Jakek93

I was curious if there are any rotary gods that could give me some pointers.

I have a FC3S Turbo 2 RX7 that is currently tuned on MegaSquirt. I have walked through Aaron Cakes walk through and double checked the wiring from the previous owner. Currently the car is tuned on the walk through's base settings just in order to achieve idle.

The car has the following modifications to the fuel/air system: Wideband, Large Street Port, Boost Gauge, FMIC, 850CC Secondary injectors and is running an MS3X.

The issue is that the car floods after each start up, Manually deflooding (removing spark plugs and using ATF to build compression) the car allows it to start and run for about 20-40 seconds before it dies. Pressing the accelerator pedal in an attempt to keep it running, it bogs out and dies.

I currently do not have a log file to check as it dies before I was able to get one started by myself. Thank you in advance for the assistance and I apologize if this was posted else where already, I am new to the site.

Aaron Cake

iTrader: (1)

Sounds like the map is excessively rich. A datalog would help immensely. 40 or seconds is significant as that is when the after start enrichment probably ends.

What was the wideband say as it begins to flood out?

Jakek93

I would be lying if I said I wasn't a bit star struck! Thank you for your reply and thank you for the excellent write up and overall guidance you have given the community!

I have attached a datalog that I was able to get tonight. I am not the best at reading them as of yet, please forgive me if there is an obvious issue that I have overlooked.

The wideband is reading at 12.5 it begins to die and then 13.1 as it dies.

lduley

iTrader: (1)

Your thinking backwords then, 13.1 is lean, the car is leaning out then dieing. Are you positive there are no vacuum leaks? I'm no tuner, but i believe it should at least idle at 13.1

Jakek93

I believe target stoichiometric Air/Fuel ratio is 14.7:1. 13.1:1 is a bit more rich and 15.1:1 would be more lean or so I thought, I may be incorrect though.

I do believe that the car should idle around 12.5-13 though without dying. Looking over the data log again though and doing some research it looks like the car may have a vacuum leak. I attempted to do the math to convert the kPa to in-HG and it was reading at around 15-18 in-HG. Which from what I've read should be fine?

I'm not sure if I am reading the data log correctly though.

lduley

iTrader: (1)

thats getting into territory I have NO clue on, but around 13 it should run unless you have a vacuum leak, or your wideband is reading wrong. Really if you have a vacuum leak, on your log near the point of the engine dieing the A/F should start leaning out (13 to 14+).

Wish I could be of more help, I know Aaron only gets on on weekends, so if you're waiting for his help, just be patient

Jakek93

I'll be rechecking for vacuum leaks and re-examining the car this weekend just to make sure. I wont have a chance to get into it again until this weekend though.

Jakek93

I think I may have found the issue. It looks like the BAC valve vacuum line is not connected. The previous owner made a custom inlet duct and there is no way to connect the BAC vacuum line. Is it okay to cap it or should I find a new piece of piping to allow it to connect? All the emissions have been removed.

Jakek93

My bad it was part of the stock intercooler that had been fitted on to the FMIC but it had been clamped and JB welded shut. I found that I had a spare section that should work.

I'm going to try it out and see what happens after I get the vacuum lines from the auto part store down the road.

Jakek93

Well I removed the UIM and replaced all the vacuum lines and recapped everything that was left over from the emissions removal just to be sure. I also went through and reconnected the BAC valve and tightened down all of the intercooler piping.

The car sounds better now but it still will not start, despite it trying real hard. I did not try and use ATF to get it going tonight.

I'll be doing a compression test tomorrow but I'm pretty out of ideas. I have a set of spark plugs coming also just in case.

lduley

iTrader: (1)

I personally wouldn't use ATF, not good for the oil control o-rings from what i've read on here

And i agree with a compression test, never a bad idea to know and to rule it out, but i have a feeling it may not be your problem

Aaron Cake

iTrader: (1)

Looked at your log. Can you also post your map?

Around record 436 something happens. The AFR leans way out to 14.8 or so. I'm assuming the afterstart enrichment stops. Once it hits that AFR, the BAC ramps up to compensate, the engine wanders around a little with you trying to compensate via the throttle, then dies.

But more importantly, there is constant sync loss from the CAS throughout the datalog. Reason 11, which is that the ECU is losing count of the NE wheel.

How is the CAS wired? Needs to be shielded cable, grounded only at the ECU end. Check the connectors at the CAS and make sure they are clean and tight. If you have another one, swap it in place.

Also the pots within the ECU need to be fully counterclockwise.

Jakek93

Thank you for taking a look at the data log, I had completely missed the AFR spike and the Lost Sync.

It looks like the shielded cable had been cut and re-spliced together and I did not notice when I bought the car. I will rewire it today and make sure that the CAS is installed correctly. I do have a spare CAS just in case.

I'll double check the settings on the ECU itself as well.

I have attached the map.

Jakek93

Looks like the wiring supplies I'll need are going to have to be ordered in. I'll have to wait until next weekend to continue.

Aaron Cake

iTrader: (1)

That appears to be just the VE table. I'd like the whole .MSQ file.

Jakek93

Whoops! My bad, sorry this is my first project using a standalone and attempting to learn to tune.

I have now attached the full MSQ file, it should be pretty close to your walk through base settings.

Aaron Cake

iTrader: (1)

I looked at your map.

Turn off PID idle control for now.

Also turn off PID EGO control.

Calibrate your TPS.

Running any better?

Also, you need to fix that CAS or it will never run right however my suggestions above might get it running better now.

Basically I'm seeing a closed loop idle trying to maintain the idle while EGO correction is leaning the engine out to 15s for cruise.

Jakek93

Thank you so much! I will make those corrections today.

The wiring supplies came in today, so I'm just getting started redoing the CAS and setting everything up. I'll let you know what happens once I get the wiring fixed tonight!

Thank you so much!

Jakek93

Well I spent most of the day cleaning up the wiring and running the new CAS Shielded wire. I had to replace the connector on the CAS side and fitted the shielded with a new connector as well.

The problem originally was that the shield wire was grounded to Pin 2 instead of the actual conductor itself.
After re-running the wire, I attempted to start the car and it would attempt to start and backfire. When I looked over at the lost sync count it was still climbing and had reached 6 over a period of cranking. I tried to run a data log but the car battery died before any real info could be gathered. The 15 second log did show 2 missed counts but did not give a reason.

I'm at a bit of a loss again, and my weekend is over unfortunately. The harnesses are about out of wire to work with if its going to need to be redone. It may be time to pull it out all out and redo it all.

Jakek93

Its been several months as life got in the way but I've still been unable to get the car up and running.

At this point I pulled all the old wiring out for the megasquirt and rebuilt the fuse panel for the MS to the specifications in Aaron's walkthrough. As I went through the car there were several issues with the wiring that I had not noticed before. I replaced the CAS and ensured that it met the specifications in the FSM.

Everything looked good and I attempted to start the car and it fired up much easier than before...for about 6 seconds. After the start up, the Tach is now dead and the ECU can not see the RPM signal. The fuel pump is still working, along with everything else on the ECU other than the RPM signal. It doesn't seem to even try to start but it continues to crank.
i double checked the wiring and tested the CAS, everything looks to be good but I can't quite pinpoint where the fail is at. Any tips would be awesome, I'd like to hopefully have it running by the weekend.

Jakek93

Finally got it to get up and go. There were a few lose grounds that needed cleaned up.