RX7 FD Full Bridge won't start

[DJ Boost]

currently on a Link G4+, previous motor was a street port.  Motor went out and swapped in a motor with about 500 miles.  Full bridge.  Car won't start and will only start on with aid of oil and starter fluid while motor is cold.  Hot start won't turnover.  Previous motor had minor cold and hot start issues (rotary life).  Once started we are able to drive around and car runs smooth except for one hole at 2000 rpms.  Tuner thinking might be a trigger issue.  Any ideas for cold and hot cranking?  Thanks

Log trigger issue hard to start red fd.llg daniel current briege.pclr

[Adamw]

If its been sitting for a while the first thing I would do is a compression test with a proper rotary comp tester.  Both the side seals and apex seals are pretty prone to sticking if they have been sitting for more than a couple of months.  Nearly always hard starting of a rotary is a compression issue.  There is no indication of a trigger issue in your log but it is only a couple of seconds of cranking so I wouldnt say that is conclusive.  

They also wont start easy if the plugs are fouled and it doesnt take much to foul them when the tune isnt spot on.  

What size injectors does it have?  Is the AFR in the ball park when it is running?

I notice also the trigger offset hasnt changed from the base map setting, this possibly means the tuner hasnt checked the base timing so make sure he has done that too.

[DJ Boost]

On 3/12/2020 at 1:14 AM, Adamw said:

If its been sitting for a while the first thing I would do is a compression test with a proper rotary comp tester.  Both the side seals and apex seals are pretty prone to sticking if they have been sitting for more than a couple of months.  Nearly always hard starting of a rotary is a compression issue.  There is no indication of a trigger issue in your log but it is only a couple of seconds of cranking so I wouldnt say that is conclusive.  

They also wont start easy if the plugs are fouled and it doesnt take much to foul them when the tune isnt spot on.  

What size injectors does it have?  Is the AFR in the ball park when it is running?

I notice also the trigger offset hasnt changed from the base map setting, this possibly means the tuner hasnt checked the base timing so make sure he has done that too.

When we did get it running, it was running smooth and AFR were fine.  Just start up, just won't go.  New plugs,  850cc primaries and 2000cc secondary.  My tuner never used link before and previous owner had a tuner who tuned the original map on Link.  Also had starting issues on original street port motor with original map.  I'm going to hook up a adaptronic and see if it starts.  New full bridge motor was hooked up to a adaptronic.  I'll see if i have same start up issue on adaptronic.  

Thanks for the response

[Adamw]

I had a quick look through your tune.  Nothing really jumping out to me that would cause a hard start but one thing I noticed in your tune that I dont really like;

The injector staging setup is pretty weird with the lockout at only 500RPM and sec injectors fully in by 40Kpa, this means the secondary injectors are on the whole time (maybe just above idle depending on PW).  Normally you would bring them in say above 3000RPM and maybe 80 or 100KPa.

 

[DJ Boost]

12 hours ago, Adamw said:

I had a quick look through your tune.  Nothing really jumping out to me that would cause a hard start but one thing I noticed in your tune that I dont really like;

The injector staging setup is pretty weird with the lockout at only 500RPM and sec injectors fully in by 40Kpa, this means the secondary injectors are on the whole time (maybe just above idle depending on PW).  Normally you would bring them in say above 3000RPM and maybe 80 or 100KPa.

 

Update, just swapped out the ECU to the adaptronic he had on the motor and it fired up.  It has to be some setting on the Link that's preventing it from firing up.  They are saying sell it.  I'm tyring not to and would like to stay with the Link.  Hopefully I can figure it out.

[Adamw]

In that case it sounds like it is tune related then.  If you can post a log of a start up with the adaptronic I can compare injector PW etc during cranking and maybe suggest some further changes to your tune.

Otherwise it really needs to go back to the tuner, get him to first fix the staged injection and confirm the trigger offset as I mentioned above, then mess around with the pre-crank prime (currently turned off in your tune) and the cranking enrichment to see if he can improve start up with those.  

A couple of other things I just noticed; 

1. There is only about 5 deg trailing split in the cranking region, open that up to about 15 may give it a better chance of catching.
2. Injector timing is set to start 360BTDC which is very early for a rotary, something like 90-150BTDC is more normal.  With the bridge port overlap I suspect you have a lot of fuel spraying straight out the exhaust.  

Also, although there is no sign of trigger error in your original log, your trigger arming threshold is a bit unusual.  I would suggest you change the 1000RPM cell in both the trig 1 & 2 arming threshold tables to 1.0V as below.

 

[DJ Boost]

17 hours ago, Adamw said:

In that case it sounds like it is tune related then.  If you can post a log of a start up with the adaptronic I can compare injector PW etc during cranking and maybe suggest some further changes to your tune.

Otherwise it really needs to go back to the tuner, get him to first fix the staged injection and confirm the trigger offset as I mentioned above, then mess around with the pre-crank prime (currently turned off in your tune) and the cranking enrichment to see if he can improve start up with those.  

A couple of other things I just noticed; 

1. There is only about 5 deg trailing split in the cranking region, open that up to about 15 may give it a better chance of catching.
2. Injector timing is set to start 360BTDC which is very early for a rotary, something like 90-150BTDC is more normal.  With the bridge port overlap I suspect you have a lot of fuel spraying straight out the exhaust.  

Also, although there is no sign of trigger error in your original log, your trigger arming threshold is a bit unusual.  I would suggest you change the 1000RPM cell in both the trig 1 & 2 arming threshold tables to 1.0V as below.

 

Damn, you the man.  I believe the trigger arming threshold did it.  It starts up and I was able to drive it.  Starts up hot and cold.  Struggles to start sometimes, I have to give it gas.  I took a log of me starting it cold and idling.  Maybe you can catch any settings that will help it start easier.  Once again it does fire up.  This tune is from my streetport motor.  Really hasn't been tuned on the new Bridgeport motor.  Thanks again, really appreciate it.

Boost startup idle.llg

[Adamw]

There is quite a bit of dwell scatter in that log and the RPM trace is a bit fuzzy which would suggest it is still not 100% happy with the trigger.  Can you do a triggerscope with it idling at about 1800/2000RPM.  How to do the scope:  https://1drv.ms/v/s!AiYbYlZQuRHPmidU5V2CmTcv6t2y?e=aEJ5S7

[DJ Boost]

19 hours ago, Adamw said:

There is quite a bit of dwell scatter in that log and the RPM trace is a bit fuzzy which would suggest it is still not 100% happy with the trigger.  Can you do a triggerscope with it idling at about 1800/2000RPM.  How to do the scope:  https://1drv.ms/v/s!AiYbYlZQuRHPmidU5V2CmTcv6t2y?e=aEJ5S7

I didn't get a chance to do the triggerscope because I got home late from work.  I did try to calibrate the timing.  Does the offset around the 223(the orange mark got close to the mark) sound right for offset?  Car wanted to start on its own after trying to figure out the offset.   

I must be doing something wrong while calibrating.   number seems high

[Adamw]

No 223 offset doesnt sound normal for an FD.  Although from memory I think the pulley can be bolted on wrong?  Its been a long time since I touched one but I think they have 4 evenly spaced bolts so it could be bolted on 90 or 180deg out?  

The Orange mark is 20ATDC so the best way to set the offset is to use the trailing lead for the timing light and follow the procedure in the help file on this page:  G4+ ECU Tuning Functions > Triggers > Calibrate > Rotary Trigger Calibration

[DJ Boost]

On 3/17/2020 at 1:05 AM, Adamw said:

No 223 offset doesnt sound normal for an FD.  Although from memory I think the pulley can be bolted on wrong?  Its been a long time since I touched one but I think they have 4 evenly spaced bolts so it could be bolted on 90 or 180deg out?  

The Orange mark is 20ATDC so the best way to set the offset is to use the trailing lead for the timing light and follow the procedure in the help file on this page:  G4+ ECU Tuning Functions > Triggers > Calibrate > Rotary Trigger Calibration

I was going off the wrong mark.  offset is -6.  going to try the triggerscope next

 

Hope it did the triggerscope correctly.  Thanks again for helping me.

Trigger Scope Log 2020 DJ Boost second crank.llg Trigger Scope Log 2020-03-18 7;50;00 pm crank.llg Trigger Scope Log DJ Boost.llg

[Adamw]

Ok, based on those scopes I would set your arming thresholds like this (both trig 1 & 2):

[DJ Boost]

On 3/19/2020 at 12:30 AM, Adamw said:

Ok, based on those scopes I would set your arming thresholds like this (both trig 1 & 2):

It started up much better now.  Have to give it gas but that has always been the case.  Took it around the block, much smooth and no hesitation at 2000 rpms.  I took a log.  Once again thank you.  Couldn't of done it without your help.

drive around block.llg

[the_mechanic]

Hey it has been sometime I haven't been in here

[the_mechanic]

Got the Link Water Temp sensor but it's much smaller than the one on my RX-7,  I want to know if you knows what part number I can order to fit an FD3S- RX-7.