Smkn600CTD

Its 105 degrees outside, and the wait to start light stays on like its 20 below. After starting it up, the light goes off, but the voltmeter is still below 14 volts. Making me think that the grid heater is staying on. Makes no difference if its the 1st start of the day or the after driving around all day.

On my buddy 05, the light comes on for about two seconds and then turns off.

I swapped out the IAT sensor (the one by the air filter), same thing.

The CE light came on last night (its since gone off), p0111, p0113 and p0236The truck also smokes like a 12valve when you take off from a stoplight.

What ya guys think? Btw its got 107K miles.

Billy Ram

I would disconect and take out the cables going between the relays and the grid heaters. I don't believe they do much good for cold starting and are battery killers.
Billy

AH64ID

That sounds more like a bandaid than a fix. I notice a big difference on mine, when it gets cold.

I would suspect your getting faulty readings to the ECM. Based on the grid heater and the smoke I would guess the MAP sensor is the culprit.

Smkn600CTD

That the one in the manifold right?

Wonder if the mp8 could be causing this?

AH64ID

Its possible.. unplug for troubleshooting.

LeonT

If it's the heater cycling I think you would be able to hear it clicking on and off. I know I can hear mine in the winter. Turn your headlights on and stand outside to see if they are cycling dim to bright.

That is a strange deal though. Maybe it's something to do with Vegas? I stay away from that place.

93flatbed

I 2x this, Have kicked mine in 0* only hits on 2-3 holes for a minuite or so. But goes just fine after that. They have a small restriction in air flow also. No need for them in my and many many others opinion. I see one guy with another opinion but that's why america is great. Not so much telling someone else that is a "bandaid" but I guess telling people off is ok too?

AH64ID

Yes many people remove them with good luck, I am not saying that there aren't good results w/out one.. I was simply saying I can see a difference in the winter when I let mine cycle. And I would much rather have my engine firing on all 6 right away than gain a few hp...

And yes it is a bandaid, the OP has a problem. The grid heater should not be cycling, so why remove the heater when his ECM is getting an improper signal.. fix that issue.. because that issue will still be there with the GH removed...

93flatbed

I'm not tryin to **** on your boots or anything was just sayin. And I could care less about making a couple of HP by deleating something, I live in AZ a heater grid is just a battery drain to me, the couple of times I go up north hunting is the only time they would ever cycle anyways. You may need it, I see your location is hidden to the public, so I don't know your winters compaired to mine. And not to get in an Argument or anything, but it would be more like a skin graft, it can't controll something that isn't there, and has no other function besides that of warming up some cool air!

AH64ID

Hmm.. my location (Boise, Id) didn't use to be hidden???

Right.. but the root of the problem is still a bad signal, what is causing that, and what else is it messing with (the ECM probably thinks the intake air is below 66*F, which is why he is getting excessive smoke now too)...

Billy Ram

The grid heaters draw 120 amps! That's hard on batterys and alternators. Arround here you just don't need them or block heaters.
Billy

93flatbed

Maybe, don't know, I don't have a PCM/ECM,BCM, or any other things you boys have to worry about, Ive got an Igniton switch, a IPC, a DIC, and three shifters, and I'm happy with that! And the excessive some could be a good thing, the engine is tryin to warm up and is dumping a bunch of fuel to get it there, Head down to the dyno smkn600, I would think you'd make a couple more colts to the wheels.
That was a joke by the way! And what was with the dig on the 12valves. I don't thing the IAT sensor is the one that is used to control the grids, I do blelive it in your intake some where. Yes the pcm is seeing that the truck is cold. Trick it! find out the ohm resistances for differant temp ranges and put a resistor in line so the truck thinks it's always at lets say.....85*. Problem solved and the heater grids could be a nice paper weight, on your desk at work.

AH64ID

Its actually closer to 200 amps... my batteries are almost 5 years old.. no issues yet. Dodge has had grid heaters since 89, its about the only thing in common with a 89 and a 09.. they are a good unit and not prone to failure or causing failures.. just more restrictive (thou I wouldn't want glowplugs)

The way the grid heaters work on a 3rd gen is if the manifold (MAP) sensor say the IAT is below 66* they cycle. The length of cycle depends on IAT and ambient temp. But once the enigne is running they cycle for 2 minutes or until you hit 18mph.

So with knowing that his ECM is probably, this is my guess, seeing temps in the manifold less than 66*, so this will also effect his fuel map..

Fix the issue, then delete if you want.

93flatbed

I lost you on that second one? You are sayin the MAP is reading the temp of the intake and compairing it to the IAT?

AH64ID

The ECM looks at both temperatures but the MAP is the one it uses for the grid heaters (why the OP had no luck replacing the IAT sensor). From what I can tell the IAT sensor (in the intake pre turbo) is mainly used to sense ambient pressure to compare to MAP pressure. the MAP temp is the temp used for the fuel map (all that fancy computer stuff).