I have been having a problem with my 94 Formula.
It starts up fine, will drive fine for a few minutes and then it starts to surge and backfire.
I was crusing in 2nd gear going about 20 the other day, and very randomly the car jerked back and then back fired. I threw the car into neutral to let it roll a little, then put in back in 2nd tried to gain a little speed and it surged again. I ended up floating back to my house in neutral.
When I got back it smelled very much like gas.

A few days before the car died on the freeway and wouldn't start for about 10 minutes. Once it started it drove about a minute then it backfired and stalled out again. It would not start after that. I came back the next day and it started up drove it about 5 miles then started to surge and stall out again.

If I try to start it right away after it dies, it turns on but sounds like its running very rough. If I wait a little while and then turn it on it seems like its running fine.

Now the smell of gas leads me to believe it's flooding out... Any idea what would cause this?

I replaced the opti about a month ago with an AC delco. The car was running great for about a month, then all the sudden it starts surging/stalling.

I swaped the ignition module and coil to see if it would fix it but no change.
I looked over the opti and plug wires both seem fine.
I also checked my TPS, IAC, and MAP sensor all are reading good.

The car had new MAF, and o2 sensors put in about 6 months ago.

It also is very weird that the car seems like its running great, it has the same power it always had, but will randomly surge/backfire/stall. It always smells like gas when it does.

Any input would be greatly appreciated.

 

I went and ran the car for a little, sounds fine. I tried moving the MAF wires, coil & ignition wires, and opti wire while it was running to see if there was any change in engine idle. No change.

When I replaced the opti I took the smog pump off. When I went to put the smog pump back on I heard a rattling noise inside it, so I pulled it apart and found a washer inside it. When I put it back together it didn't seem very tight anymore. The are no fasteners it just presses together.
I am wondering if the smog pump has a vacuum leak will it cause drivability problems like I am having?

 

the problem your having, sounds like a bad o2 but since you replaced them just 6months ago, i cant see it going bad that fast. Clogged cat possibly?

 

I am having the same problem with mine right now. I put a new MAF on it two days ago, went from screened to unscreened, the other one wasnt working anymore, so i changed it, took it down the road, and all seemed to be fine, then the next day i drove it and sputtered when i got into the gas but ran fine otherwise and so i reseached some places, they had said to "clock" it, so i tried that, then it went to hell, wouldnt idle what so ever at first but would be fine and high RPMs, went outside today cranked it held it at 3k RPMs and it started idleing, went to the store and came back all seemed fine, but when i left again it would idle but would sputter and backfired while driving, i coasted back home, and i still cant seem to figure out what this could be? i was thinking a clogged injector? or could it possibly have something to do with the MAF? i need some help on this as well..

 

So I pulled the #1 plug today and here is what it looks like


Looks fouled to me. They are only about 8 months old, Bosch platinum plugs.
Should I try putting in new plugs? Or should I wait until I find what caused the plug to foul?

As far as the cat being bad, its about 4 months old so I really doubt it.

I also have a descreened MAF, but it's been that way for 2 years and has always worked fine.

What do you mean when you said "they had said to "clock" it"?

 

Just based on what i think, id say wait till you find the source of the problem. No use in wasting a new set of plugs..

I dont think mine was caused by the MAF either, but who knows, have you checked to see if there is an vacuum leaks? im going to check that after i take a break from this hot texas weather

And by clocking I mean, to reposition the MAF so it reads at an angle to the elbow on your air intake system. how old is the MAF on your car? have you checked it? and on the "clocking" i wouldnt suggest it considering mine was running fine untill i did that.. besides after i had done it, i went back to the forum i had found on my phone.. turned out mustang guys.. so idk if it would be a great idea to try lol

 

So this is what you mean by "clocking"


My car has been like this since I got my Ram Air box, because the MAF wires weren't long enough to let the MAF sit straight.
This was done at least 8 months ago, I never noticed a problem after installing.

I just tested Vacuum, 17 HG at idle so that's fine.

I am starting to wonder if maybe the fuel pressure regulator went bad.
I wish I had a fuel pressure gauge to test it.

 

Ok, I finally figured it out. The black/gray coil connector was weak and losing spark after a few minutes. I replaced the connector and it has been running fine.

 

i had a problem with surging 94 t/a auto ! my IAC needed to be "reset"
once i reset the IAC, no more surging at idle ! (got egr problms to fix next)

 

Glad you figured it out.