car's running rough.
 

in the past few weeks, my car's been running like crap. it sputters at WOT at around 4500 rpms and past, sounds like someone's shooting an ak47 under my car/out the exhaust. it would also do it in the city. it wouldn't replicate it in neutral free revving, only under load.

well, to start things off, my fuel pump had been going out, so I replaced it with a 255lph pump and a new filter. i also put on a new coil wire. soon thereafter, my car shot a code 13 and 34. i checked the MAP sensor seal, it was good, wiring was good, voltage good, so I swapped in a new MAP sensor. after this, it drove fine in the city but still made the gunshot noises at WOT. I took it to get the codes cleared so the parameters set by the computer would be like that of stock parameters. after i did this, car ran like shit all together again sputtering in city and WOT driving (leave from stop light, feel car choke, rpms drop and go back up). i drove it another 10 miles or so, and the car never shot another code.

what am i looking at here? after all the things i've done it seems like it's about time the opti would go out... none of my wires are arcing, it's not like it's a misfire, it's like the car's choking. is there any way to test the opti?

thanks.

Try the coil itself. Maby its bad.

could i take the coil to someplace like autozone and get it tested? does the coil interface with sensors like the MAP? if not, I don't see why it would be the coil. All the symptoms seemed to point to the MAP sensor I was getting a code for.. would a bad O2 sensor cause symptoms like this? i can try to take a video if anyone cares..

Test the coil:
http://shbox.com/1/coil_testing.jpg

Get a scanner that can read real time data and see if the o2's are oscillating within the full required range.

The opti can cause hesitation and backfiring that you are mentioning. No real way to test it though.

Yes, autozone has a coil tester that plugs in and does the test.

It could be IMC too, but what your discribing reminds me when my opti went out. I had the same symptoms, when it acted up it would fall on its face like it was bogging out.

They don't plug anything into the coil like they do with the ICM, they just use a ohmmeter to test it.

Autozone out here has something they plugged into it and it has few LED lights that lit up if it was good or bad.

That's weird, cause that's what they have to test the ICM, but not for the coil at any of the stores I've been to. It's like 5 pairs of LEDs, red and green. They all have to go green to pass the ICM.

Oh ok your right then, its been a while since I had anything tested there.

Then I would say Crows93Z to use that link you posted up ss.slp.ls1

Id like to add, when my opti was going out I heard some strange noice come from the front of the engine like what your discribing.

thanks for the help guys. i changed the ICM like 2 years ago, would it go out that fast already? it wasn't symptoms anything like this before it went out..

well it threw a code 13 which i thought was bad O2 sensor wiring... but would one bad O2 sensor cause problems like this?

Well if one o2 is bad, it won't be properly monitoring the A/F ratio of one bank. You could be running rich or lean in half of your cylinders.

where do they sell single wire O2 extensions? maybe i just suck at soldering.

figure it out?

Yea, I was curious as well. On a '93, which is speed density, at temp. the O2 reading are pretty important and could cause the poor driveability being described. It also sounds like yet another opti...I just hate jumping on that opti condemning bandwagon but it always seems to be the case. I think they get wet by previous owners who don't know what they are doing in regards to an opti and that care should be taken when draining coolant or driving in rain as they charge 12" deep puddles at 45 mph...