jump started my golf cart and now my ranger runs bad

[joehrs]

I was working on my golf cart and was jump starting it with my 98 ford ranger 3.0 without the truck running and immediately after I went to start my truck and it wouldnt idle and runs rough. Idle rpms dropped from 950 normal to 500. I did notice if I unplug my alternator it idle a little better and faster. I also noticed when revving up my ac clicks on and off.
If I hold rpms at 2500 it drops to 2000 and then back up to 2500.
Any ideas?

 

[CrowRanger]

Pull codes? or have a check engine light on?

one time i jumped a customers car with my truck and my Map sensor died after i turned my truck off and back on again. coincidence maybe?

 

[RonD]

Just for future reference on cars/trucks with computers you need to disconnect at least 1 battery cable when jumping to another battery/vehicle, both is better.

And NEVER jump while your engine is running.
Also if you need to charge your battery disconnect cables first.

I would get a voltmeter and test your voltage at the battery with key off
Then at the battery with engine running.

key off battery voltage needs to be 12.3v to 12.7volts
Just after starting battery voltage should be 14.2v to 14.9volts
After engine has run for a few minutes voltage should be down to 13.6volts, turn on headlights and fan blower to high, the voltage should drop and come back up to 13.6volts

If your voltages are low check the fuses in the engine fuse box.

And NEVER disconnect alternator(or battery) while engine is running.

These are all old school tests, I know because I am old school, lol.
But you will F*up your electronics if you start causing power surges, i.e. disconnecting and reconnecting battery or alternator while key is on or engine is running, or Jumping another battery.

The new electronics are way way............way better than the old electrics, been there KNOW that,
But the cost of better running longer lasting systems is that you need to know what you should and shouldn't do.

 

[joehrs]

test drive

Took it for test drive. Odd thing.........my temp has always ran at just below 1/2 on the guage.
Now it stays at 1/8 ....never higher and does not seem to fluctuate.
Is it possible the temp sensor went bad.....would this have any effect on idle and engine performance? How do I test this ? And where is it located?

Would jump starting possible cause it to go bad?
Thanks
And I have learned lesson and will follow tips on jump starting.
I bought this truck brand new in 98' and it has never given me problems.

 

[RonD]

Check your voltages

Temp "sender" is for the dash gauge, and no probably not bad, check voltages .

 

[joehrs]

Well......took it for a long test drive
Back to normal.
Must of took 20 miles or so for the computer to figurand sort everything out.
Temps now back to normal and no codes.
Running great.
Not bad for a truck going on 18 years old.
Thanks to the responses.