Engine Performance problem
1990 Mazda RX7 Two Wheel Drive Manual 144000 miles
My 1990 rx7 will not start - It had a thermostat housing leak - tried to repair it - broke off one of the bolts holding the housing and then broke the ezout too. Tried to drill it out but kept burning out the bits. So it sat idle in the garage for 5 years. Finally found a special real hard steel bit and got it out and back together.
Now it won't start. Replaced the fuel filter and pump because the pump wasn't working, could not get any volume from the fuel line or hear it whirring. Also noticed the fuel guage showed empty. (I did put 4 gals of gas in and it still did not register.) When I removed the pump assembly from the tank, it was crudded up -- looks like the rubber gasket holding the electrical pump to the assembly dissolved into a tar-like sticky goo. I cleaned the tank as best I could with a wooden scraper. Mostly the crud was inside the fuel tank baffle.
The new fuel pump works and I get fuel going through the system, but the fuel guage still shows empty. Jumpered the yellow pump check relay connector to check flow and noticed that the pump never shuts off, even after 5 minutes. I can feel the fuel flowing in the large fuel rail for the time that it's jumpered. It feels like the pressure regulator is not working. Maybe the crud got to it too and clogged it up.
Questions: Since the requlator is not replaceable by itself (its part of the rail itself) and the whole rail must be replaced (And there are 2 and quite costly), is there some kind of test I can do that would definitely point to the reg as the problem?
When jumpering the yellow connector, what should make the fuel pump shut off?
If I take out the spark plugs and put a little gas in the opening and then replace them, should the engine fire a little thus saying that maybe the injectors are bad or there is too little fuel pressure?
Btw. I have good spark. Checked that the usual way. When I checked the spark plugs, they were pretty fouled and had to be cleaned. I also replaced the fuel pump with part # n370 while the original was an N351.
Monday, August 23rd, 2010 AT 4:46 AM