motor losing power at 2200 rpms
 

Hey everyone, I just bought a 1990 4 days ago. The guy i bought it from said it needed a new afm whick i purchased and installed. It ran great for 7 miles then started losing power (fuel or spark?) at 2200 rpms. Put a new tps thinking that would fix it but didn't. I have done the following, cleaned grounding points, dried all connections even though not wet, took ecu out took covers off and cleaned the board, plugs and wires replaced, and a few other small things. When it cuts at at 2200 it starts going again around 2000 rpms. I can't afford to buy parts that aren't going to fix it. It's a non turbo bone stock 1.6 manuel trans. Any help would be greatly appreciated. Thanks Russ.

I also checked timing and cleared dianostics. Timing was off 4 degrees and set back to 10 tdc.

How new are the plug wires? Still a single wire O2 sensor?

plug wired sre good and yes single wire o2. I talked to a guy yesterday that said it probably wasn't o2 but i got my suspicions

Timing off a tooth(s)?
How do you know the plug wires are good? Miata ones fail and still look perfect on the outside.

Better check for a messed up crankshaft