New guy /86 B2000 - vapor lock

[brad 454]

Hi all
Nice forum.
I did a search and didn't find what I was looking for. My 86 B2000 has developed a problem since it got warm. The truck has a intermittent hiccup. It started off to be just a little annoyance. Today the truck when it was drove stalled. I am suspecting it is vapor lock. It is 104f out and the problem seems heat related. I am a fairly new owner of the truck and wanted to know if vapor lock is problem with these trucks. Is there a fix? Could the problem be solved with a new FP?
Thanks Brad

[03chevy]

check these out
1Inspect Fuel Filter Clogged or dirty fuel filter

2Inspect Air Filter Restricted or clogged air filter.

3Inspect Wireset Damaged, worn, or deteriorating spark plug or coil wire(s).

4Inspect Carburetor Float Improperly adjusted/saturated or damaged carburetor float.

5Inspect Spark Plug Fouled, damaged or broken spark plug(s).

7Inspect Timing Cover Stud Kit - PerformanceImproperly adjusted or worn/malfunctioning power valve

8Inspect Choke Pulloff Worn, defective, or faulty choke pulloff(s).

9Inspect Choke Thermostat Stuck or improperly functioning choke thermostat.

10Inspect Fuel System Pressure Incorrect fuel pressure being delivered to carburetor or fuel injection system.

11Inspect Spark Plug Wire Loom - Performance Improperly adjusted or worn/malfunctioning carburetor.

12Inspect Hood Brace Leaking, worn, or damaged intake manifold gasket

13Inspect Fuel Injector Plugged, dirty or poorly connected fuel injector.

14Inspect Fuel Pump Improperly functioning fuel pump or circuits.

[brad 454]

Hi thanks for the help. All of the below was replaced less then1200 miles ago
Fuel filter replaced
air cleaner replaced
wire set new
new plugs
new carb
New coil
a different stock dizzy
new ignition control module
Fuel pressure is within specs
I took the truck to the mechanic when the I first couldn't diagnose the problem. He told me it was the dizzy. I got another working dizzy from a friend on another board. That didn't solve the problem. I then replaced the coil and the ICM. Still had the problem. Was going to live with it and then it got worse. Took it back to the mechanic and after 3 hours he couldn't find the exact problem.
He seemed to think there was more then one problem. After 3 hours he wanted to keep it longer ($) and I just couldn't afford it. At this point I am not sure in what direction to turn. I really need the truck. It gets 30 mpg.
Thanks Brad

[Chevy_Finatic79]

so by vapor lock do you mean it just runs until it seems like it run out of gas?

[brad 454]

Yeah sort of. In the beginning I thought the problem was fuel/heat related. You would be driving a long and when you would let off the gas to shift it would stumble or hiccup. It would act like you were running out of gas or the fuel filter was clogged. It seemed at first worse when it was hot outside - over 90 degrees. Then if you worked the throttle it would catch and run along fine. Some times it would take a bit of working before it would go again. Then it would run for a while and do it again. It really didn't ever stall because the truck was still moving. After checking numerous things and not being able to get it corrected, I took it to the mechanic. He said it was the dizzy. I replaced it with a known working unit and as I said above it didn't solve the problem. I worked on it for a while longer replacing the coil and icm. I took it back to the mechanic and explained that his diagnosis was wrong and he rechecked it. He spent about 3 hours and still couldn't determine exactly what was wrong.

That is where it stands now. I initially thought it was fuel related, but the mechanic thought it was ignition/electrical. I am not sure at this point what else to look at.

Thanks Brad

[BlownFX4]

I am having the same problem with my B2600. Did you figure it out?

[brad 454]

Thus far I believe it is the carb. I sent it back to the rebuilder. I will post back when I get it back on the truck.

Thanks Brad

[tommi2tone]

Check and see if your egr is sticking if it is stuck open it will act like vapor lock

[mikeyc1945]

It sounds like you've replaced everything on the ignition system.

Check your fuel pressure. Also, these trucks have problems with rust in the fuel tank. It plugs up the fuel strainer in the tank. When the engine dies, it sloshes enough fuel over the strainer without any draw on it to wash the rust off of it and the cycle starts all over. It gets worse as time goes on.

Also, try spraying carburetor cleaner around the base of the carburetor and around the intake manifold gasket while the engine is running. If engine speed changes noticeably, you have a vacuum leak.

HTH