I recently began working on a car that was not treated well by its previous owner. The car turns over and can run on starting fluid. The fuel pump runs because I tested it with a hose and it spewed out fuel when the engine is cranked like the pump is supposed to. I tried to scan the car with a scanner, but the scanner cannot communicate with the transmission or engine. I would like to check the fuel pressure, but I am unsure how to go about that. I’m also wondering if the ecu could have a large role in the engine not being able to start because some wires were chewed by a mouse and I saudered them and covered them.
The scanner is supplied power by the vehicle so check your fuses under the hood and make sure that all of them are passing power. Since there are chewed wires there may be some you haven’t found yet. Pin 16 is usually the power pin of the OBD2 connector and pin 4 is ground. Check for power on those pins. That same fused power may also tie to the injectors.
Considering this is a japanese car, there’s a very good chance it’s not equipped with a fuel pressure test port
In that case, you’ll have to tee in, using a fuel pressure master test kit, such as this one
Even with the brief history you gave, this seems like an electronic issue. The ECU definitely can cause a no start. It sounds like you have spark, because it pops with starting fluid (ether). Are the spark plugs wet after you crank it, with no start? I’ll bet they are not, and for some electronic reason nothing is coming out of the injectors. That could easily be an electronic issue.
If you provide the model year, somebody here may be able to offer some guidance. On my old VW Rabbit I had to make up some adapters to T-in to the fuel line. On my Corolla I remove the cold start injector and use that port. You’ll need to buy some kind of fuel pressure gauge of course, absent some other way of measure the fuel pressure. I think some vehicles have a simpler method, but probably not yours.
One idea: Depending on the fuel rail configuration you may be able to remove the fuel pressure regulator, tap in there with some adapters you make up which include a place for the regulator in-line, and the fuel pressure gauge.
Possibly, but you’d need to confirm that with some measurements, rather than just replacing the ecu. My guess this isn’t an ecu problem. I think you are on the right tract looking for a fuel pressure problem. After that, clogged injectors or injectors that work ok but aren’t being properly pulsed. The injectors usually won’t pulse if the computer thinks the engine isn’t turning, so check your crank position sensor too.