New ECU and now leaking fuel on intake...

[TUI2I30]

ignore this post, go here (page 2) instead.

http://www.dsmtuners.com/forums/showthread.php?t=197760&page=2&pp=25

I am picking up my talon today, it has been sitting for a few months. The car's old ECU had the capacitor problem and fried the original ECU. I got a new ECU for the car yesterday and installed it. Now while the car is idling it is dumping fuel on the intake manifold and running pig rich. I believe that it could be a stuck injector or relay. It could also be the ECU (I have a warranty) or the SAFC settings. The fuel pressure regulator is set at 42lbs at idle. Any thoughts on this would be helpful. I'd really like to drive it back home instead of trailering it. Thanks in advance.

 

[TUI2I30]

The issue cropped back up!! I pulled the wires on the injectors and did a resistance check on them. I got a resistance reading on the #4 injector connector and nothing on the other 3. I pulled the ecu out of the car and with the help of the service manual located those pins on the ecu.. same result as test at the connectors. I was told that this ECU ran in another car, doubtful!

I am assuming the fact that I got a resistance reading on #4 is not good, can anyone verify this for me? I am now looking for another ECU.

and I still sit in my car in the driveway with tags on it, pretending I am driving it! oh how nice it is to dream!

 

[steve]

How did you measure the resistance?

Steve

 

[TUI2I30]

How did you measure the resistance?

Steve

With a multimeter on both wires at the connector and ecu. I was checking to see if the wires were possabily shorted and discovered this instead. Once I found this, I wanted to see if it would read the same at the ecu and it does. Pins 61(#4 injector) and 58(Stepper motor coil a1) on the ecu gave me the same reading that I got at the injector plug. I tested the other three pins for the injectors as well as the other three pins for the stepper motor coil. All with the same results as under the hood.

Also, I checked it again at the connector with the ecu out and the circuit was open on all of the injector connectors.

 

[steve]

OK, lets try this again. You measured the resistance between the two pins on the harness in one case and the other between the ECU pin and what? What value did you measure?

When I measure the resistance between the injector outputs and ground I get about 0.5 ohms.

To check the injectors and wiring, First you would measure the resistance of the coil in the injector by putting the multimeter on the two pins on each injector and note the value. Anything <2 ohms or > 4 ohms needs more attention

Then with the ignition switch on and the injector connectors off measure the voltage at the harness pins. One should read 0 volts and the other close to battery voltage. This checks the wiring from the MP relay to the resistor pack to the injector. Note which of the two pins reads zero. If any connector has both pins measuring 0 there is a problem in the power side of the wiring for that injector. Got back and check the resistor pack. If none of the pins have power the MPI relay may not be turning on.

Next disconnect the middle connector on the ECU and with your multimeter on ohms again measure each of those pins to ground. You should read infinite resistance if they are not shorted to ground.

To check the wires for continuity between the injector and ECU reconnect the injector harnesses and at the ECU middle connector with it still disconnected from the ECU and the ignition switch on, measure pins 51, 52, 60, 61. Again they should all read close to battery voltage. You have now checked the circuit from the MPI relay to resistor pack to the injector to the ECU. If any of them don't have battery voltage on them there's a problem.

It's still possible that two or more wires are shorted together but it's unlikely. To check that, you would disconnect all but one injector connector and then check those 4 pins again. Only the matching injector pin should have voltage on it. Repeat for the other 3 injectors.

Steve

 

[TUI2I30]

Steve, thanks for your reply. I called the guys at Foreign Auto Computer, inc today. They serviced this ECU and told me it is still under warranty. So I sent it back to them at their request. They remembered the previous owner of my car and told me they would honer that warranty. As previously stated this ECU had the caps go bad on it, I don't think they fixed everything. They told me that they may just send me another ECU pending inspection of this one. They probably just want to make sure that I didn't break the warranty void label. I'm keeping my fingers crossed!

 

[steve]

I hope that works out for you.

Steve

 

[TUI2I30]

I hope that works out for you.

Steve

Thanks, I'll post back when I get the ECU back.

 

[oldman]

Thanks, I'll post back when I get the ECU back.

And if for some reason it didn't work out, steve would be the person to send your ecu to. In case if you don't already know, he's one of the best in the business. http://simon.chi.il.us/~steve/Auto/DSM/ECURepair.html

 

[TUI2I30]

perfect! Thanks guys!

 

[TUI2I30]

ECU took care of issues, I am now running on all 4 and I am not pissing fuel. WOOHOO. on to the next issue, new post. Thanks guys!

 

[oldman]

ECU took care of issues, I am now running on all 4 and I am not pissing fuel. WOOHOO. on to the next issue, new post. Thanks guys!

Finally... Congrates..