Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
Hi my name is ***** ***** I will be happy to assist with this today.In some cases I may need more info to assist better.I apologize for any delay.
Can you tell me the year,make and model as well as engine size here?
Has anything been checked/tested or replaced for this fault here?
Let me know so we can continue,thanks Pete.
Has anything been checked,tested or replaced to try and locate or repair this fault here at all?
I dont see any bulletins or common faults on this here.It is possible the crank sensor is the cause here but this engine uses a set value for engine rpm any time the crank sensor signal is lost.The only issue that I have seen to cause this after an engine swap is incorrect wiring or wiring that was not wired properly or connected when the engine was installed.
I have seen loose or damaged grounds cause this fault here.Make sure all grounds are connected to the engine,all fuse panel and ignition wiring is connected and that the computer connections are all o.k. with no damaged or broken wiring.
If you havent checked for fault codes this should be done as well to see if any codes are set related to this fault here as this will help diagnose and locate the issue.
But usually it is a wire that is left disconnected that can cause this here.
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If the computer was replaced as well it will need programmed by a GM dealer.In some cases a computer will lose its programming and needs reprogrammed for similar issues like this here.See my post above as well.
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This can cause this fault here.If the harness is different it may be wired slightly different then your vehicle is wired.You might try and swap over the engine harness if you can and see if this resolves the fault here.I have seen where this engine is made for different emissions and in some cases different years and the harness can be different then on your model and had to swap over the harness to get the vehicle to start and run.
Are the wire colors different and is there any plugs that are not being used in this harness that your other harness doesnt have?
Happy New Years to you as well.
Have you checked fault codes at all using a scan tool that will plug in and communicate with all computers to see what codes are set with this issue here?
O.k.,let me know what codes are set?
Also clear out the codes then try and start and see what codes come back again and let me know.