2005 v70 T5-check engine light

Jeffn · Post by **Jeffn** » 31 May 2011, 11:23

DTC code p0300, p0303, and p0305. Repair shop replaced spark plugs and coil so far, but the light came back on after 2 weeks. Can anyone suggest what could be a problem?

Post by **jimmy57** » 31 May 2011, 11:44

You have to see what code is in there now. Could be back for a different reason.
Did the coils and plugs fix the misfire?\Is it still missing?

Jeffn · Post by **Jeffn** » 31 May 2011, 18:00

Thanks for responding.

The cylinder misfiring is unnoticeable while driving. No rough idling, or noticeable jerking while driving. The same DTC codes appeared first at about 46,000 miles. At that time the dealer’s mechanic did not know exactly what caused the misfiring and thought that is was anomaly. He suggested we wait for a reoccurrence. This problem did not reoccur for over a year.

At 60,000 miles, the check engine light came back on with the same codes. This is when we replaced the #5 cylinder coil and spark plugs (they were due for replacement at 60,000 miles anyway).

Two weeks later - 400 miles later, check engine light came on again with code P0300 (misfire, at least one cylinder) and P0305 (Misfire cylinder 5). It seems to come on more consistently, but no definitive solution by mechanic. Wait for reoccurrence. So this is where we stand right now. Any thoughts?

BobbyC · Post by **BobbyC** » 03 Jun 2011, 23:18

Change the plug, but not the coil, and see if the fault re-curs. Note the condition of the plug for deposits or whitish appearance if it was running too hot.

Swap the #5 coil with #4 and see if the misfire follows the coil, or stays in the #5 position.

Jeffn · Post by **Jeffn** » 12 Jun 2011, 15:35

Thanks, I'll try that.

I've driven the car for over 300 miles since, and no reoccurrence.