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2006 Scion tC Repair Question


Topics covered: Compression, Fuel pressure, Spark.
Mileage: 98,000 miles.

Asked on September 15, 2012

What can cause a fluxuating Idle (up and down about 500 rpm in park) and throw Misfire codes ( P0300-P0304) on a 2006 Scion tc?

2006 tc (the car is a manual shift) having idle problems worse if car is in gear at a stop. Idle will go up and dwn in park and shows codes P0300-P0304. Replaced plugs (which had the gap on two plugs closed other two where incorrect gap)cleaned TB, cleaned MAF, replace two vac hoses that had holes in them, checked injectors and still have same problem, car runs a little better but still has problem. Now when I started checking the COPS on the car I had the number 4 pulled out it had spark but did not slow down eng idle as other three had, as a matter of fact it caused the idle to smooth out an stop fluxuating after which when I put it back in the problem returned. So I switched Coils and exact same thing happened. Does any one have an Idea as to problem. Thanks
Avatar Asked by ellisone

Answer

Replied on September 15, 2012

check your fuelpressure it should be 44-50 psi at the rail. if it's not that can be causing the problem.

Tiny Answered by hmac300 (expert)
17,748 answers provided
Replied on September 15, 2012

Have the compression on #4 checked.

Tiny Answered by KHLow2008 (expert)
39,792 answers provided
Replied on September 16, 2012

Thanks will try both fuel pressure check an compression

Tiny Response from ellisone
9 questions asked