88' 6000 Engine Problems

[reibukan]

hi, I have a 1988 Pontiac 6000 LE with 2.8l V6 engine...has failed smog in CA and has been taken in and diagnosed 3x by local shops....one shop said has a code 64 - Map sensor issue ; other shop said bad ignition coil.....I replaced the bad ignition coil ; did not fix issue(s)...
This ALL started when I let my girlfriend drive it to work......but in her defense..the car had a bad/cracked spark plug wire which probably arced and shorted out the ignition coil.......NE wayz....the GF called me from work ; said it wouldn't start or turn over......had her boss look at it ; he messed around in engine compartment for a while ; then found out the fuel pump fuse in glove box was loose......he pushed in and car started.........then car started having driveability problems.....loping and knocking and sounded like a cylinder or two were missing......I have NOT replaced the MAP sensor yet ; is that correct? is it MAP or MAF?...... NE wayz.....car had no power ; took long time to get up to speed from a stop ; and chugs really bad.......
I have replaced the spark plugs (cheap AC delco's I gapped myself) ; the spark plug wires (Bosch from Autozone) ; replaced ALL of the 3 ignition coils (www.rockauto.com cheapies $17) ; and still having same issues...HELP!
I'm going to replace the spark plugs again with either NGK or Bosch 4304's hoping there was an issue with way I gapped them or something.....and gonna put new air filter and maybe PCV valve in too.......what else should I do ????
thanks

[maxwedge]

How about finding what the problem is " chugging" means all things to all people, from here no way to tell what your symptoms really are, do you have misfires? Is it actually running on 6 cylinders? Check the injector fuses, there is one fo each bank, you may be running on one bank of injectors, but onsite diagnosis is required here. Is the fuel pressure up to par?

[reibukan]

"How about finding what the problem is " chugging" means all things to all people, from here no way to tell what your symptoms really are, do you have misfires? Is it actually running on 6 cylinders? Check the injector fuses, there is one fo each bank, you may be running on one bank of injectors, but onsite diagnosis is required here. Is the fuel pressure up to par?"

hi, thanks for the info......the chugging is kind of vague ; that's why I'm posting to get ideas what could be causing it.....(just a note: I have had new Magnaflow Catalytic Converter and Muffler put on because last set got wasted when this issue started) ; The Misfiring I guess you could call it caused high pressure "chugging" which in turn blew out the Cat ; and put holes in my muffler..........but those were replaced with no effect on the issue(s).........when I first took the car in; the mechanic hooked it up to a handheld SnapOn scanner......said it got code 64----I then took it to local place called "Made In America" ; and they said fuel pressure is ok ; but one of the Ignition Coils was bad ; so the car was running on 4 cylinders......
I replaced the bad Ignition Coil myself--no change---Took it in again to same Company ; but different location---they told me another,different Ignition Coil was bad....so I replaced the rest of them (3 in all) ; used same brand---no change to speak of---Except the car started to die on me--found out had a bad Negative Battery Cable connector--replaced that and car stopped dying on me.
I'm trying not to drive the car so it doesn't blow out my new Cat and Muffler which were very expensive----I did consider getting that shop to replace my Ignition Control Module since I guess that could be bad---but it's real expensive and I'm on Unemployment right now--so trying to keep the repair costs low if I can.......thanks for everybody's help---PS: should I replace the MAP sensor next? Since it threw that code???

[reibukan]

PS: where are the Injector Fuses located? I will check them if I can find and access them.....anybody have any pics of where in engine compartment they are? If not ; a description should do.....Oh, one other thing......What are everybody's thoughts on the best Spark Plugs to use on this engine??? I know I want to use ones that are already pre-gapped at the factory- like the Bosch 4304....they are double electrode and Platinum.....with a tapered center dealy-bob electrode thing-(and they're a good deal in the 2-packs at Walmart)....I do have a Torque wrench so they are being put in at correct ft/lbs.........and should I use those little grease packs they sell at the Auto shop counter for the threads? I didn't last time; hope these other ones aren't hard to take out because of that...

[maxwedge]

First thing to do here is confrirm you are getting spark to all 6 cylinders, use a spark tester or hold the plug wire off the plug near a ground, if all have good blue spark then you have to confirm the inectors are working. Post back results, any plug when new is acceptable that is not your issue here, assuming the wires are in the right order, and no one dropped the plug. Injector fuses should be in the under hood panel.