Hesitation. Unknown source. Any incite welcome.

First let me thank you for your time.
The car is a 1992 Pontiac Grand AM SE V6 3.3L SE. WHen I step on the gas, the car hesitates, I step on the gas a bit harder and she cleans up and goes. But you can feel the hesitation when trying to stay at a solid speed on highways.
Here is what I have replaced so far:
Plugs
Fuel filter
Fuel Pump Relay
Fuel Pump
O2 Sensor
Air FIlter

I am going to check the MAF sensor shortly, but I wanted to see if anyone had some incite before I go any further. It feels like I don't have enough fuel presure, so I am leaning towards the injectors, but they are on the expensive side so I would rather explore other avenue's.

Also I have a code checker, and I am getting 2 codes, 26 & 27. 26 has something to do with a Quad thingy (forgive me, I don't have the book infront of me), and 27 has something to do with 2nd gear. I dont have any other problems though.

Thanks for your time. :confused:

I would suspect the MAF sensor!! Take it out get some choke cleaner spray the fine wires on the MAF sensor till they are clean and reinstall the sensor and try that it should fix your hesitation.

As for your codes the one is a Quad driver fault. A quad driver is an internal circuit breaker inside the computer which controls 4 circuits. If you have no current code or problems than leave it alone.

Thank you for your incite, I will post my results.

Hmm, it is still doing it. Not as bad, but its still there. MAF was a bit dirty, nothing to cry about and it cleaned up like new. I was just talking to a friend of mine, and we started bouncing idea's off one another.

I am stumped right now, the only other thing I could think of is the crankshaft sensor is going bad. I know it controls the timing for the distributor module (starting with 3 & 6 is what its stating). But I dont know what will happen if the sensor is going bad. Meaning if the sensor is going bad will the car still run and give me my problem, or if the sensor is bad will the car not start at all (since the ecm isnt getting the rpm signal from it and wont have the timing info needed).

I think the next thing I am going to do is pull the plugs and check to see if anything is fouling. Might be something as stupid as a broken core in a spark plug wire. :frown: :confused:

if the crank sensor is bad, then the car won't start. the computer need the signal to fire the plugs. sometime it will go bad when driving and cause the car to die out, but won't cause the car to hesitate. are u sure the ignition system are good? have u check the spark plug wires and the coils? the spark plug wires could be arcing and the coil(s) could be bad when the engine is under load.

Thats a small relief. I was just reading up on what it would take to do the job. Was not looking forward to that insanity, plus I dont have an engine hoist...... yet.....

I will check and or replace the wire tomorrow just for kicks and giggles.

BTW, I am also getting a very small amount of backfire. Now according to these resources I am reading ( www.alldatadiy.com and haynes manual) it could be a couple of things, plug wires being one of them.

Others include:
Emission system (need to check digital egr)

Ignition timing (dont think so)

Faulty secondary ignition (cracked spark plug wire)

fuel injection system malfunctioning (funny tool they tell you to use. A stethascope (sp?) to liston to the pic inside the injector, tried it since I had one around, they seem to be working)

Vacuam leak at injectors (possible)

Valves sticking (unknown)

I am calling it a night for now, but I will check back here in the morning.

Again, thanks to everyone for trying to help. :)

If I'm reading the discription of your problem correctly, you feel the hesitation at highway speeds also?
If so, it sounds like a secondary ignition breakdown.....check the coils and the plugs you replaced( the rear bank is hard to get to and cracking one of the rear plugs is not uncommon) and I would definatly replace the plug wires.

GMMERLIN has a good point. Look at the wires on the inside as you pull the out. I bet you, you will find one that is black with carbon. If you see that, replace the wire set. Good luck.

UPDATE
Changed Plugs wires
Changed PCV valve (might as well)
Changed Alternator (dont ask, I have the big audio system and it likes to eat regulators)

Hesitation still present. Car bogs upon take off. Hitting the gas hard fixes problem. She still flutters at highway speed. Very lightly.

Backfire still present also. When I say backfire I dont mean a big old KABOOM, I mean it sounds like a little bit of gas is getting into the exhuast and is being burned of. It ONLY does this when in park and car is revved. Its only 2-3 light pufs. I mean very light.

SIDE NOTE:
I had some work done to the car recently. Oil change, both lower ball joints and front struts and rear shocks. WHile changing the plug wires today I noticed a wire disconnected. I can not figure out where it goes. It looks big and important.

Upon checking the location of this wire with onlin manuals it might be something very important. Its coming off the same harness as the O2 sensor is. Its a jack, like the male end of a jack.

The online manuals tell me that in that area it could plug into a couple of things. The fuel pump switch/ oil pressure sender. The knock switch or the speed sensor. Speed sensor is fine.

I don't/ can't see anywhere that this wire may possible go. I have felt around the whole back of the motor like a school boy on prom night, but not getting anywhere.

Again its coming off the same harness as the O2 sensor. Could this be my problem? Where is this wire supposed to be? Its not that long, I have tried looking for a place withing the length of the fire but with no success.

Any other ideas? Thanks again for your time and effort.

have u check the coil?

the spec. for the coil is 500-1500 ohms and the injector is 11.8-12.6ohms.

thanks, I will hit them with a meter in the morning.

no problem. let me know what happen.

OK, stupid question. I yanked one of the coil packs today and it dawned on me. Which points am I supposed to test from? The two spark towers? The slots that mate with the prongs on the distributor module? Or the module itself??
I tooks some readings anyway, not sure if they were taken the right way. they seemed to match each other.

On the coil pack from slot to slot (bottom side of pack that mates with module) dead short. All three

From spark tower to spark tower (if I remember correctly) was about 6k.

Where should I be testing these coils at?

Thanks again, sorry if I am being a pain......

Test from the coil towers.

Problem Solved :
Porous vacuum line at fuel regulator. :loser: Thats one for the books. Thanks again for all the help everyone.