I pulled the engine out of my 90 TT swap to rebuild it and put it back in. Now it’s not getting spark and I don’t know why. It has a new haltech ecu, ptu, spark plugs, coils. The wiring harness is old but it worked before I pulled the engine out and I didn’t do anything to it. I put a logic tester on it, and it is getting the 12v signal when you turn the engine over, but not the ignition signal. The ground wire is good too. The car ran before I pulled the engine out. I even put the old ptu back in to see if that was the problem but it still won’t start. I’m stumped.

Have you traced the CAS circuit? That's where the ignition and injector signal originates which then tells the ECU where the timing is.

It worked before but part of the rebuild was pulling it off and cleaning and painting it. Maybe I got paint somewhere it shouldn’t be although I made sure to cover the terminal. I’ll look into that. Thanks!

Depending on the year of manufacture, the locating pin may be worn, damaged, or missing, its a known issue with the CAS

http://www.jimwolftechnology.com/wolfpd ... GNMENT.pdf

Double check all the connectors make sure they are seated together properly, especially the three near the drivers side bay fuse box, CAS and PTU

Are all the three ground points secure to the plenum from the EFI harness? Should be 2 near the back and 1 on the lower frame rail near the AC comp.

I made sure all the connections and grounds were good. I pulled the CAS off to see if I could take it apart because I painted it and thought maybe paint got inside it and is interfering with it. It’s sealed pretty good though and you can’t take it completely apart without drilling out the screws. I also ran a file on the electrical connections. Still no luck. I bought a new CAS off eBay ($150 vs $280 from all other places selling it), but it’s coming from China so I won’t get it for about a month.

If its coming from China I'd send it back without even trying to install it. You're better off getting a used OEM one from a junk yard.