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2000-2005 Discuss your 2000-2005 Bonneville SE, SLE, and SSEi Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.

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Old 01-09-2009, 09:56 PM   #21
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Ok, all coil packs read .8 (.5-.7) on the primary and 9.12 -9.14 (5k-11k) on the seconday. Car is still throwing the P0300 (random missfire), HP tuners doesn't report a missfire on any cylinder, but shows the P0300. In park, you can rev the car to the rev limiter. It revs easily with no miss. I can ease it up to highway speeds, but if I try to push in into any boost more than about 2lbs, it misses and the SES light flashes at me. It has new plug wires and ngk tr55ixs in it. Needing some help here, not sure what else to do.


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Old 01-09-2009, 10:05 PM   #22
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Not sure if I asked you this before. But have you checked to make sure none of the plug wires are near the O2 sensor wire. If you get to close strange things can happen.
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Old 01-09-2009, 10:07 PM   #23
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Danthurs, I think I checked that. I am going to check it tomorrow. Could it be a crank sensor failure?


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Old 01-09-2009, 10:15 PM   #24
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That is a possibility. But check that wire first. Keep the plug wires as far form the O2 wire as you can.
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Old 01-09-2009, 10:16 PM   #25
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Any chance this could be a tank of bad gas? It started 3.8 gallons into this tank.


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Old 01-09-2009, 10:24 PM   #26
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Have you tried using some seafoam? 1/3 can in the vac line and the other 2/3 can in the fuel tank. I've seen this do wonders. If you got some bad gas that may clear it up by cleaning the injectors. Also, have you inspected your plugs? Check to see if any of them look different, black, fowled, etc.
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Old 01-09-2009, 11:52 PM   #27
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same thing happening on my 97. if you figure out the problem let me know. might save me some time. thanks
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Old 01-10-2009, 04:38 PM   #28
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problem solved i tested all 6 of the coils i had here are were about 5600 ohm in the secondary with a few up to 6100. all were at .8 on the primary except those with 6100 on the sec had .9 on the pri. so i changed those out and she now runs like a champ.

all the coils i used had .8 on the primary witch is .1 out of spec according to the post above so i plan on getting 3 new coils just to see if they make any difference.
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Old 01-10-2009, 04:44 PM   #29
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Glad you found it. It'* important that the coils are matched as close as possible. Just a little off on the primaries can have a big effect on the secondaries. When I installed my MSDs I noticed an improvment right away.
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Old 01-10-2009, 08:27 PM   #30
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all of the secondarys were in spec from what i found spec is 5-11k and all mine were about 5.6 to about 6.1 witch is spec. but 2 of them the primarys were just a little off from the rest. at first i did not think they were far enough off to make a difference but i figured while i was there i would chnage them anyways and i did and it fixed the prob.
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