Beer30

i have a 95 Lumina with 3.1 and having issues with acceleration under load, when i need to give gas to pass or am going up inclines, car runs great till i have to give it gas, shifts fine otherwise. could i have a fuel injector, filter, or pump problem, bought car from nefew and and he mentioned it may be speed censor any help would be great as its my work car and drive 33 mles 1 way to work need the mileage. ive change plugs, wires, and wheel bearing but still needs some help thanks jeff 1 last thing my ABS light is on and not sure if this could be giving me issues

SilentObserver64

Could you give a little more insight to your problem? You say it's having problems when you press on the accelerator, but what exactly is it doing when you have to press on the gas and go into the passing gear? It it spitting and sputtering? Is it not wanting to shift into passing gear? Is the motor bogging down? Does it accelerate slowly? Describe exactly what is does before, during, and after you mash the gas to go up a hill, and/or passing someone. Thanks.

Beer30

i have a post below about clicking noise, but car runs fine until its under a load acts sluggish in passing and going up hills, it was acting wierd and make a clicking noise in front left at 30-40 mph but now its sluggish passing and going up hills thanks for any help

themidiman

I had this issue with my Lumina when I was in high school. Almost the exact same issue. Had it diagnosed and they said it needed a fuel injector. Didn't fix it, wasn't worth it. Sounds like the same thing

tech2

viewing live datastream would help narrow down the problem; without that data I would start testing ignition and fuel systems.

spark demand is higher on accelleration which could lead to a misfire if the ignition coil is weak. You can do a quick check by recreating the condition: vehicle not moving, idling in drive. hold the brake firmly with your left foot while you step on the gas with your right; briefly (3 seconds) to 1500 rpm. This will create a load that will increase spark demand. If misfiring occurs suspect a bad coil. Other things that increase spark demand are worn spark plugs, distrib cap/rotor, plug wires.

2ndly check spark output with a spark tester.


if the fuel pump can't supply the correct pressure it may lean the system out under accell. check fuel pressure and compare to spec. a quick volume test is to remove the regulator vacuum hose (pressure should increase) then bring the engine to 2500 rpm...if the pressure drops more than 2psi the pump can't supply the demand underload.