Turbo install, wont start now
 

I recently installed my turbo setup with rx-7 460cc injectors and can not get the thing to run, at all.

The car is a 91 with 1.8 swap, running MSPNP (MS1). all 1.6 electrical

prior to the install the car ran flawlessly, i've been screwing with my cranking PWs and fuel_req to get it to do anything and it just continually cranks, occasionally a pop here and there but not very often. I swapped ignitors, coil pack and plugs

Just for kicks when i initially put everything on, i tried starting it with my old map and i had better luck with that but still no go... It would burble and try to start, but after screwing with my settings i get nothing.

I attached my msq file that i'm using, any suggestions?

Did you also do a timing belt?

no only thing i did engine related was the turbo install

you also did injectors. any chance you swapped the fuel lines?

I marked them when i took them off, so i put them back on the same way they came off.

I'll have to double check them just to be sure.

What changes did you make for your larger injectors?

to start you should have taken your old map and changed:

Req Fuel
accel wizard ms
cranking ms

Scale them accordingly. Check useful saved posts for a calculator to scale them
Everything else I think is in % and shouldnt matter

Warning: i didnt open your msq

Maybe bad injectors? I remember doing a motor swap on my brother's car, we started cranking it over and it never started. We tried a few things and nothing worked, so we pulled the fuel rail to check the injectors and only 2 were squirting. Switched out injectors and everything was perfect.

After some more testing, i get spark when i initially turn the ignition on, and thats it. Occasionally i get a spark maybe every 5 seconds or more of cranking.

In megasquirt, i'm not getting any cranking RPM either. wires & fuses are OK, grounds are ok.

I'm thinking possible bad cam angle sensor?

swapped out CAS with my other miata, a known good working one and still does the same thing.

Definitely not getting a consistent spark but im not sure why... Switching to another set of coils gets my cranking RPM though


Im having trouble attaching the datalog as an attachment...

Make your life easier.

Put your location in your sig.

car was running MS before turbo install?

so the only real change was the 460cc injectors?

Yes that is correct. Ran 100% fine prior.

Like I said the weird thing is that when I initially tried starting it before making tuning adjustments it was trying to start but clearly getting too much fuel. Now after the adjustments I get very inconsistent / no spark, really only when I turn the ignition to ON I get the initial spark

I think there's nothing wrong with your ignition system. If you're not seeing an RPM indication in Megatune, that immediately tells you that the problem is related to the CAS signals.

Since you've swapped out the CAS, we can probably rule that out. I would figure out which wire(s) you accidentally pinched / broke / disconnected during the turbo install and fix / connect them.

For starters, pull the connector off the CAS and measure with a voltmeter between the black/green and white/red wires at that point. You should see +12 here both in the "Run" and "Start" positions.

If no, then diagnose that circuit. You can start by checking for +12 from white/red to ground, and for continuity between black/green and the chassis.

If that's good, then you can check for voltage between the yel/blu wire and ground and between the white wire and ground, with key in "Run". These are the two signal lines between the ECU and the CAS, and the ECU should be applying a pullup voltage to them. I don't know whether the MSPnP is internally wired to pull them both up to +5 or whether one will be at +5 and the other at +12. But you should see one of those two outcomes. If not, you have a problem on those wires.

Whatever you do, don't get frustrated and start randomly checking / replacing other things. Your problem is somewhere between the CAS and the ECU, inclusive. Not with the fuel system or the ignition system or anything else.


edit: it could also be that you've somehow hosed up the software config inside the MS itself. Could you pull an MSQ file and a datalog of you cranking the engine for a few seconds?

Well, last night the cranking RPM would be kind of off and on. Definitely not consistent


Heres a copy of my datalog, its kind of long as i let it log for about 2+ hours or so i couldn't upload it through the website (its slightly over 3mb)

http://www.mediafire.com/?sy9b1vxs4eon1nx


The MSQ i was using is at the top of the page on my first post.

I was thinking of just reloading the firmware / basemap and starting from scratch, after i check the integrity of the wires to the CAS


Thanks for the help so far!

wow

Thanks for the help Joe, the problem was when i extended the wires for the CAS when i did the 1.8 swap, one of the wires worked it way ever so slightly out of the crimp connector so that when the engine torqued over it would pull it in and out which is why it was so inconsistent.... she starts and runs now!

:)

Now the fun stuff begins...

Glad to hear everything is working right!

good luck!!