Scan showed a misfire in cylinder #2.

Tiny
KNICKER26
  • 2007 PONTIAC G5
  • 123,000 MILES

I had the ECM scanned and the code was for a #2 cylinder misfire. I was told it could be the plugs, the injector, or the ignition coil. I suspect its the injector because it idles rough and city MPGs have dropped. Car seems ok on the highway. I'd like to change the injector myself. I need instructions on how to do it.

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Wednesday, December 28th, 2011 AT 4:03 AM

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Tiny
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I wouldnt just go replacing the injector without checking things first. Another thing that can cause the missfire is low engine compression and it could smooth out while on the highway. Have you inspected the plugs and wires yet?I would also do a compression test.

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Wednesday, December 28th, 2011 AT 4:33 AM
Tiny
KNICKER26
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I should have mentioned that plugs for all 4 cylinders were changed and the situation did not improve.

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Wednesday, December 28th, 2011 AT 3:19 PM
Tiny
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Why dont you check the compression of all the cylinders. Auto zone rents the compression to rule that out.

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Wednesday, December 28th, 2011 AT 8:26 PM
Tiny
KNICKER26
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Ok, say I am losing compression in cylinder 2. What are my options? I don't have the funds for a rebuild. The car has 125,000 miles. If I made it to 150,000 I would be happy.

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Friday, January 27th, 2012 AT 2:46 AM
Tiny
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What are the compression readings?If you have low compression its most likely caused by a valve issue not a ring issue.

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Friday, January 27th, 2012 AT 2:59 AM
Tiny
KNICKER26
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30PSI in cylinder #2. 100+ in 1, 3, 4. Car runs ok on hwy and speeds over 45mph. Idles rough. Idles at 1500RPM. Before it idled at less than 1000.

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Thursday, March 8th, 2012 AT 12:54 AM
Tiny
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30Psi compression in cylinder number 2 wouldbe what we would call a dead hole. Meaning there isnt enough compression for that cylinder to fire. You said the other cylinders were a 100 plus pounds do know the exact pressures?

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Thursday, March 8th, 2012 AT 1:16 AM
Tiny
KNICKER26
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No I don't I'm afraid. The mechanic told me 1, 3, 4 were at normal level. Someone told me that it was not uncommon for ecotecs to have this problem.

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Thursday, March 8th, 2012 AT 12:51 PM
Tiny
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I know the early ecotechs had issues with there timing chains tenisors. They are actually a pretty good engine I have see some valve issues here and there cause low compression like yours is doing.

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Thursday, March 8th, 2012 AT 4:41 PM
Tiny
KNICKER26
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I'm still driving the G5. It knocks like that is a valve or cam problem. The car runs rough in the city ok on the hwy. At idle or city driving you can smell gas. On the hwy there is no gas smell. I cannot afford to rebuild the engine, or any other major work. I need this car to run as long as possible. Is there anything I can do to minimize the gas smell?

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Saturday, June 9th, 2012 AT 3:12 AM
Tiny
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When you only have 30 psi on cylinder 2 that cylinder isnt firing so your going to smell gas. Untill you remove the head and address the compression issue not much you can do. There is no easy fix.

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Saturday, June 9th, 2012 AT 5:44 AM
Tiny
KNICKER26
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There was a hole in the "flextube" that attaches the first Cat convertor to the exh manifold. Would a leak in this short tube cause a loss of compression? The result would be no necessary back pressure.

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Thursday, August 2nd, 2012 AT 5:28 PM
Tiny
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Thats not going to stop your rings and valves from seating especially on just one cylinder.

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Thursday, August 2nd, 2012 AT 11:21 PM

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