My '79 is normal, to know what normal feels like.
'81 has had a very sensitive throttle response for years of posts. I built, swapped in the engine. Runs great, except pushing on, letting off the gas is RIGHT NOW. Fine for flooring it, not so fine otherwise.
Suffice to say I have done everything once. Bushings, linkage, switches set properly, tested, low disconnected. Timing, ...air fuel meter,...
My question: In my quest, which (single) items to swap first, second, third, etc. most likely to be causing the problem ? I.e., air/fuel meter, then throttle body, then brain box,...
*%#! man must triumph over machine. As Cheech said, " You better work dis time or I gonna make a go kart outta you !"
Sensitive throttle (14)
I bet the answer comes down to the 79 distributor has a both vacuum advance and retard, and the 81 is advance only. Technically the two also have different ECUs, but I doubt that is the problem. It could also be something like a broken advance spring in the 81 causing advance to come in very quickly.
Same flywheels? Light flywheels make a difference, but standard E12 is fairly light.
Same flywheels? Light flywheels make a difference, but standard E12 is fairly light.
Mike W.
02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
Thanks Mike. I tried Google Search for testing the distributor advance spring. Recall something about messing with the rotor ?
I'm happy to swap in either of two spares. Having them has made using one as a test to see if I can take it completely apart a someday goal...
Although it may be an exercise in wasting time if there's a test to see if it's fine without taking it apart.
I'm happy to swap in either of two spares. Having them has made using one as a test to see if I can take it completely apart a someday goal...
Although it may be an exercise in wasting time if there's a test to see if it's fine without taking it apart.
Without suggesting it's a definitive test, just try rotating the rotors by hand. If there is a noticeable difference, something is suspect. Now that's not saying all is well if you can't feel a difference, just that it points to a problem if you can.
Mike W.
02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
The solution is to become am L-jet expert, read, study, experiment. Oh well.
My thinking is old carburetor. Injection seems to be about air, where a kart engine that stumbles wants the fuel mixture adjusted. I think: gas pedal, linkage to throttle body. But the throttle body isn't about fuel, it's air. There's an air fuel meter box between it and the air cleaner, and that has a big plug in the side of it with a hundred wires going to the electronic control unit (ECU, acronym that makes no sense until studied, translated, memorized.)
What is making pushing the gas pedal not smooth, but sensitive jerky ? Compared to a '79 528i, maybe not another '81, which I can't know unless I drive one.
Is this critical, life changing ? Hardly. Just drive it. Maybe as all (remaining) '81 owners do, never knowing any different.
I rebuilt another distributor. The rotor feels very firmly attached to an inner spring. Twist it, it snaps back. The vacuum advance routine.
I doubt the one in the car is any different. It occurred to me to just add the vacuum retard line. Remove the plug/cap under the throttle body, run the tubing.
I guess it feels better. Too used to it being different from the '79 to say, " Finally ! fixed !
Question: If the distributor is the same, with the retard nipple just hanging out there naked on an '81, what's the big improvement upgrade in plugging the throttle body nipple in '81, to omit the vacuum retard feature ?
Is there one less wire in the ECU ?, was it to save money on all the vacuum tubing ?
My thinking is old carburetor. Injection seems to be about air, where a kart engine that stumbles wants the fuel mixture adjusted. I think: gas pedal, linkage to throttle body. But the throttle body isn't about fuel, it's air. There's an air fuel meter box between it and the air cleaner, and that has a big plug in the side of it with a hundred wires going to the electronic control unit (ECU, acronym that makes no sense until studied, translated, memorized.)
What is making pushing the gas pedal not smooth, but sensitive jerky ? Compared to a '79 528i, maybe not another '81, which I can't know unless I drive one.
Is this critical, life changing ? Hardly. Just drive it. Maybe as all (remaining) '81 owners do, never knowing any different.
I rebuilt another distributor. The rotor feels very firmly attached to an inner spring. Twist it, it snaps back. The vacuum advance routine.
I doubt the one in the car is any different. It occurred to me to just add the vacuum retard line. Remove the plug/cap under the throttle body, run the tubing.
I guess it feels better. Too used to it being different from the '79 to say, " Finally ! fixed !
Question: If the distributor is the same, with the retard nipple just hanging out there naked on an '81, what's the big improvement upgrade in plugging the throttle body nipple in '81, to omit the vacuum retard feature ?
Is there one less wire in the ECU ?, was it to save money on all the vacuum tubing ?