• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

Hard starting in cold weather with 98/95 merge

Unfortunately everyone has been confused and you removed the pertinent info from the first posts. I have been trying to point out he does not have any starting issues, its a bad idle issue after startup, but have been contradicted on symantics of poor performance after startup and warm up idle issue.

Quote from his original post
First thing in the morning. glow,start [very quik], instant fireup on all 8. 1 sec later engine falls back to very low idle,starts bucking and smoking bad. And has NO pedal control left [dead] This goes on for 1 to 5 min depending on ambient temp. the colder the longer it takes.then engine comes suddenly back to life ,smooth running and pedal control is back. then truck starts and runs fine all day.

Another question....
Is this the same vehicle you wired up the high idle with 12V instead of ground? And you have the remote start on?[/QUOtE

Nope, the 95 did not have high idle or remote start(it was bone stock),high idle and remote start is in the 98.now before you point fingers.The high idle has been corrected and it works fine now. Aplying 12 v to 12 volt apparently did not cause harm to the PCM
second:the symtom described is identical to the symtom experienced in the 95 wich donated the IP and the engine.
third: i did not delete the first batch of posts, Turbine Doc did cause he felt it was confusing,and transported the rest to this tread
 
Last edited:
I wasnt pointing fingers, just saying how people got to this state of confusion, because someone must have mistook your issue with someone elses and confused everyone else, and your responses werent helping, especially after agreeing when they said things like you have a cold starting issue.

So this issue was there as soon as you put the engine in, and you noticed the issue before messing with the high idle circuit? Did you do the high idle circuit mod when it was in the 95?
 
Just looked in the book and if you want to jump the coolant temp sensor harness with resistor it should be more like 300 ohms to be about 180F, or around 500ohms would be around 150F.
 
Unfortunately everyone has been confused and you removed the pertinent info from the first posts. I have been trying to point out he does not have any starting issues, its a bad idle issue after startup, but have been contradicted on symantics of poor performance after startup and warm up idle issue.

Quote from his original post
First thing in the morning. glow,start [very quik], instant fireup on all 8. 1 sec later engine falls back to very low idle,starts bucking and smoking bad. And has NO pedal control left [dead] This goes on for 1 to 5 min depending on ambient temp. the colder the longer it takes.then engine comes suddenly back to life ,smooth running and pedal control is back. then truck starts and runs fine all day.

Another question....
Is this the same vehicle you wired up the high idle with 12V instead of ground? And you have the remote start on?

The stuff that was deleted was what was occurring in June 08 on a 95 truck and not germaine now to the 98 transplant, I was not trying to solve anything necessarily since everybody was going different directions I was trying to bring the diagnostic train of thought back on track mostly just trying to lay foundation of information of what is happening now. I asked if I had left anything out which in post 18/46 above he confirmed as a starting issue and then you interjected opionion on diagnostics from the 95s problem.

With total disregard to what happened in June 08, lets go at this with fresh perspective to cleanout the cobwebs.

Bison describe the issue, is it that you are not able to get the truck to start, or as Buddy was indicating that once it is actually started it is having difficulties until the engine warms up a little, those are 2 different scenarios.

That exactly sums it up to a T.No isuess what so ever but that one.
I got an IP i took apart,they are actually pretty simple mechanicly. And other than a electr gremlin in the FS,OS or stepper motor, the only thing I can think of would be a sticking advance part or the FS valve itself.If this condition (very low rough idle without the rattle and blue/black smoke) is limp mode? It should trow a code right? Yet it does not.
This is not the IP on the truck now is it???

In my very first post, when the engine was still in the 95 i mentioned that there was no trottle response asociated with the start up idle problem.

At that time i suspected the glow circuit.I put in new AC delco 60-g plugs,measured 12 volt on all leads.It made No diff. mind you the engine would fire up instantly in -30 with blockheater of course. Without operational glow system it would have never started.
Next I swapped the AAP for a known good one.Still no dif

fast forward.
Gremlin followed the truck

Glow controller performs good.all leads are verified good,(checked with DVM)the plugs where used for only a week(i considder them new) and a glow bypass switch to extend the glow time on the slowerheating 60-G in our cold winter climate is installed as well + a fuel gauge..At overhaul, i tested all the glowplugs on the batt for working before installing them again. 2 brandnew 1050 amp batts installed.Cranking is very fast
The engine actually starts on all 8 immiddiatly but falls back to the slow irregulair idle within a sec.Then it is barely making 400 rpm on the tach.At that point there is no pedal response.
I did not check for volt drop but the amp gauge drops from 14.5 volt to 13 volt when ever the wait to start light lits up. (normal as glows energize)

I dont know what to add.
Confirm the following summary is accurate, the situation is now; good cranking & glow system is correct, your truck starts fine but fails to idle properly in very cold weather, but once the engine warms up then it responds properly, in warm weather you do not have this issue is that correct? (what temps are you calling warm ?) when in this cold weather situation until your engine warms up you have no throttle authority via APP (and this is a cold weather anomaly only correct?).

You did the engine transplant and it works fine most days, I now think you have same IP on the engine as it had when it was installed in the 95 (what is the model # of that IP), you have not moved the IP from it's timed position that works fine once truck is warmed & running, when it starts then cuts back does the engine ever acheive normal idle (when warm, for your truck what rpm is that), or does it come just below your normal idle then cut back to a sub idle until the engine warms up, if that what rpm does it cut back to?

When idling with no APP control do you have a lot of whitish heavy fuel smelling smoke from exhaust? With cold weather you are plugging in the block heater-is it still working ???, is your heating element in the filter manager working?

Buddy please step away from the keyboard :D that is what I'm going to do for a while, I have some thoughts what it could be, but I want as much additional (without my/our opinion biases) info Bison can provide, before offering any more suggestions just yet.

Bison I want to know exactly what YOU are seeing Bison, and correct all missed points as to what is occurring now disregarding what was said in or done since June 08, our ability to trouble shoot remotely is soley based on what you report, you are the eyes and ears here, describe as best you can any differences in rpm-temp-smoke-speed-sounds-etc between the warm weather and cold weather starting.
 
Last edited:
I dont realy know what causes all the confusion,cause i thought i had covered every thing. But i try again.
TD latest post ,describe the issue.

A 95 engine transplanted to a 98 truck.
Engine starts and runs well at ambient temps around 0 celsius and up.No issues what so ever.No smoke from the tail pipe, very clean running.
First start on outside overnight mornings temps -10 to -20 c observed ,1 block heater plugged in( it got 2 new block heaters) After running glow cycle, a turn of the key and the engine fires up immidiatly on all 8 but falls back within a sec to a eratic subidle ( around 400 rpm)and a fair amount of grey/blue/black smoke from the tail pipe.At these times there is no APP control(dead}Check engine light flashes briefly only once.Fuel pressure 6 psi.
This subidle continues for 1 to a couple of min(varies with temps) till all of a sudden the engine smooths out and the rattle appeares, idle increases to Around 950 rpm on the tach and APP control is back.the smoke disapears as well. After warm up for a few min the idle cuts back to 600/650 rpm.Normal on this truck from the get go.

This subidle to 950 rpm idle is instant ,and not as if diff cylinders come online 1 0r 2 at the time.

The IP I disassembled is NOT the IP from this engine.

question 1)Yes, cold weather problem only (sofar)

2) Latest blue tag IP #5521. RPM patern is decribed above. Warm to me is right now around 0 celsius:D Its still winter here

3) No white smoke, mixture of dark grey/blue/black. New Block heater,and working.I dont know if the Fuel heater is working,I did not check it.
No codes ever found with OBDll scanner.

No other anomalities to report

The only electrical from the 95 transplanted engine is the IP.

I now need to get a new FSD, cause as of last night i had to transplant the 98 FSD to my wifes 95 truck as its gave up the ghost when she was coming home.:mad2:
 
Last edited:
Update,

I tested the fuel heater,took it of the filter, left it out side overnight,tested with 12 v aplied for heating up this morning.it works.
I also left a cup of the fuel outside overnight too (it was -30 C this morning) No gelling observed.
 
OK, let's bump this back to the top, Bison.

I'm feeling a little frazzled with this one, too many things being tossed around at once, so bear with me (pun intended) while I slow down and get specific.

It's been my experience that when any number of things can be the problem, you go with Occam's Razor - that's another way of saying that the simplest and most obvious thing is probably the cause, and looking for something esoteric first is just clouding the problem. So let's try that, shall we?

Besides, most of the time, you're better off starting with the cheap and easy stuff, not the expensive and hard stuff.

The situation: you put a new engine (that you rebuilt yourself) into this 1998 truck. The IP is a 5521, the glows are good, the PCM is OBD-2, and the engine hasn't been timed or had a TDCO set, but it starts and runs good. If it's warm, kept inside. If it starts when cold (outside), it drops idle below control threshold, runs like crap and has no throttle response. Once it warms up, then things are all good again.

That about cover it?

OK, here's my thinking... these damn trucks don't fix themselves. If you had a problem with wiring, theft-deterrent, throttle rheostat, brakes, windshield-washer, etc, the problem would be there all the time. That (and Occam's Razor) tells me your issue probably isn't any of those things. It also tells me that the only thing changing here is the temperature when starting - once the engine warms up, it's all good.

If your IP was shot, the problem wouldn't fix itself. If your PMD was dead, the problem wouldn't be so regular, but would be erratic. If the PCM was broke, temperature wouldn't be the determining factor.

So... I look for something that changes when it's cold. Said something somehow puts the truck off its feed, makes the idle really low and tells the PCM to ignore input from the APP.

Puts me right back at the beginning; timing. When your truck is cold (CTS), the PCM advances the timing. When it warms up, the timing comes back to hard settings. What would be the effect of advancing the timing out of range? See, that would happen if the truck was too far advanced to start with, no?

Humour me, OK? Scribe your IP, loosen it, turn it 1-2 mm toward pass. side, tighten it back down, and try starting truck cold. Worst case is, you have to put it back where you found it.
 
Last edited:
I was waiting for TD to post again but I read something that it thought had merit. The article was on a gear drive installation. Anyway one of the things it mentioned was that one of the things that this install fixed was a stumble when it was started cold. Which was cured by improving the timing. I would think that due to manufacturing tolerances that if you didn't do a TDCO that the timing would be off a little bit and maybe thats enough to cause your problem. I had my IP out last summer and when I put it back I didn't do a TDCO because it ran so well. But when cold weather came it started to act up exactly as you decribed. I'm getting ready to put a gear drive in my truck and do a TDCO. We'll see what happens.
 
I been doing some reading and thinking also,snooping trough AllData. Gawd,the electricals are complicated in these OBDll vehicles,adding in the passlock system to that makes for total chaos to me.

I hear you guys, I came to that conclusion too. I did a VIN check on the (old 95),turned out the IP was not dealer replaced,so tdc learn may never have been done on it.
Only thing that baffles me is why dont it set any codes??

Without a proper scanner, one seems to be lost on these things. So,autoinguinity is on order. i have to wait for it and a new FSD to arrive before i can do anything.
I wish i had bought a Tford instead!
 
Still wondering about possible problem with ect sensor not giving correct info to pcm in very cold conditions & not calling for advance & high idle.
Would only take a second to unhook sensor to get pcm to default to -40 & see what happens.(on a cold Peace River day). Could check to see if stepper motor is advancing or able to advance at same time .Chicken hunter is weighing in on what seems to be a similar prob on the other forum .
 
Still wondering about possible problem with ect sensor not giving correct info to pcm in very cold conditions & not calling for advance & high idle.
Would only take a second to unhook sensor to get pcm to default to -40 & see what happens.(on a cold Peace River day). Could check to see if stepper motor is advancing or able to advance at same time .Chicken hunter is weighing in on what seems to be a similar prob on the other forum .
tried that trick allready,there no friggin way to observe the stepper motor without removing things.
I need to check the timing first.
 
Maybe pump is positioned ( retarded )enough that stepper cant travel ( advance) enough to adjust for real cold temps .Maybe maybe maybe .
No disagreement on the need for a time check. My pump was changed awhile back & the way truck starts now (not as clean & more time on starter) makes me wonder about timing .
 
BumpToTop

TD, any ideas.....you said you were thinking about it........As well as many other things I'm sure.........Sorry if that didn't sound right.


Thanks,
 
No,G'dam mail is slower than shit trough a funnel,its been 14 days tommorow.I could set the pump a couple degree back, but it wont tell me much now the weather is warmer.

i like to see with the scanner what the actual timing is before farting with it.
 
Yeah, well, just make sure you follow through on this one, Pal... once it gets warmer, your symptoms may disappear until next fall and you'll be starting all over trying to figure it out!
 
bison i have a simular prob only my dead pedal is when i put it in drive or reverse. I am getting a code 35 optical sensor. my two cents is that there is a problem not big enough to code with your optical sensor or your fuel selonid is hanging in the cold temps.
The reason i believe this is because these two parts are the only thing that did not change between trucks (right).
 
right, but you seem to only a dead pedal while shifting.that looks to be a diff can of worms. Ahh, dont you just admire these electronics
 
Yeah, well, just make sure you follow through on this one, Pal... once it gets warmer, your symptoms may disappear until next fall and you'll be starting all over trying to figure it out!
dont worry buddy,i'll get this figured out one way or another.
I'll keep it posted.
 
Back
Top