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Re:Re:2011 Buick LaCrosse Engine Misfire on injectors 3,4 and 6
Good day all. I’m getting my but kick by this lacrosse. Here’s my situation. The car has a misfire on injectors 3,4 and 6. It’s powered and ground by the ECM. All of the injectors are good. I put a Noyd light on them and that’s how I know the ones that aren’t working, in doing my testing I now know that the injectors mentioned above are not getting power from the ECM. I did a continuity test on the wiring and they are all good. My question is how do I test the computer to see if it’s the problem? I am kinda confuse with the resistance testing but I’m watching and reading more in that area, any direction right now is appreciated. Thanks. I’m wondering if the driver in the ECM is gone but wanna be sure because the ECM is very costly. Thanks everyone
Good day. I’m getting my but kick by this lacrosse. Here’s my situation. The car has a misfire on injectors 3,4 and 6. It’s powered and ground by the pcm. All of the injectors are good. I put a Noyd light on it and that’s how I know they aren’t working, in doing my testing I now know that the injectors mentioned above are not getting power from the ECM. I did a continuity test on the wiring and they are all good. My question is how do I test the computer to see if it’s the problem? I am kinda confuse with the resistance testing but I’m watching and reading more in that area, please I know you guys are very busy, but any direction right now is appreciated. Thanks.
Last edit: 2 years 11 months ago by Chad. Reason: Post merged with original thread
The car is a Buick LaCrosse 3.6v. The situation is the car is throwing a 1255 code. The car is missing on cylinders 3,4 and 6, did a few checks and found out that the ECM is not supplying power to the injectors mentioned above. I’ve clean all the injectors, did a Resistance test on them and they seem fine. It looks like someone has switch out a few of the injectors, anyways please any help will be greatly appreciated. How can I test the.ECM to see if it the problem? Because after it’s the ECM that supplies both ground and power.
Last edit: 2 years 11 months ago by Chad. Reason: Post merged with original thread.
Like Ben noted, power is not directly supplied by the computer, but rather by a fuse. If the fuse has power as you say but the injectors do not, then there is an open circuit between the fuse and the injectors.
What is the definition of the trouble code you posted? I tried looking it up but found no p1255...
Actually we were both wrong in assuming it was all time power feed supplied by fuse.... diagram shows those 2 fuses supplying the pcm with power and a driver on power and ground? I'm not sure why maybe the inductive kickback of the gdi injector?any rate ill get pcm pin later to check for power at pcm I suspicion its the power supply circuit as that would affect a bank a pcm issue would likely be isolated to a single injector.
Thank you so much for your feedback. We had move it to the side for a while, but the problem was the ECM wasn’t firing the injectors or should I say” grounding” new ECM on the way so we’ll let everyone know how it go.
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