1995 aspire hessitation issues

[Dead_Moose]

Well I'm back after 5 years just reading, I finnaly re upped.....

I'm having issues with an Aspire i bout a while back. Under moderate to heavy acceleration, it has a bad hesitation. spit and spudder ect. ease off the throttle and she'll idle just fine. even sitting in the driveway idle just fine go to WOT spit and sputter. but if I slowly ease the rpms up it will run to the red line, same with driving down the road. I have done plugs wires cap and rotor, sea foam the intake, seafoam in the tank, lucas injector cleaner another tank, no fix yet. any ideas? its a 5 speed, with 200k. what gets me is it idles just fine. The only thing I can think of is the distributor is getting old and not putting out enough spark. its one of the distributionand coil in one deals or with the cat taken off (wasn't me the previous owner did it) and no o2 sensor it s dumping way too much fuel in limp home mode, but no check engine lite(lights up just before start so the bulb is good)

any ideas?

 

[martin]

sounds like it's running lean. Wild guess would be a vacuum leak.

 

[kkjb4x4.0]

rich,,lean,,the lack of 02 sensor if required would be my first guess.

 

[rusty ol ranger]

Are you sure that isnt normal accleration? I mean, that lil 1.3L doesnt make a whole lotta power

lol but seirously, change your fuel filter.

later,
Dustin

 

[fastpakr]

Dustin, he made it pretty clear that it will run to redline in neutral or on the road as long as you ease in slowly, but won't do either one if you tip in hard. That positively eliminates a fuel starvation issue. Pulling the codes is really the appropriate place to start. However, there are some interesting red flags here. It's an OBD-II vehicle that isn't throwing an obvious CEL even with no cat. Something has to have been done to keep the light off, because it is designed to monitor for catalytic converter efficiency. Figure out what's been hacked there, then scan the codes and repair appropriately. Vacuum leak is certainly likely, the cat needs to be reinstalled, one or both O2 sensors may be causing problems, etc... Fix the cat and whatever's keeping a code from being thrown, then scan and repair the rest.

 

[Dead_Moose]

fastpakr,

Its a 95 so it only has the under hood type computer (obd1?) I am thinking that it just needs the o2 sensor put back in or there's something going on with the ignition, not putting out enough voltage, sensor starting to read slow(cam or crank). I'm just not sure what the voltage should be coming out of the sensors. I hate like hell to buy a distributor at $150+ hell thats half of what I paid for the car.....

thanks for the input so far

 

[fastpakr]

good deal. i didnt realizw aspires were a year behehind rbv''s on the obd-2 switch. have you run koeo and koer code tests yet?

 

[rusty ol ranger]

Actually it could still be a fuel issue....i beleive.

Easing the throttle in to WOT and easiing to it redline allows the engine to increse revs little by little, therefore not needing the sudden "burst" of fuel it would need to go from idle to redline all at once. Does that make sense?

Going down the road would be the same thing. Its going to suck alot more fuel on a full throttle start then it would easing the acclerator to the floor.

OBD I should be fine with out cats....but the O2 sensor might be an issue. I dont know much about the elctronic part of it, but me personally i always start with the simple things....and a fuel filter is as simple as it can get, and its a good idea to change anyways.

later,
Dustin

 

[fastpakr]

Actually it could still be a fuel issue....i beleive.

Easing the throttle in to WOT and easiing to it redline allows the engine to increse revs little by little, therefore not needing the sudden "burst" of fuel it would need to go from idle to redline all at once. Does that make sense?

Going down the road would be the same thing. Its going to suck alot more fuel on a full throttle start then it would easing the acclerator to the floor.

No, it makes no sense at all. Whether you ease into the throttle or bury it, the amount of fuel required once you at at high RPM is a constant. There's a brief pulse (mirrors the function of the accelerator pump) but that's nothing compared to the fuel demands of a sustained load.

 

[rusty ol ranger]

Yeah, i understand that once you hit 5500RPM (or whatever the redline is on that thing) the fuel need is constant. But if you ease into the gas the engine is only useing enough gas to rev in small incriments. But obvisouly if you mash it all at once you get a HUGE burst of air, and the computer dumps a ton of fuel to compensate for all the air. But if you open the throttle little by little then it has more time to get the fuel that it needs.

I cant really explain it that well.

The end result is yes, it gets the same amount of fuel, but when you stab the pedal it needs it all at once, if you ease the throttle it doesnt.

later,
Dustin