Rough running with CEL 5/8 and fuel smell

Before anyone yells at me, I have done quite a bit of reading of the archives on CEL 5/8.

I drove the car yesterday almost 800 miles and it was flawless.
Drove it today about 15 miles and then stopped, engine off for about 20 mins. When I restarted CEL 5/8 came on and kept coming on and off the whole way home. Not a lot of HP drop, but it sounds like its missfiring and sounds funny now. More of a gurgling sound. Bypass valve? The car has test pipes and Tubi exhaust, so I understand it may throw codes here and there, but what would account for the rougher running? I also had quite a smell of fuel in the garage about 20 mins after I got home. Only 1/2 tank of gas in it now.

Nothing leaking, nothing dripping that I can see. The temp was normal while driving, no more than 160-170 or so.

Had a PPI friday and did look at the thermocouples, ECUs all looked fine. I did wash the car today but got very little water on the rear deck lid. I need to pull the codes yet but wanted to let the car cool completely before I restart it.

Any Ideas helpful.
Let the 348 curse begin on day 2?
Paul

 

There are no cats, running test pipes and tubi. Just trying simple things, I uncrewed the gas cap and tightened it back up with the car running, the idle dropped then went up about 200 rpm. the 5/8 CEL went out temporarily, then came back on. idled a bit rough and moved up and down from about 1000-1200 rpm. If i gave it a little gas the light went out, then back on. I shut it down after about 4-5 minutes.
I turned the battery shut off knob, but havent disconnected the battery yet until I get the codes out.
paul

 

Well the short answer is im not sure what "actually" fixed it. so i ran through all the connections first.
Pulled the MAF plugs, TPS plugs, O2 sensors, thermocouple, Cat ECUs and re tightened them. I disconnected the battery. Ran the main ECUs for codes and got 4444 on both ECUs which is a non error detected code from what Ive read. I need to get some 22 stabilant for the connections and spray them out.
I reset the ECUs and then restarted the car, adjusted the gas cap, topped off with fuel and it ran like a monkey on fire.
Fernando at Competzioni felt it was an electrical problem more than an engine problem.
I never got slowdown lights on either side and since the car doesnt have cats I was not sure if those would pop up anyway. The dash lights do work so Im confident the lights would have come on in a problem.
the 5-8 bank was definately out, but is functioning fine now. I may replace the cat ECUs over the winter and make O2 sensor grounds at some point.
Id appreciate any tips other members have that have run in to this problem.
Paul

 

thank you for letting me know, i was warned away from the dreaded dielectric grease but was told by a F shop to use stabilant?!?
Any other suggestions or just clean and clamp?
Nd