FJ62/3FE starts but engine chokes and dies if I apply throttle

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TheElegantFox

TheElegantFox

Joined
Feb 16, 2019
Threads
63
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735
Location
Raleigh, NC
Just got my truck back from the shop where I had some wiring done. I let it sit for a day or two and now I can’t back it out of my driveway. It’ll start, roughly and the idle is loopy. As soon as I apply the accelerator, the engine sputters and chokes out, but I can hit above 1k RPM if I use the throttle knob.

Any ideas on what to check?
 
Did it drive home ok from where you had the work done? What wiring work was done?

Check your battery connectors are clean and tight and the wires are in good shape
- My other thoughts would be look for a loose, broken, or corroded ground wire
- unplug and plug back in the AMM/MAF (whatever the 62 has).

Will the truck start normally and idle indefinitely? When was the last time the fuel filter was changed?
 
Seth S said:
Did it drive home ok from where you had the work done? What wiring work was done?

Check your battery connectors are clean and tight and the wires are in good shape
- My other thoughts would be look for a loose, broken, or corroded ground wire
- unplug and plug back in the AMM/MAF (whatever the 62 has).

Will the truck start normally and idle indefinitely? When was the last time the fuel filter was changed?
Click to expand...
I had the battery cables replaced and they’re in great shape, I’ll check over the whole line to make sure it’s good. The truck drove fine for about 4-5 days afterwards. Starting is rough and it doesn’t turn over every time. Once it is started, the idle is pretty rough.

Not sure about the fuel filter, that might be worth looking into.
 
How old/new is your battery? An old battery...or an alternator not charging properly could create all of these issues. Low voltages can send sensors out of range and confuse the efi computer. Poor cranking etc.
 
You might want to do the Factory Service Manual checks/adjustments on the Air Flow Meter and the Throttle Position Sensor. But also check the stuff Seth suggested especially grounds. Any wiring other than battery cables?
 
The battery is brand new and the only wiring replaced was the battery cables.

I’ll find an online manual and check those spots.
 
Well, I ended up getting it moving by revving the engine a bit. After than I drove it to Autozone with some occasional stalls coming from a stoplight start.

Hit the MAS with some cleaner and put some GumOut fuel cleaner in it and it starts and runs a bit better.

Still getting occasional CELs, not sure what that’s about.
 
Thing is it's not a mass air flow sensor. There's a little flapper door in there that opens/closes some micro switches and also provides variable resistance to the ECM to tell is how much air is being drawn in.

Not saying the cleaner is going to do harm but it's not the same as cleaning a MAF. Although if the flapper door is sticky it could definitely be causing issues.
 
I had a feeling cleaning it didn’t make much difference. It was already pretty clean, so that makes sense.

Any other areas I should check? I’m suspicious of the fuel system since revving it out seemed to clear it up momentarily.
 
Did you check your TPS? Could need adjustment or replacement. Does your distributor turn without you loosening the bolt for it? Maybe the fuel pressure regulator? I'm just throwing stuff out at this point.
 
Make sure your distributor isn't loose, retarded timing could do what you're describing. Probably 100 other things too though
 
A bad coolant temperature sensor can cause a lot of headaches too. Testing is just a matter of reading the resistance across it from cold to normal operating temperature. Inspect any and all fusible links and look for broken and corroded ground wires.
 
Well, the engine died when I was crawling away from a stop at an intersection, so it’s flatbed time now. Felt like I lost all fuel going to the engine.

Starter and battery were fine, but it won’t crank over.
 
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