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1999 Chevrolet S-10 difficulty starting

When it gets cold my truck doesn’t seem to get fuel to the carb. If I dump gas in the carb it fires but won’t keep running for a few times. Today I hooked up my battery charger to give it a boost and it started right away. An hour later same problem until I hooked up the charge… then it fire up again. What’s going on?

Well, for starters, this truck was not built with a carb. Have you removed the fuel injection and added one?

No…with that being said it shows my ignorance of mechanical abilities:) I’m just confused why hooking up a battery charger would cause it to start when a strong turning over with the battery wouldn’t. Would the charger give an extra boost to the electric fuel pump to push enough fuel to the injectors? If so, is there possibly a electrical malfunction and not a gas not getting thru? Thanks for your input.

Are you now saying you did not really pour gas in but only used the battery charger . If so I think a new battery might be the answer .

If you’re saying a battery jump alone takes the problem away, then have your old battery and charging system checked. Clean both ends of both battery cables, replace battery if bad, and or alternator if bad. The engine needs proper voltage to start and run right.

First I pour a little gas in…it fires but won’t keep running. Then I hook the charger and it fires right up w\o pouring gas and keeps running. During warm weather (above zero) it has no problem starting and keep running.

P.S… Battery is pretty new. I’ll clean the post etc. Also I have another S-10 that does the exact same thing. Both batteries are maybe a year old. (I know… buy a Ford:)

Okay…I cleaned the battery posts…the battery was bought 2-17-17. We’ll see what happens in the morning. It’s suppose to get below zero:(

Update: I cleaned the battery cable ends and battery. Went out this morning… same song. Wouldn’t fire up so I hooked the charger for a jump and she started right up. Battery only two years old. It seems like the fuel pump isn’t getting the power to push gas.

Check the fuel pressure.

The fuel injection system used in your vehicle if it has the 4.3 L V6 is called Central Port Fuel Injection.

And the CPFI system has what is called a spider assembly.

https://www.rockauto.com/en/moreinfo.php?pk=1053753&cc=1353642&jsn=482

The spider assembly has mechanical poppet valves at each cylinder. These poppet valves rely on the fuel pressure to blow them open to inject fuel into the engine.

If the fuel pressure is too low, the poppet valves can’t open.

The fuel pressure should be 63 PSI.

Tester

Thanks… I have a dumb question. How come the extra electrical boost solves the problem?

Have you checked the positive battery cable for this?

A voltage drop to the fuel pump will cause the fuel pump to run slower.

Tester

Yes, and cleaned it and battery with baking soda and a brus

Did you peel the red cover off to expose the terminals?

Tester

Are there any check engine lights and associated codes when the thing is warm and running? If so, start posting those here. I have the same truck except in a 2000.

If there is a check engine light, drive the truck to a parts store. Most big chain stores will read your codes and give you a printout. You may have one of more code. They will be something like P0420. Post the numbers here!

Didn’t know that was possible. I’ll do that tomorrow. Thanks.

The McParts store customers who rush to get the free battery installation often return a week or so later because they didn’t clean the cable ends. Just removing the cables and installing them on a new batter will usually result in a short working connection. In the long run it would be worthwhile to pay someone to properly test the charging/starting system and repair and replace what was needed. I have seen cars with new alternators new batteries and new starters that still required jumping off… But think of the money they saved!

There are quite a few causes for a “cranks ok, but doesn’t reliably start and run” symptom. Given that charging the battery seems to fix it for a while, makes sense to focus on the battery and/or the alternator as the cause first. The computer, ignition module, and fuel pump are all voltage sensitive and must be supplied with the correct voltage at all times or drivability problems will ensue. The easiest test is to verify the battery measures about 12.6 volts before the first start of the day, then 13.5-15.5 immediately after starting the engine, at idle. Ask your shop to make that measurement; or if you have an inexpensive DVM you might could do it yourself and report back here what you measure.

I had as strange issue with my 2000 S-10 once. My dad liked my truck so well that he went back to the dealer and bought basically the same truck the next day. So we both had a 2000 S10, 2WD, 5 speed, with the 4.3L engine.

One day I made some comment to my dad about a strange electrical problem I was having with the truck. It would die just going down the road. Everything would shut off and all light and indicators would go dark as if I had turned the key all the way off. The engine would then restart rolling in gear a moment later and everything would seem normal. My dad was like “That is exactly what mine did when the battery needed to be replaced.” I was somewhat skeptical but took it and had the battery tested. I don’t remember the parameter that failed but the battery tested bad. I replaced the battery and this never happened again. The strange part about this was that the engine cranked over strong and it always started right up with the “bad” battery. Something was apparently not in range so maybe that is the situation here.

I agree. Have it checked out and don’t just throw money at it.

Checked battery this morning. 12.3 volts Didn’t start.