Need some help please. No pulse signal at the injectors when cranking. Car will start if carb cleaner applied. All ECM grounds rung out. Power at injectors with key on. Injectors bench tested and working. All engine sensors connected.
How to find out - Turn the key to on. Does the PCM run the fuel pump relay for two seconds and then drop off? It should. If not check for power to the PCM. Both switched and unswitched.
Q2 Is the PCM getting ignition pulses?
How to find out - AFTER passing the above, just bump the starter and see if the fuel pump relay comes on for two seconds again and then turns off again. It should. If not then look for why the PCM isn't getting ignition pulses. Note - If you crank the engine and oil pressure is built up, the oil pressure sender can also turn on the fuel pump. This is why you must only bump the starter for this test to be accurate.
Q3 Do you have an OBD2 scan tool/cable?
[This message has been edited by phonedawgz (edited 06-20-2013).]
So watch with the scan tool. See if it hooks up (PCM working). See if it shows the engine rotating during cranking. Finally make sure it shows the throttle working properly and closed during cranking.
Ended up being pin c1 20 Unswitched. The fuse was blown. Changed and it fired right up. Must had been blown prior to install and I did not notice it. Getting a P0300 and P0134. That's a new 02 sensor so ill ring out the wires and if good change it out. Thinking the miss fires are being caused because of the 02 problem. Thanks for the help!!!
A P0300 misfire code being present indicates misfires have been detected. Misfires can cause O2 sensor codes to set including the P0134 HO2S insufficient activity Sensor 1 code.
I would fix whatever is causing the P0300 code to set before worrying too much about the P0134 O2 sensor code. Whatever is causing the misfires could also be causing the O2 sensor code to set as well.
-ryan
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[This message has been edited by Darth Fiero (edited 06-24-2013).]
Ok finally had time to work on the car again. Got the miss-fire problem solved but still have the p0134 Looking at the wire colors on the harness connector and comparing to the 02 sensor connector they do not match? A & B do but C & D do not. C on the harness is blk and on the 02 it's brn D on the harness is pnk and on the 02 it's brn When I got the code I also noticed there was no voltage to the 02. Could C & D be switched or is it just the wrong 02 all together? I going to check the harness to insure all wires ring out correctly right now but any insight would be appreciated. Thanks
All the wires rung out correctly so I'm back to the 02 and the wire color difference. I had a second 02 off another exact engine and it made the engine run poorly as well. .
C & D are the O2's heater circuit. Polarity doesn't matter for a simple resistive heating unit. That is why the O2 manufacturer put two brown wires that run to the heater circuit. It doesn't matter which of the browns connects to the pink, just as long as the other connects to the black.
It is fairy normal for O2 sensors to have the same color for the wires that run to the heating element.
