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Last time I forget to plug in...

2K views 17 replies 10 participants last post by  99redgtp 
#1 ·
It was about 27 when I went to start this morning, let it sit with the key on for 20 seconds then cranked (my wait to start light didn't get rewired in the cab swap I guess) but it cranked for a while, fired then died immediately. Reapeated that two more times then I hopped in and gave it some throttle and cranked again. It fired and ran worse than it ever has, and smoked more white than i've ever seen come from a tailpipe. It was idling really low, but it usually does that for a minute after starting. After a few minutes the white went away, but it was still smoking blue, which it hasn't done before. The blue smoke stopped when I started driving.

So my questions, this isn't normal for a 12v is it? I know they're start hard in the morning but that was rediculous. If there's something wrong I'd like to fix it incase I forget to plug in again. Starts fine when it's plugged in or warm.
 
#3 ·
My 12V cranked right over at -28C after 2 cycles of the intake heater....27F....it should start immediately.
Check your intake grid heater, maybe? Also your fuel.
 
#6 ·
I just had an unusual clouds of white smoke spewing out on cold starts ups ( temp in the 20's). I knew something was wrong. Found one grid not working. Even so, with a little pedal, it still fired up quick.
 
#7 ·
My grid heaters were cycling tonight after work so they're working. It sat out for about 7 hours there, cranked for a few seconds and then started up, ran at say 200rpm and gradually increased up to about 800 over 2 minutes, which is what it's always done when cold. This morning was just way worse than normal.
 
#8 ·
Are you sure both are working? I had one to go out on the 97 due to a bad relay. It was hard to start at 20. I have a 0.020 marine head gasket though. Before that I didn't even let them cycle unless it was below 20 f. It always fired right up. The old 93 still fires right up barely turning over even when cold. And it only has 1 battery that was bought in 2002.
 
#11 ·
Yes!

I had one relay go out and it was very noticable when it got in the 20's.

Also if you look at them when they kick on it is evedent how much less heat would be put into the intake.

This is what they should look like:
 
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#14 · (Edited)
What happens is the computer allows only 30 sec max heat up time and then it cuts the power to the heater grids, so they start to fade. I believe this picture was taken on a second cycle of the heater grid. Using the key to set off the heater grid there is no way to make it go more than 30 sec, that I am aware of....

Also, the camera is probably excentuating the glow...

Both heating grids are on in this pic.
 
#16 ·
Depending on the shot mine might appear like that with flash at the end of the first cycle...
 
#18 ·
you could just check for voltage at the terminals where the wires hook on. that will tell you if you have a bad relay which is what will likely went bad. I dont remember exactly when i tested mine but you should have voltage on both terminals when you touch a ground and a terminal. they both kick on until the wait to start light goes out then the pcm flashes them one at a time if I remeber correctly. my truck sat for a week in this 10* weather we've been having and after 2 cycles of the grid heaters fired right up.
 
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