# 86 hardbody died, wont stay running



## Hoodis (Mar 15, 2012)

I was driving down highway, truck started sputtering and died. Truck normally runs like a champ. Seemed like it was starved for fuel. Unhooked fuel filter and it had some crap in it but was flowing good. Good fuel pressure to tbi. When i start it, i have to pump the throttle a lot and it will start and then starts to die. If i keep pumping the throttle it will sputter and surge and bogg down, small pop backfires from tbi. It will not stay running, i can keep it sputtering until my leg wears out and can pump no more. Gas is from same place i buy all my gas and never any problems before.

86 4x4 2.4 z24 injected, 117k miles, complete tune up at 106k miles. I hardly ever drive it, 9k miles in 3 years.

Any ideas?


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## TheRepairMan (Jun 30, 2009)

Hoodis said:


> I was driving down highway, truck started sputtering and died. Truck normally runs like a champ. Seemed like it was starved for fuel. Unhooked fuel filter and it had some crap in it but was flowing good. Good fuel pressure to tbi. When i start it, i have to pump the throttle a lot and it will start and then starts to die. If i keep pumping the throttle it will sputter and surge and bogg down, small pop backfires from tbi. It will not stay running, i can keep it sputtering until my leg wears out and can pump no more. Gas is from same place i buy all my gas and never any problems before.
> 
> 86 4x4 2.4 z24 injected, 117k miles, complete tune up at 106k miles. I hardly ever drive it, 9k miles in 3 years.
> 
> Any ideas?


Your last statement may be a clue as to why it's giving you problems now, and the age of the vehicle doesn't help. Vehicles hate to sit. Sitting can cause a huge variety of problems. Batteries go bad quicker than usual causing charging systems to work harder. If the alternator can't keep up anymore the engine won't run right. Corrosion can be a tough problem in any part of the electrical system, and hides really well under battery terminals and ground connectors. Distributor caps, spark plug wire terminals, and ignition coil terminals can also hold condensation and corrode. Spark plugs can easily become fouled causing the symptoms you've described, especially in combination with all these other possibilities.

I'd start with some fuel system cleaner like Seafoam or Berryman B12 and let it be working while checking all the other stuff. You gotta start somewhere!

-R


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## SPEEDO (Jun 9, 2003)

might also check for any codes...


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## Hoodis (Mar 15, 2012)

I'm pretty sure it's not electrical, I can put gas directly into tb and it will start and run smooth until fuel is burned off. But i cleaned up everything anyway, so I am gonna replace fuel filter again and put some sea foam in and unhook fuel line and cycle it through and see what happens. I plan to clean maf sensor too and hope it solves it. Injectors are expensive. 

If it helps diagnose, I was 90 miles into a 100 mile trip when it went from running strong to quiting.

Thanks


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## Hoodis (Mar 15, 2012)

I'm pretty sure it's not electrical, I can put gas directly into tb and it will start and run smooth until fuel is burned off. But i cleaned up everything anyway, so I am gonna replace fuel filter again and put some sea foam in and unhook fuel line and cycle it through and see what happens. I plan to clean maf sensor too and hope it solves it. Injectors are expensive. 

If it helps diagnose, I was 90 miles into a 100 mile trip when it went from running strong to quiting.

Thanks


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## Hoodis (Mar 15, 2012)

HELP! I am about to go crazy with this thing. 
I have taken tbi off, cleaned it, gasket good, cleaned maf sensor, cleaned air warming plate. Checked all vacuum lines. 

I can pour gas into tb and then put my hand over tbi and restrict air and keep it running, and rev it up and adjust my fingers to control air intake volume and it runs fine. Take my hand off and it dies.

Pumping the pedal from inside it will sputter and backfire out tb. But it runs great for as long as i want when i manipulate the airflow with my hand.

Would a weak fuel pump cause this and if so what should the pressure be?
I said earlier it had good pressure i should have said volume, when i turn the key on it pumps good from fuel line when disconnected from tbi, it pumps for about 8 seconds then pumps shuts off, cycle the key and it starts pumping again for 8 seconds.

Thanks


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## digdug002000 (Oct 16, 2011)

Your injectors are probably clogged or shot. Same thing happens to my pathfinder. Need to replace the injectors in the tbi.


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## SPEEDO (Jun 9, 2003)

before you spend the $$ on injectors, CHECK FOR CODES... could be the injectors, but both of them? did you check the connectors? (when I lost a injector in mine, the truck went into "fail safe")


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## Hoodis (Mar 15, 2012)

No codes, injectors are clean.


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## saudade (Apr 10, 2010)

Hoodis said:


> injectors are clean.


How do you know this? Are they both firing?


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## SPEEDO (Jun 9, 2003)

are you getting fuel to the injectors?


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## Atomus (Mar 15, 2016)

*Apr 9th, 2012, 09:31 AM*

can you here the fuel pump when you turn the ignition on?


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## Glamisman (Feb 12, 2016)

There are 2 fuel lines that come off of the fuel tank, one for high pressure 40-ish psi and return... after 30 years they go bad and get soft and collapse... no fuel out no fuel back. The second issue is the fuel pump itself. It sits in a well inside the tank and the filter screen will deteriorate and jam the pump completely or restrict the flow enough to cause your issues. If it was me, and it has been me, I would drop the tank and take a look. Then I would take the filter off in the engine compartment and try to blow through it. Then I would blow through both lines while you have it apart... kind of a messy job but that is the only way to know for sure where the problem isn't.


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## NissanTruckGuy (Mar 27, 2017)

*1990 Same issues*

I have a 1990 Hardbody with 4 Cyclinder. Starts up fine, drive 4 or 5 miles no problem, running like a champ. Cut off the engine, restart after a few minutes no problems again, drive for about 1 mile more and it starts to sputter and bog down, tries to cut off. If I pump the gas I can keep her going for the next half a mile and it corrects itself after that and I am good for 5 more miles again. What is that going on?

Thanks


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