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280z heat and low.rev bucking


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Okay so i guess i start off with its a 1978 280z non turbo 5speed. New injectors, injector connections,mAf,temp sensor,thermo switch,radiator,fan clutch works,water pump works,what i beleive is an aftermarket 280z fuel pump hard wired to the battery on a switch, oil change and checked for vacuum leaks(none). So the car heats up past operating temp fast even in the cold mornings within 5 minutes and stays there doesnt change with speed or sitting still. After like 15-20 minutes the car will buck but only from a dead stop and under 1500-2k in first if i rev it past that and then release the clutch it doesnt happen.the bucking isnt bad. It idles perfectly at 750 and revs dont bounce or jump. Starts up fine and revs smooth in natural all the way up to 6k the speedo jumps under 20 but stops after that. Any ideas on whats.causing the constaint temps in 50° or 97° temps it just stays at the "m" on temp in the gauge once it warms up (within 5-8 minutes) and the bucking at low revs from a stop? I can move the dizzy rotor but only rotational and not alot but i feel like it ahouldt do that? And ideas would be nice i love my Z and want to drive her stress free

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Any ideas on whats.causing the constaint temps in 50° or 97° temps 

No idea what this means^^

 

The bucking is typical of a lean condition, assuming timng is correct and you're driving correctly.  Either low fuel pressure or an AFM and ECU that run on the lean side.  Usually there is some popping back through the intake manifold though, if it's lean.  A common fix for that problem is to install a potentiometer in the coolant temperature circuit to add a little resistance and trick the ECU in to thinking the engine is colder, to add more fuel.

 

But, you don't have any measurements in your post.  You really need to measure fuel pressure, ignition timing, and resistance on the coolant temperature circuit, at least, to have a starting point to work from.  Without numbers it's all guessing.

 

The movement of the rotor is just the centrifugal advance mechanism moving.

 

Read the Engine Tuneup chapter - http://www.nicoclub.com/FSM/280z/

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