84 nissan/datsun720

[fromm]

I have an 84 nissan pickup 4x4. it just started to lose power and start jurking around some times. It is not the fuel pump/filter. the carb bowl is full of fuel when this happens. It does have a sensor on the carb that when not plugged in will cause it to die. Could the sensor cause this. Or is it something else. Please help.

[PEZi]

could be a lot of things man... what sensor is it that you are talking about?

have you checked the choke in the carb to see if its working properly?

have you checked for vacuum leaks?

and are you sure that there's nothing wrong with your ignition system causing it to misfire?

there's a lot of things it could be... maybe a little more info about the problem... or maybe any modifications you have would help the situation

[fromm]

I dont know what the sensor is, its the only one on the carb. The problem comes and goes it is not consistant. I dont know if its the ignition or not. if one of the coils is going out could that cause it. The choke is working great.

[PEZi]

i don't believe the sensor would cause this...

if you think the fuel system is all working properly... then it's most likely in the spark

the problem is it could be anything from a bad plug to dizzy cap... maybe a coil... maybe wires

don't count out vac leaks tho... it seems its not those in this case but it still could be

anyone else have this problem before?

[flinterman2000]

Its the idle solenoid that he is talking about. Once disconnected the engine won't idle. I had this problem once with my Galant. It was one of the lasers (I'm not sure if its the correct name) in the distributor. This is want causes the break in current in the dizzy for the voltage to be redirected to the spark plug wires. But he should check for a misfire, bad dizzy cap etc before checking the dizzy itself. If its not constant it might not be the dizzy but a bad wire some where.

[fromm]

Its not consistant at all some days it doesnt do it. But when it does, I mean it lose all power. but never dies just goes to an idle.

[breadbox]

Do you have an oil pressure gauge?

When was they last time it had a tune up?

Mine had low power when it was running on 3cylinders, so it could be spark dropping out on a cylinder. sounds like a spark issue to me.

[fromm]

when i say lose power i mean it wont gain speed it slow way down. plugs and wires arent that old. a few months.

[turbojunker]

when i say lose power i mean it wont gain speed it slow way down. plugs and wires arent that old. a few months.

If its not in the distributor, you could try checking the catalytic converter. One that's plugged up will make it sluggish when it overheats enough.

[dlarsona]

Just before you lose power, does the truck start to misfire? Will it run if you put in the clutch but it sounds bad when doing it, then if you try to drive, it has no power at all?

There shouldn't be any sensor on the carb. That connector is for the choke and if the choke is coming on while driving, you may have a problem there. I bought my '84 for $200 from a guy who thought this was the problem he was having. Turns out there were two other problems:

1) The Fuel Pump Relay was going out. Eventually it quit working entirely. I wrote an article on it HERE: http://hubpages.com/hub/The-Da...l-You

2) The ignition coil power wires from the fuse block should be checked. Check the fuse first but Ignition Coil #2 wire is probably the fault. There is a nasty kink in the wire harness just before it passes through the passenger-side firewall to the engine compartment. The wire may be overheating and you'll lose voltage to Coil #2 when it does - if the fuse doesn't blow first.

Hope that helps.