No Start Troubleshooting
 

Hey everyone, I'm looking for some assistance in troubleshooting a no start situation with my project.

Relevant information:

1974 REPU

13B-REW with REPU front cover; stock ports, stock fuel rails with 1300cc bored out secondaries. Walbro GS392 fuel pump.

Verified compression with Rotary specific compression tester; 90-93psi on all faces.

Haltech PS1000 with Haltech terminated loom harness and fuse/relay block. Using the built-in MAP sensor on the PS1K.

LS1 Direct-Fire ignition system. New NGK 9's all around.

FFE Hall Sensor trigger kit.

What's happening:
Engine will crank over but doesn't start. Does not sound like it wants to start or will nearly start- just cranks. During cranking AEM WB02 does not read anything (max lean).

What I've tried/verified:
I am essentially running the Haltech base map for the FD with the trigger and ignition settings changed for my setup.

I have 12v to the coils and injectors.

Got it to run off some starter fluid for about 5-7 seconds.

Fueling; I made big additions to the fuel base map and can see smoke/excess fuel pushed out of the exhaust and the AEM WB02 will read down to 14:1-16:1 during cranking with this "excessive" amount of fuel added to the fuel base map. Fuel injectors appear to be working.

Injector duty is around 2.5-3% while cranking. Injector pulse around 5.5-6.6 off base map setting. I've gone as little as 1.5ms to as much as 22ms of injector pulse width when I got the 14:1-16:1 AFR reading while cranking.

Timing: I have verified all 4 coils are firing with a timing light and that I have the firing order/coil assignment correct. I've tried everything between 5-20* of ignition timing advance while cranking with no difference.

Trigger/base timing: Here is where I'm not 100%. As said I am running the FFE Hall Trigger kit. I have the REPU eshaft hub on the 13B-REW engine with FD crank pulley flipped backwards. Because of this setup there is no timing mark and the pulley/trigger wheel will align in all 4 positions. I used the stock REPU pulley as reference (that has timing marks) to align what I assumed was the TDC indicator on the FFE trigger wheel when installing.

This is what the trigger wheel looks like with the front rotor at TDC:

https://cimg4.ibsrv.net/gimg/www.rx7...0fce0db79a.jpg

https://cimg3.ibsrv.net/gimg/www.rx7...90d73f26ae.jpg


I manually aligned the rear rotor apex seal to point in-between the trailing and leading plug and then marked the pulley as TDC to the indicator with the stock REPU front cover. With the engine cranking and timing locked to 0*, I moved the trigger offset value in the Haltech until I got the timing mark lined up. I ended up at a trigger offset of 143* which seems off to me. Most people with this kit use a value of 90* but I understand my setup is a little different. I'm not 100% if I followed the zero timing procedure correctly or not.

Since making this adjustment to the trigger offset I can not get it to run of start fluid as before. Still doesn't sound like it even wants to fire while cranking. I put the trigger offset back to 90* and it still won't fire off starter fluid as before. Is it feasible it could run off start fluid with the trigger offset off by 53*?

What else can I test and troubleshoot? Did I mess up the base timing reference and trigger wheel offset? :scratch:

Thanks for any assistance.

Minor update:

Went to try and re-verify timing and my timing light was showing no output/not flashing on any coil. I was puzzled as it this was just working and nothing had changed. Check fuses all good. Verified power at every coil on the harness. Suspecting my cheap timing light, I pulled the leading plugs to have them arc to the fender. The L2 plug had a very strong arc but the L1 plug was rather weak. Switched plugs and the weak arc followed the plug- bad plug. I put it in the T1 position and verified a strong plug is now in the L1 and L2 position.

I sprayed some starter fluid in the TB elbow and it fired up for about 4 seconds. I was then able to crank it while spraying start fluid in the TB and it would fire, and I could keep it running (roughly) while continuously spraying start fluid in the TB.

I then figured it must need more fuel so I added a large amount (from about 6ms of injector pw to 25ms) to the fuel base map. I also changed the trigger offset back to 95* as I don't trust my timing light. It sputtered and ran for the first time without the aid of start fluid, but died after about 15-20 seconds, but actually ran. I added a little more fuel to more areas of the map it would trace to once running and it started and ran again for another 20 seconds.

I added even more fuel (probably 32-35ms now) and it wouldn't start and was smoking quite a bit of fuel vapor and the AFR was showing about 11:1 during cranking. I may have flooded it and pulled fuel back out and couldn't get it to light again, with or without starting fluid. It seems very inconsistent. And I don't trust my timing light or how the trigger offset is.

Thanks for any input!

mate just so you know my FFE trigger offset is 59.

If you needing to spray in more fuel then I think their is injector issue or a wiring to the injector issue.

(I once had P1 and P2 plugs back to front - couldnt figure it out for ages as would run and die, start die, start run die.)

Thanks for the reply.

I have checked injector and coil wiring from plug to ECU plug and have triple checked they are in the correct spot.

I did go through checking TDC one more time I am pretty sure I had m TDC mark off. I realigned the trigger wheel and referenced TDC marks on the stock REPU pulley so I feel confident I have that accurate now.

Will try and test fire later today.

Minor update; found the previous owner had modified the fuel injector harness and it was incorrect. I fixed and it now the wideband reads at a much more reasonable fuel injection pulse width. But still no start.

I have verified TDC at least 5 times and I am positive I have it right.

I did some remote tuning with a friend and he noticed the missed trigger/tooth count was quite high (around 15-17 during cranking). Also, in the trigger setup page, the Home Window is at 16 and Tooth count is 1. These boxes are greyed out and I can't change them and they remain the same regardless of the trigger wheel I select. The setup page on the FFE website for the PS1K ECU shows a Home Window of 24 and Tooth Count of 24. I am wondering if this has something to do with my issues and how I can edit these settings?

I have an FC CAS coming tomorrow to try and eliminate issues.

Thank you for any help or guidance.

yeah I dont know why yours has 2 missing teeth?

I have the FC one and only 1 missing tooth.



https://cimg7.ibsrv.net/gimg/www.rx7...e098173eb5.jpg

https://cimg0.ibsrv.net/gimg/www.rx7...c44ae7c516.jpg

(thats mine above with 1 missing tooth configiurations - no errors)

change yours to 24 teeth and 2 missing tooth

He should have the 36-2-2-2 Renesis wheel for use with the Sport ECU. It's the only FFE wheel that will work with that ECU.

OP, post your map.

I have attached the two ECU maps, one for the FFE hall trigger and another for an FC CAS. The maps might be a little basic since I've been disabling a lot of corrections to eliminate variables.

I got an FC CAS and installed it per the FSM and wired it up as per the Haltech instructions. I get RPM signal and everything looks right but still no start.

I loaded a friends known good calibration from his car that uses a PS1K and an FC CAS and still no fire.

I suspected faulty primary injectors; I pulled them out and cranked the engine while watching them and both primaries appeared to spray excellent, no leaks and both were functional.

So at this point I have tried;
FFE Hall sensor
FC CAS
I have spark on all 4 coils, all coils are wired to the correct plug from spark plug to ECU pin
I have the fuel injectors wired correctly from injector clip to ECU pin ad I have verified primary injectors are functional and working
It will sputter and run briefly while on starter fluid
Fresh fuel in the tank with a clean filter, brand new pump, engine has good compression.

Only thing I haven't tested (because I don't have a gauge or sensor) is fuel pressure. I plan on getting a sensor and wiring that into the Haltech this week. I'm running stock FD rails with the stock pressure regulator on the secondary rail. I have fuel flowing to the rails and fuel returning to the tank.

Any help is greatly appreciated.

Dave

Give this a try.

Thanks for everyone who weighted in on this, I finally got it started today.

As is the case with probably most of these, it was a mechanical problem. I pressure tested my intake system and found 3 large vac leaks. Fixed them and it started up almost instantly and idled on its own. Everything looks great. Now for some fine tuning, a custom 1 piece driveshaft and this BW S366 REPU will be ripping up the road soon!

glad to hear its sorted

You still need to zero out that MAP compensation table. The way you have it setup will make for some odd fuel mapping.