i have a 87 nissan 4x4 truck and 4 cylinder z motor. truck had a lot of miles on it nad was missing really bad

Question

i put new plugs in and installed new timing chain and tensioners. truck stills misses and idles rough. has popping noise in caburator. dont know what to do to sove problem. i also tried to set timing and still running rough. do i need a new head or what?

Answer 1

Torque all the studs on the head. The heads might have loosened over time and if the heads aren't torqued to precise tolerances it may run rough and have less power.

Answer 2

I am so sorry Vacuum leaks really make that engine run rough spray flammable carb cleaner around the intake manifold to the head see where the engine smooths out. Please be very careful 8 spark plugs and wires might torch the carb cleaner spray just a little at a time to keep the fire small. Might just need a intake gasket. Twin coils intake side runs all the time exhaust turns off at 4000 rpm's Many times the distributor rotor sparks across you can try just a rotor bolted on the distributor shaft. If the popping is constant your intake valve might not be closing or was bent. Those NapZ engines have manual valve adjusters find the really loose valve and look at the spring height shorter than the rest you found a bent valve. Let's all celebrate! You fixing the misfire and selling this 20 year old horse to buy a NEW Nissan Fronter V-6 268 horsepower 4.0 liter engine that gets just as good gasmilage as the 2.4 liter. Or just disconnect the truck from life support keep it from draining your wallet put a for sale sign on it.

Answer 3

I'm not sure on the newer trucks but this is something to think about. I had a '91 S10 4 cylinder that had very little power. A friend had a similar year with a 6 cylinder that had great performance. I got 1mpg better than he did. Sometimes the engines are underpowered so have to do more work to move the truck...and loose gas mileage. If you go 50-55mph everywhere it may not matter. But the small engines may not like higher speeds.

Answer 4

Heads don't cause missing and idle problems. You can't set timing unless you have a timing light and know how to use it. The popping in your carburetor sounds like advanced timing. If the popping noise started after you installed timing chain then you missed the timing marks on chain .

Answer 5

this problem sounds like a coil or spark from your distributor to your engine block,change all wires,removed coil wires in the dark and have someone turn over engine,look for sparks..

Answer 6

Buy you a SR20DET & drop it in that badd boy !!