well here is the problem I am having with the truck. when ever i get in it, havent driven it in a few hours, i notice something wierd! my truck is idleing fine, but if i have any lights on to tell it is really doing it, i can telll in the lights because the go with it. my viltage drops do about 1/4 of the voltage gauge, and then goes right back to over 14 once it hits that certain low. and u can tell in the head lights it is doing it. and you can ALSO hear it! any ideas?

thanks!

 

has it been getting cool there? grid heaters in the intake, should stop after over about 20 mph.

 

this may help you...... http://www.cumminsdatabase.com/read.php?id=33

 

grid (intake) heater. 5.9 cummins dont use glowplugs to heat combustion area. Only duracrap and powerjoke use glowplugs. instead we have a intake heater that heats the air to aid in combustion.(just for cold startup)

 

yup, totally the grid heater, mine does the exact same thing... no worries..

 

the grid on his truck is different from newer trucks in that it's controlled independently from the ECM. It has it's own controller that could be going bad and not the grid itself. There could also be a bad ground somewhere causing it to work intermittently. Bad temp sensor could also cause it to work erratically. those are also known to be a problem causer to make the heater grid malfunction

 

damn! for a second i thought i didnt have nothing going on. It has not been tooo tooo cold, maybe in the 20's ONE time...rest of the time 30 - 35s.How should i test it to see what it is or how can i figure it out for sure!?

 

alright after reading that, i figured it out! i am going to try that monday and see what happens.

for those of u that didnt click the link:
The IAT sensor measures the temperature of the intake nmanifold. The ECM uses this sensor reading to set injection timing and adjust the air-fuel ratio. If the fuel mileage and power output of you engine seem low, some owners have found improvement in EGT, fuel economy, and power after cleaning carbon from the IAT sensor in at the rear of the intage manifold. Engine with exhaust brakes are particularly prone to IAT sensor fouling because soot is blown back into the intake during valve overlap. Smokingdiesel.com has an information page about problems caused by the IAT sensor.



Thanks trition! ill let you know!