Engine/Transmission (1998.5 - 2002) Harder Cold Starts than in past.

[gtwitch]

In the last month here and near to Laramie, My 99 2500 (220 k miles) has been harder starting than in past years at around 0 F on the mountain when not plugged in, has new (October) batteries and cranks well and the wait light is operating (have not checked both elements or relays yet). Yesterday, a construction friend suggested while I was on the 5th pre-start cycle at 0 F that might look at replacing the injectors as they are origional.
Any input here--- thanks.
gtwitch in wyoming.

 

[phantomusa]

You mite have a air leak into your fuel system "lost of fuel prime" i had that problem too took multiple times to bring my system prime up I found my # 4 injector line was bad causing me to loose prime
Pappy

 

[DonFitzwater]

Original injection pump? Have you checked lift pump pressure? Test your grid heater and relays because if one element is burned out, it'll get difficult to start that cold.

 

[Bob4x4]

All of your systems will have degraded to some degree in 220k.Testing will narrow it down if you put in the work
.

 

[KATOOM]

There are a few things which can cause a cold engine hard start issue. 1) A fuel leak allowing the fuel line prime to be lost over the time its not running. 2) Poor injector condition preventing proper fuel atomization. 3) Grid heater elements arent working correctly. 4) Faulty CPS. 5) Slow cranking from unknown bad battery condition. 6) Slow cranking from worn out replacement parts store starter. 7) Loss of compression from damage or wear.
Those are the most common reasons.....

 

[gtwitch]

I have new batteries Oct 2016 , Do not know how to test injectors for leak down , Primary fuel not leaking down ( had and solved that issue couple of years ago , but will ck that again. Frame mounted Holley Blue 14 psi.
and will get to grid heaters/relays soon!
gtwitch in wyoming

 

[DenverPilot]

I have new batteries Oct 2016 , Do not know how to test injectors for leak down , Primary fuel not leaking down ( had and solved that issue couple of years ago , but will ck that again. Frame mounted Holley Blue 14 psi.
and will get to grid heaters/relays soon!
gtwitch in wyoming

When you say "get to" grid heaters and relays, do you mean to test them or to replace them?

In most of the old trucks it's easy to tell if they're working, they draw a lot of current. Turn on the headlights and the heater fan on high and if you don't hear the heater fan cycling down a bit in RPM every so often after start until the engine comes up to temp, they're not drawing any current. You'll also see it in the headlights (they'll dim a little$) and as about a volt or so change in the voltmeter as they cycle on and off. Even on a good battery and charging system.

 

[gtwitch]

Yes I will test those relays and both heaters, but injector pump is Blue Chip only 4 years old and I am suspecting injectors as they are origional and 18 years old with 223K miles.!
gtwitch in wyoming

 

[JR]

while I was on the 5th pre-start cycle at 0 F.

Do you mean you cycle your grids that many times? I've never had the need to do that, the grid heater duration should be staying on based on temp, cycling them that many times is very likely taking alot of reserve out of the batteries.

As long as you've ran nothing but reasonably filtered fuel through your injectors (no used motoroil, Homebrew bio, etc) I wouldn't necessarily expect them to be worn at 220k miles. I've seen 2nd gen injectors with well over 300k miles. My former 00 had 380k miles on its original injectors when I sold it although there was a noticable haze at cold start up. I believe they were due for replacement.