ok,I need help, 8mos+ Tbitz efi poor running issue

[juicersr]

I am finally crying uncle on this after 8mos + of of (intermittent) working with Tony trying to fix. My stock SC Tbitz EFI conversion ran flawlessly for the last year and a half since install. The car is kept under waterproof cover outside.

This saga started this past august after a full summer of EFI nirvana, i was out of town for a month, and while gone, a hurricane-like storm hit the coast. While the cover stayed on, there was some moisture in the cabin and course the engine bay. When i first started her up back then, it took a while to crank, then fired and ran fine for about 30-60 secs, then all went to he$$. Sputtering, stalling and basically running like crap. Sometime will hold an idle. Sometime will not. Sometimes revs smoothly 2000-5000. Sometimes misfires when i do this.

Tony has looked at the ecu parameters, and everything seems ok except no signal from O2 sensor. When the car is first cranked runs great for 30-60 seconds, then like a switch is thrown, begins misfiring, stumbling, etc. Have replaced wires, cap, plugs, rotor, green signal wire, cleaned all the CD box pin/other connections with vinegar solution per board. Installed a Fuel pressure gauge in-line, good Fuel pressure.

I took the distributor out the other day, to basically look it over and 1/3 cup or so of water spilled out when i turned it over. Ah! this is the problem it thought. Plugged it back in, it fired up crisply ran awesome for full 1-2 minutes (whoohoo i thought!), then same crap. She seems to idle, sometimes smoothly, sometimes misfiring. When i try to drive around the block, it's like only 3 cylinders are firing. Any thoughts? (PS, anyone have a spare CD box that could borrow to check for this) Thanks to all

[sjf911]

That sounds like one hell of a storm to get water into your dizzy. Makes me glad I don't live in Texas anymore. Weather in the NW is much better. Have you checked the MS ECU (I assume it is under the passenger seat) since you had water in the cabin.
My car is currently down for an extended period for an overhaul and MS-II EFI conversion. I can loan you my CD box for a while but it will take some time to get it to you.

[juicersr]

Steve, thanks for the offer! PM sent. While i didn't send the ecu to tony, he looked at the MS readings, etc and are ok, and has assured me that the ECU either works or doesn't, and that if that were the issue, car wouldn't run right at all. I have the ECU in a sealed, almost waterproof box under the passenger seat. No standing H2O after storm, just really damp.

Anyone with ANY other ideas. Am willing to entertain any crazy suggestions on this one. Does it sound like an intermittent CD failure? Could standing water in the dizzy have totally screwed up my almost new (year old) distributor. Getting no o2 sensor reading, but that wouldn't make the car run rough or misfire, would it?

[jpnovak]

I think its ignition related. I suspect water in the plug wire connections to the coil and dizzy. Look for carbon trails on these parts that shows where the water allowed the system to discharge the spark when it was wet.

solution: pull all the plug wires and coil wire. clean well. reinstall with Dow 111 (silicone) or suitable dielectric grease. If your plug wires are old you may consider replacement.

[TimT]

Getting no o2 sensor reading, but that wouldn't make the car run rough or misfire, would it?

Yes it would if you use the o2 sensor output in closed loop running.

[juicersr]

Ok, will clean and spray the f$$$ out of all ignition components (again)

Tim, so the 02 sensor really doesn't play a role when the car is stone cold? Does the MS ignore it in warm-up mode and only relies on input from it when to car is warmed up after a minute or so?

[TimT]

Tim, so the 02 sensor really doesn't play a role when the car is stone cold? Does the MS ignore it in warm-up mode and only relies on input from it when to car is warmed up after a minute or so?

I am not familiar with the MS software... and I dont know how you have your system configured.. but if you have your o2 sensor contributing to any of the tuning/running parameters.. and the sensor doesn't work.. then you may have issues..

You mentioned getting no o2 sensor reading... hence my reply..

[sjf911]

You need to set your EGO step value to 0 in Megatune to disable closed loop function of the O2 sensor. MS will disable closed loop at warmup and I believe also at WOT. It its hard to imagine that this would cause as severe an issue as you are having. More likely your O2 sensor is bad due to poor ignition and excess hydrocarbon in your exhaust for the last few months.
I have my CD out and boxed ready to ship to you. Try the above recommendations and if they fail to help I'll get it in the mail. Don't worry about reimbursing me for shipping. Return the favor to another pelican some day.

[juicersr]

Steve, thanks a million. Went ahead and ordered a new 02 sensor. Recleaned everything last night and shot everything with dialectirc grease... same. Am really suspicious about intermittent CD failure at this point as everything else seems ok.

[sjf911]

CD is in the mail. Should arrive monday.

[BoxsterGT]

sjf911......

Is this what you are working on?



It runs great w EDIS.....

Len

[sjf911]

Len, almost exactly. The only difference is I am using a 3.2 intake and fuel rails. Is that a TBitz setup? Also, where did you source your wires?

[juicersr]

Thanks Steve! Len, would ya mind sharing some specifics (wiring of the EDIS panel, etc) for those of us contemplating this. I for one may be going there sooner than i thought after all this ignition headache. Any problems with getting the set-up sorted? Did you use the Going Super Fast pully set-up?