Engine/Transmission (1994 - 1998) Hard cold weather starts

[corprimo]

The last few months my '97 has been starting harder when I can't plug it in - below freezing temps. It will fire, quit, fire quit, give it more fuel, fire a bit longer, quit, finally starts, but runs very rough for a few minutes, lots of smoke. If I can plug it in, it starts fine. Once it's warmed up, it's fine. Ammeter shows heater grids are working. Suggestions?

 

[DSiemens]

Could be a leak in either the fuel supply or return lines. Kind of a pain to change. One is 3/8 and the other is 5/16 I believe. If I am wrong others will post with the correct size. A search will yield a lot of info.

 

[corprimo]

How would outside temp. affect the fuel line leak. Wouldn't I get the same hard starting if engine was plugged in or garaged if it was a leaking fuel line?

 

[DSiemens]

So when the truck is plugged in, you don't have any problem starting? If so, then the only two things I can think of is a slow idle speed and timing. What happens when the truck is cold and you lightly press on the go peddle while cranking.

 

[corprimo]

Truck fires right up if plugged in or garaged. But if left out with no plug in - temps in teens or so, it's hard starting. Idle is up to specs (higher than I like it with the auto. Trans), and once it's run for a few minutes, it runs fine. Are their two grid heaters? Maybe one of them is burned out...

 

[DSiemens]

Yes, there are two grid heaters.

 

[Cooker]

This has been discussed a few times over the last few years



Here is a list of things to check some have already been mentioned:



-idle speed

-fuel filter

-all battery connections, especially the blue wire on the drivers side battery

-all connections on the grid heater solenoids

-make sure the fuel shutdown solenoid is pulling all the way up when cold

-proper opeation of the grid heaters

-timing (not as likely as some of the other things)



Have you done anything over the past summer to increase fueling such as a plate?



These are a few things that come to mind off the top of my head?



You might try a search, there will be a ton of info on this topic.

 

[Missouri Mule]

How about the fuel heater not doing its job as well as it should.



Blowing smoke and not wanting to run sure sounds like grid heaters. (especially white)

Is your grid heaters working in post cycle.



Two connectors (hot ) for grid heaters, looks like grounds the for heaters are opposite hot connections. Two small nuts/bolts attached to plate at bottom of heater housing.

 

[Cooker]

Originally posted by Missouri Mule

How about the fuel heater not doing its job as well as it should.

This doesn't really cause any problems until it's gets real cold, ie. well below zero.

 

[JJW_ND]

Timing and.or Grids

The lack of grid heater start to cause the effects you speak of in the teens and lower. Most wont start at all below -5.



Watch your volt meter when starting, it should peg the neddle below 11 when you first turn the key and wait to start. You should here the solinoid click (snap) when it releases and it is time to start (your volt gauge should rise. Onces started you should see your volt gauge cycle up and down ... . hugh drop with each cycle.



Timing also, helps some but mostly how it runs after started.



jjw

ND

 

[corprimo]

Thanks for all the input. Voltage fluctuation indicates that the grid heaters, are working, but I'm thinking it may just be one of them. That would account for the rough running when it does start. I'll have to do some testing to figure out for sure, but it's going to have to wait a while because we're flying down to Portland later tonight on a red eye to go visit our son. I'll have to get out the shop manual when I get back and see what's what! Lately I've been plugging it in, but last night a friend got stuck on our icy driveway, needed a tow, and I didn't have the truck plugged in and didn't have time to let it warm up more than a minute, and it was really running rough!

 

[Rhondasway]

I'd like to know what you discover on this, as my truck does exactly the same thing... Very hard to start even with temps in the 40's if not plugged in. Turns over very strong, but when it finally catches it runs real rough at first. Plugged in it starts and runs perfectly... .

How can the grid heaters be tested?

 

[Dennis Garrett]

Don't trust the Ammeter fluctuations, you will see cycling even if one grid heater is not working. It takes BOTH heaters working for a cold start. Follow both leads back from your manifold heaters & you will find two relays on a common bracket on the fender well. They have to be replaced as a set for about $65 bucks. They are connected directly to the battery. Have somebody turn the switch "on" but don't start, with a voltage tester, make sure you are getting voltage to BOTH grids by checking at either the grid side of the relays or at the grid connections. Also make sure all the nuts are tight on all the cables, they seem to work loose over time.

 

[mainer]

The owner's manual says when it's cold out you should slightly depress the pedal as you turn it over. I know this makes a big difference on mine, and starts easily that way in cold weather.

 

[JGheen]

What about fuel gelling?? Have you looked into that happening?? I had a similar issue when I lived in Durango, CO and my fuel gelled up a bit when I didn't plug it in on a VERY cold night and it ran extremely rough until it warmed up. I took a hair drier to the fuel tank a couple of times, took a long time to get it somewhat warm , but that seemed to help. I doubt you have a leak in your fuel lines anywhere since you said it runs fine when it is warm. Plus, I am sure you check under the truck once in a while to see if anything is leaking more than normal, such as typical oil leaks from these engines, at least I do.