I just finish building a MS2, and wen't out today to try it in the car for the first time. I got it hooked up, and tried to start the car. The engine cranked for a short time, and then there was a loud THUNK. This noise was repeated on attempting to start the car on the stock ECU shortly thereafter. I also tried turning the crank by hand too, it won't budge.

I was certain to double and triple check everything while building the MegaSquirt, it was built from this guide: 90-97 MS2 sequential | Frank's Westfield MX5 90-97 MS2 sequential |

At this point I'm trying to figure out how I screwed up on the MegaSquirt build and how much damage I've done to my engine...

Any help is very much appreciated

 

It's a non-interference engine. You couldn't have done much damage. Did you do anything else between when you had the car running last and when you installed the MS?

 

Not a single thing. I literally just swapped in the MS, plugged it into my computer, and tried to start the car.

 

Maybe pull a few spark plugs and take a peak to see if the cylinders are full of fuel........

 

Good call, cylinders 2, 3 and 4 were flooded. Any idea why the MS would do that?

 

Do you have an early car? If so, did you unplug your TPS?

 

If you don't have a 1.6, then something is wired up wrong, or your crank settings are waaaay off. You might want to verify that your injectors aren't spraying with just the key in the on position. I'd imagine just leaving the spark plug out and turning the key to "on" you can smell if they are open. If not and it's flooding during cranking you need to adjust you settings. This is all assuming it's not a 1.6 and you needed to unplug the tps.

 

Why was cyl1 not flooded (just leekdown or something different with that injector)?

 

It's a 96, so it can't be the TPS. I'll check if the injectors are spraying with the key on. My cranking PW settings are just the default values:

10.0 326
30.0 301
50.0 276
70.0 251
90.0 226
110.0 201
130.0 176
150.0 151
170.0 126
180.0 101

I'm not sure, the cylinder looked dry. I'm inclined to believe something is wrong with the wiring.

 

Also, injectors aren't spraying with with the power on, jumped the fuel pump to be sure.