[Ron]

Hello All,
Got a question, My Z car runs on 3 cylindars,Sounds strong but only 3 cylindars Why the vehicle idles, I disconnect the rear fuel injector plug #6 the vehicle idles the same why disconnecting the rear connectors. Until i hit the front ones then the car bogs down again so basically the rear section is dead thought it was the wire. i reversed the wiring and it worked fine in the front. Tommorow i will pull injectors out of intake to check for fuel delivery. Any suggestions.......

Thanks
Ron

 

[yo2001]

I think one of your injector is shot. One injector will knock the other two out of wack. Screwdriver test all the injectors and find your bad one

 

[Kevin 280/300TT]

The answer is...

I've seen your problem described, but I can't remember where! It may have been the FSM, the FI manual, of the Z therapy video. There is *something* that controls power to 1-2-3 inj, and 4-5-6 inj. You test it thru the 1 and 4 circuit. If you lose 1 or 4, you lose all three. Its not the injector...may have been the dropping resistor. I'll look and let you know.

Kevin

 

[79-280-ZX]

Kevin is on the right track. Dropping resistors 1 through 4 are in one module 5 and 6 in a separate one.

Before you start ripping things apart put a long screwdriver on the metal body of each injector and put the other end (handle) in your ear. You will hear a clicking sound each time the injector fires. Check that the Injector connections are all clean. If you hear nothing check the connections at the dropping resistor.

If you still get nothing then disconnect the negative battery terminal and then remove the connector from the ECU and clean the connections. Put a small amount of dielectric silicone grease on the ECU connector and reassemble to the ECU. Reconnect the battery. Repeat the screwdriver test.

If it still runs bad check that you have 32 PSI of fuel pressure at idle, with a fuel pressure gauge, now pull the vacuum line off the Fuel Pressure Regulator and the pressure should rise to 42 PSI. Put the vacuum line back on and hit the throttle, the fuel pressure should rise again.

If you get this far then one of the injectors is probably plugged up. To find out pull a spark plug wire with the engine running one at a time, if the engine runs worse that is likely not the culprit.

Wayne Monteath
Masham, Quebec.