ChrisM510

My dad has a 1997 S10 2.2L pickup (88,000 miles) that is having starting problems. The problem only presents itself when the vehicle has sat for a few hours (6+ hours or more) and the weather outside is damp/moist/clammy. Never happens when it is really warm out or when it is really cold out.... The engine will crank and crank but just won't start. If you let it set for a bit (15 minutes to a half hour or so) it will start right up like there was never a problem. We have replaced the fuel filter, spark plugs, plug wires, battery, O2 sensor, mass airflow sensor, air filter, and have had it into a repair shop to hook it up to the diagnostic computer....no luck. This problem doesn't happen on every damp/moist/clammy day/night, but it only ever happens when the weather is like that.

Any ideas? We're hoping its a sensor or something relatively easy to replace before the weather starts turning bad again.

Thanks in advance for any help...

cglenn2a

yikes. I hope you pin it down, because I have not been able to. I have an 89 S-15 4.3 TBI and every time the weather is damp, and cooler it runs like a bag of buttholes. It gets a really fuel rich mixture, ehxaust goes black, idles high, then stalls from choking too much. I think i have replaced every sensor that i know of, and no results.
I wish you patience and good help.

Mikado14

Every time I have run into this, I have pulled the cap and saw the stellagtites growing. When was the last time you did a tune-up?

Walker S-10

yea i good tuneup would probly fix your problem

ChrisM510

What part of a tune-up could we have missed? As I said, we changed out the spark plugs, spark plug wires, fuel filter, O2 sensor, etc. We have also changed out the PCV valve.

At first I thought it might be the fuel pump because when it is exhibiting the problem, it acts just like a car that let the gas tank go empty.....but after waiting a while it is fine, so that kinda shoots a hole in the idea that its the pump (though this is not a definitive test for a bad fuel pump).

Thanks again for the replies...hopefully someone out there has the key solution...

BlazerLT

You have done the tuneup and are fine.

Sounds like a fuel pump to me bro.

Fireplug

REPLACE THE DIST CAP. Very easy fix Have seen about a billion of these problems.
Make sure you get the dist cap on the correct way its easy to get it on twisted.
The clue is DAMP Weather.
The cap wickes water vaper into it then its hard to start when cold and damp.
Fireplug
Retired GM Master Tech
Ase Mster Tech

ChrisM510

I think this engine has the DIS (distributorless ignition system)...what would be the equivalent part to replace?

Fireplug

Ok I see 97 that year did come both ways early had a cap and late did not.

Where did you plug the ign wires into a cap or coils

ChrisM510

I'll have to check....my dad did the wires.

BTW...thanks!

BlazerLT

I would stull remove the bed and check out the fual pump.

Fireplug

If you have the coil pack type take spray bottle and use a mist spray and spray the coil pack while the engine is running and check for any arcing also put the engine under load and redo it. Put it in gear and foot on brake , e-brake on and block the wheels raise the engine rpm to about 2,000 to 2500 rpm and check for arcing while misting the coil pack.
This is a poor mans engine scope do in most shops because they will not pay big money for a good scope
Fireplug

BlazerLT

Ah, good point.

ChrisM510

Thanks! I will give that a try and reply back with my results...

Ones&zeros

check your coil packs.those packs tend to get sensitive to any weather. next time the car dosnt want to start check if your spark plug wires are geting any sparks. take off spark plug wire from spark plug, stik in screw driver in it, and put close to body, !! but dont touch body!! when cranking you should see an ark..