I have a v6 2.8 fiero. Out of no where car went from running fine to very rough. I drove the car to the store and it was fine. Few hours latter started the car for work and was running rough. In park car don't run as bad. When idle its a little worse and accelerating the car sounds like a nightmare. I checked the distributor and spark plugs and there all good. Car also smells a little rich and i believe whatever the problem is may be linked to my recent loss in engine power. Where should i go from here?

It might be the ignition module failing. Do you know how to take it out? You could take the module to O'Reilly's or Autozone or others who will test it for free. To take it out you remove the distributor cap and then the two small screws that hold the module in. Be careful not to loose the screws. You unplug the two connectors and take the module to the store. If you don't have another car or way to get to the store you could buy a module (have it tested) and put it in at home. If it's not the problem it's good to have a spare module if they won't take it back. I got a magnetic pickup tool at Sears for about five bucks when this happened earlier this year. It was very helpful in removing and installing the screws. I think it's a 6mm nut setter that fits those screws best. You should also replace the heat sink paste on the bottom of the module. It comes with a new module or you can get it at Radioshack.

The connector wires may have become brittle in the heat. You can get new ones from the Fierostore.com or put them together yourself using pigtails from your auto parts store. It's not unusual for problems like yours to be related to bad wires in the coil/distributor area.

[This message has been edited by 85 SE VIN 9 (edited 08-30-2014).]

I would check your fuel pressure. If the exhaust sounds wheezy then look at your cat converter.

Ignition module tested good. About to run a fuel pressure test next and share my results

I post file often for problems like yours:


Your’s could be a common problem and don’t cost anything to check.
Try this:
Watch the tach when cranking if it don’t move you're not getting pulses from the distributor. If so, it could be a faulty module in it or more likely simply corroded connectors at the base of the distributor. Reseating those connectors a few times could clean the pins some and also do the same to the connectors on the coil etc. These cars are old, and old connectors corrode. Such can also manifest itself as intermittent misfires, and engine cutouts.

BTW: lots of folks keep replacing modules and coils thinking they are bad because the new ones FIX the problem, when in actuality the fact that they simply unpluged the connectors and repluged them into the new unit cleaned the contacts enough to make it work again, at least for a while. It's smart, to replace those old connectors with new ones.
BTW: Cliphouse has those connectors

What I have found with misfires.
1. Bad wire connections- high tension and 12V Water/moisture corrosion on the connectors.
2. Defective coil or coilpack. Not common but it happens to 25+ yr old coils
3. Case learn not properly set (OBDII cars)
4. Low fuel pressure
5. dirty fuel injectors
6 Contaminated or stale gasoline - Do you drive your Fiero much? Common in cars that are seldom driven. Some dry gas and running the tank out and refilling works wonders. Since I missed most of the regional shows this year. My Fiero experienced this problem for the first time. Even though I used Stabil preservative, some water droplets apparently got in there.
There are many more causes but the above sem to be the most common.
7 A battery nearing its end life

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

I narrowed down the misfire to cylinder 5. Completely dead. Has spark. Means bad/dirty fule injector correct?

Spark with no 'bang' would usually mean no fuel, so injector would be a good first thing to test.

Or do you suppose bad wire connection the one injector. Little over a week ago i replaced my intake manifold gaskets and had to remove my injector wires and fuel rail and injectors there selfs. Replaced it all even with new o-rings and worked fine up to a couple days ago. Thinking now it might be my mistake some how. The wire to injector looks secure. Also little over a month ago i used some fuel injection cleaner. Not sure how well it works. Also would a injector go bad just in between starts. What should i do from here guys?

Swap two injectors, if the problem moves, you know you have a bad injector. If the problem is still in the #5 cylinder, then the problem is somewhere else. Even if you don't find the problem, at least you've eliminated one thing from the list.