engine revs up and down when cold?
 

cranks fine, starts fine but it just revs up and down, i'd say up to 1200 or 1400 rpm down to about dying then it finally does die.my 95 has always started fine, but my new to me 01 the last 2 days, has been giving me fits. yestereday it died 2 times before stabilizing rpm. havent plugged in either truck yet this year as its only been around 30 degrees at in the morning. just can't afford to let me sit so wondering if this is normal for an 01 or i should check something???

when it revs up and down, does it do it fast or kind slow? it shouldn't be doing this unless the PCM kicks on the high idle. but even then it will raise to a certain RPM and hold it there. do you have any way to check for codes?

i do have a way to check for codes, hasn't been any but i haven't checked in a couple weeks...it sounds like a cammed up blown alcohol engine that has way to much fuel going into it at idle! (sorry, i'm a drag racer and thats the only think i can compare it to!, just real lopey if that makes sense, ....when it does stabilize, in a minute or 2 the fast idle will kick in. the last 2 mornings is the only time the fast idle has ever kicked in, so i'm assuming it only does this when its REALLy cold???

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and it spikes up to 1200rpm or so,(maybe a little higher) quickly, then drops to below idle. and repeats this until it either A. dies and i restart the truck. or B. idle stabilizes, then i a couple minutes the fast idle kicks in and i let it warm up and away we go! truck running great, no other issues...

well it made sense to me. do you have flames coming out of your exhaust too? LOL. and it has only done this with it being cold? how many miles are on the truck? what weight of oil are you running? any smoke when it lopes?

61k when i got it 3months ago, and 92k on it now! 15w40 rottella. just changed it saturday. i didn't see any crazy bad smoke like my 95 does when it cold, but it did seem to be smoking some when it was loping like they do when there cold. today it started just fine, no lope at all and i figured it was just as cold today as the last 2 mornings...only flames come out when i'm really heavy!!!

61 k?? dam that's low. i thought i hit a jackpot on my 99. 138k. it could be a high pressure oil problem. did checking for codes say anything? maybe the IPR is plugged. there is a thread on here on how to clean it. dam that must be really heavy to do that! hey it keeps people out of your blind spots. lol

yeah, and if i told you what i paid for it you'd want to hunt me down b/c you'd think i stole it! i'd buy another for that price, but i know that won't ever happen again...the fuel element heater sensor (i'm assuming thats what it is) wires are showing and i'm going to rewire it tomorrow. idk if that would cause it, but actually it hasn';t done it all dam week, just those 2 days last week! btw, my 95 had 120k on it until 8 months ago until i put it to work and now has 170k..

you can tell me. i wouldn't go all the way to PA. Lol. the fuel heater shouldn't cause that but you definitly need to get that fixed. well i got my 99 at the end of january this year with 138. now it's got 155. but you probably put on 400 miles a day. before i got this the 99 i found a 01 with 73k and a 03 with 67k. but the dealers wanted over 20k and they booked out for about 17k. it was just barely out of my budget. still kicking myself for that. then my old 96, i put on about 45k in a year and a half.

[QUOTE=fordornothing;816939]you can tell me. i wouldn't go all the way to PA. Lol. the fuel heater shouldn't cause that but you definitly need to get that fixed. well i got my 99 at the end of january this year with 138. now it's got 155. but you probably put on 400 miles a day. before i got this the 99 i found a 01 with 73k and a 03 with 67k. but the dealers wanted over 20k and they booked out for about 17k. it was just barely out of my budget. still kicking myself for that. then my old 96, i put on about 45k in a year and a half.[/QUOT

yeah, everyday is different. i've run as much as 1100miles a day, but i been staying busy and averaging around 500-600 a day, 5 days a week with my 01.

i tested the glow plug relay, and it wasn't working so i put a new one on yesterday and now it is! man, that thing really hums compared to the 95 when the glow plugs are activated(i tested the 95 too just to make sure they were working, they are). so i hope this fixes my deal, and i taped up the bare wires on the fuel heater so i believe that is all good. is the intake heater set by a thermostat or something? i tested that relay with key on when it cooled down last night and it wasn't working either. might just get a new relay too.

From what I have read the intake air heater is to help keep them from smoking in cold weather long idling situations. A lot of people delete it altogether. It doesn't sound like you do much idling with the number of miles you drive. I wouldn't worry about that system.