re-badged Pro-M for 50+ dollars cheaper.

Get a pigtail from the boneyard.

svtrichie
08-01-2014, 08:22 PM
Temps are that high even with a meth kit. Are you using it for cooling at all. Also who does your tuning in az.

Mike M
08-01-2014, 08:31 PM
The meth is injected after the IAT.

The tuning question is complicated but basically I don't know anyone out here that is good. I'm not saying there aren't any...just that I don't know any.

Don't get me started with the $500.00 + I spend on Delta Force software.

Mike M
08-01-2014, 08:32 PM
Or (even better) weld in an 05+ MAF flange and get a MAF from www.poweraddersolutions.com They sell a re-badged Pro-M for 50+ dollars cheaper.

Get a pigtail from the boneyard.

Interesting.