# new member gen 2 2017 LT\RS 1.4 turbo\ autotrans....



## Butler00 (Jul 9, 2020)

any thoughts on the misfiring of cylinder 1 and low boosts this is second time this has happened. first time four new pistons codes were P0300-engine misfiring detected - sps program code11yn27493941 4066890 11.50 request 0.7 OLH for diagnosis of engine misfire (compression testing and leak down testing) verify owner concerns. they found misfire in Cly 1 they carry out a bulletin search. per bulletin 18-na-171 removed all spark plugs and ran compression test he found 140, 180, 180, 182psi in the cylinders. carry out leak down test on cylinder 1 and found more than 70% leak down into the engine crankcase. Carry out engine breakdown to inspect the cylinders walls for damage. no damage found. replace pistons as directed by doc id 5323672. replace all needed gaskets, seals and bolts as directed in the repair procedure, re-assemble vacuum fill the cooling system, clear fault codes, carry out crankshaft variation re-learn, ecm update as directed, road test. during road-test the vehicle misfire under medium throttle on cylinder 1. carry out ignition diagnosis and found the #1 spark plug to be failed. replace all spark plugs and road test for 15 mile and it passed

that was 13september2019 .. so that being 2 1\2 years and the same thing ids going on but im not no mechanic but i started at the spark plugs pull test and the number 1 didn't change so my survey says that replace plug and coil $84 versus dealer $260 just to diagnosis it sorry


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## Blasirl (Mar 31, 2015)

Butler00 said:


> any thoughts on the misfiring of cylinder 1 and low boosts this is second time this has happened. first time four new pistons codes were P0300-engine misfiring detected - sps program code11yn27493941 4066890 11.50 request 0.7 OLH for diagnosis of engine misfire (compression testing and leak down testing) verify owner concerns. they found misfire in Cly 1 they carry out a bulletin search. per bulletin 18-na-171 removed all spark plugs and ran compression test he found 140, 180, 180, 182psi in the cylinders. carry out leak down test on cylinder 1 and found more than 70% leak down into the engine crankcase. Carry out engine breakdown to inspect the cylinders walls for damage. no damage found. replace pistons as directed by doc id 5323672. replace all needed gaskets, seals and bolts as directed in the repair procedure, re-assemble vacuum fill the cooling system, clear fault codes, carry out crankshaft variation re-learn, ecm update as directed, road test. during road-test the vehicle misfire under medium throttle on cylinder 1. carry out ignition diagnosis and found the #1 spark plug to be failed. replace all spark plugs and road test for 15 mile and it passed
> 
> that was 13september2019 .. so that being 2 1\2 years and the same thing ids going on but im not no mechanic but i started at the spark plugs pull test and the number 1 didn't change so my survey says that replace plug and coil $84 versus dealer $260 just to diagnosis it sorry


Welcome Aboard!

You posted this in the introduction forum, I am going to put this in the appropriate subform. You will get more answers there.

Don't forget to go back and introduce yourself and your Cruze here.


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