Surging idle on cold start

[PlayingWithTBI]

I think on gear head-ef, and found some guy explaining how to make your own for something like $10. But for me, the time to find the parts and then dealing my lousy electronics build/solder reliability when I’m already frustrated trying to fix something on the truck — it just wasn’t worth the time or aggravation

Yes, and if you have a hard time connecting, you won't know if you did something wrong building the cable or how you configured TP and your device manager. At least this way, you've eliminated the cable issue.

 

[thinger2]

your air cleaner doesn't have the flapper schurkey is talking about?
i assume you plugged any vac lines if needed.
Thinger says his 94 doesn't have the flapper, just the tube from the exhaust manifold, my 95 has both.
if it ever stops raining i'll take a pic and test mine.

I havent verified that it doesnt have it yet.
Im neck deep in storm damage.
But, I dont think it does.
Not that it didnt have one to begin with.
But Im pretty sure It aint around anymore.
However, I am the 3rd owner of this truck and I started doing the work on it for the 2nd owner before I bought it because he had done nutty things to it.
Like putting new wires on it and zip tying the slack to the exhaust.
Then he tried to patch them with blue masking tape.
Cuz it was more expensive and better than regular masking tape.
Who knows what happened.
But I had no trouble for the first 10 years or so.
The thing that did change is for the last two winters.
Which is the only time Ive had this problem, Ive parked the truck in a spot that never sees the sun.
I am starting to think that it is missing the flapper valve and that Schurkey is right about carb iceing.
And I think carb iceing takes on a somewhat different form with a TBI.
Cold sensors, cold manifold, cold throttebody etc..
Worn out this and worn out that
Any combination might just be beyond what the ecm uses for normal start which triggers something to rich flood it?
Thats way beyond my tech knowledge.
But I do know this.
If my Nissans did the same thing I would instantly foul the plugs and the timing chain would rip the plastic guides apart and start digging a hole through the front cover.
Thats a bit of an involved repair.
The VW would just refuse to start and light up like Times Square on New Years eve.

The truck just needs me to give it about 25 percent of the foot and onions for about a minute and shes good to go.
Its cold any wet and windy as hell.
I will stick a new set of plugs in the Chevy every month if i have too before I will deal with any outside in the rain tree limb blowing ******** for the other cars.

 

[thinger2]

My '88 was first-year of the GMT400. Service manual has a copyright date of '86.

The service manual has so many mistakes and bad info that they had to publish a "Service Manual Suppliment" to correct most of them.

Yep. Look at how much information survives in a Chilton Or Haynes book.
The intro guides are ancient nonsense
It doesnt surprise me at all that people get into trouble from buying these things.
Mechanic comic books.
For someone just starting out.
I think those comics may do more harm than good.
Us old guys can sort the ******** because we know that its ********.
Somebody new to the knuckle bleeding combustion arts?
Probably not.
But, There are people who come here because they are trying.
And I think thats awesome.
Now , we get a chance to pass on some knowledge that will never happen unless we do it.
Dont hoard your knowledge and wisdom bud
Give it away

 

[Schurkey]

the knuckle bleeding combustion arts?

Thanks for that.

Instant mental image: Professor Snape, as Defense Against the Dark Arts Instructor, giving lessons in proper use of the Torque Wrench Wand, for warding off evil gasket failures.

 

[PEIslander]

My 94 K3500 5.7 does the exact same thing when cold. Feels like an old carbed vehicle that hasn't had time to warm up properly. I've yet to find the cause.

 

[PlayingWithTBI]

i don't have any issues with mine, even when temps get all the way down in the 40s

 

[EmeraldCityGuy]

But, There are people who come here because they are trying.
And I think thats awesome.
Now , we get a chance to pass on some knowledge that will never happen unless we do it.
Dont hoard your knowledge and wisdom bud
Give it away

Good advise! At 71, I’ve come to the same point. We live in Maple Valley and have had several trees come down on our propert. Winter life in the PNW is never dull.
I own a 92 K2500 454, am having the same stumbling on cold start and trying to figure it out - hence, following this thread.
You’re welcome for a cup coffee anytime!

Rich

 

[1997]

pic's of the AC with flapper, COLD

 

[1997]

pic's of the AC with flapper, held open for pic's and simulating HOT

HOT,

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[thinger2]

Good advise! At 71, I’ve come to the same point. We live in Maple Valley and have had several trees come down on our propert. Winter life in the PNW is never dull.
I own a 92 K2500 454, am having the same stumbling on cold start and trying to figure it out - hence, following this thread.
You’re welcome for a

Thanks for that.

Instant mental image: Professor Snape, as Defense Against the Dark Arts Instructor, giving lessons in proper use of the Torque Wrench Wand, for warding off evil gasket failures.

"Combustion Arts" comes from one of the most bizarre coincidences of my life.
Back in 1986 I worked on the Jacob Javits center in New York.
Met a guy from West Virginia.
Being two rookie pumpkins in the trade we hung out partied way too much and got along great.
Job ended, I went to Florida and he went to Baltimore.
About 32 or so years later I finnally got convinced to go on Facebook.
So Im trying to figure this **** out and look at the friends list of a woman Ive known since high school.
And this guy is on the list.
Turns out that me telling him that the pacific northwest is paradise convinced him.
This guy not only is friends with my old friends, he lives about 10 miles from me.
And has lived here since 1986.
We have been to the same weddings, the same parties, the same funerals
We just never ran into each other.
He coined the term "combustion arts"
What an odd world