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RPM Fluctuations

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Old 04-15-2017, 07:26 AM
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Default RPM Fluctuations

I have a 1998 S10 Blazer in good co do too and have been having some problems.One when I am going down the road in overdrive you .ca feel hesitant when your driving you can see the tach jumping up and down which is showing a miss or something.Now I did have a code read out saying bad o2 sensor but need to go back out to have it re-read.There were several things.My dad was the second owner and now I own it.But I am thinking also maybe it needs plugs,wires etc.Any ideas???
 
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Old 04-15-2017, 07:58 AM
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*Moved to '2nd Gen Tech'*
 
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Old 04-15-2017, 09:13 AM
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If it is unknown how old the plugs, wires, cap, rotor are, then changing these are a good starting place. If an O2 sensor has failed, then engine is not going to run real well. Get the code read again to see which one it is, or replace both of them. (I think a '98 only has two?)
 
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Old 04-15-2017, 09:51 AM
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So you feel change plugs,wiresetc and the oxygen sensor?Now I know that was one code but I gotta see what the other one was and get back to you..
 
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Old 04-15-2017, 09:20 PM
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Yes I would change those items if it is complete unknown when or if they have ever been changed. Spark plugs last a long time these days but wires see so much heat they need changed more often. The rotor and cap are a close second to wires in needing to be changed with plugs the last.

If you are doing the work, be careful of removing the cap and especially putting the new one on. There are two small T10 screws that hold the cap on and these screw into tapped bosses on the distributor...THAT BREAK!! There is no fixing if the boss breaks off, only distributor replacement. Which is not costly, new all aluminum body dizzys are about $50 online. Better than the OEM plastic housings ones.

Checkout YouTube videos for plug changing hints.

BUT first, get all the codes and then post them.
 
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Old 04-16-2017, 05:32 AM
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Smile ReFuel Pump Buzzing

I have a 1998 S10 Blazer.Is it normal to really hear the fuel pump to make a loud buzzing noise?It has been doing this and I bought it off my dad ad do k ow it's been replaced beforeAndi keep getting a smell of gas fumes but see no leaks anywhere and it seems to come from the fuel filter side
 
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Old 04-16-2017, 05:41 AM
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I was in here yesterday asking what would cause blazer running in overdrive to hesitate and the Rach jumping up and down which is showing a miss of some sort.SHOULD the mad sensor be cleaned and new plugs and wires put in?I know my gas mileage hasn't been the best and could be better and need to get this fixed before I start pulling my pop up.Would appreciate help.
 
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Old 04-16-2017, 05:44 AM
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Thanks for the input I just hope this helps.I have no idea when the plugs or wires and that were changed by my dad who owned it.Thanks
 
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Old 04-16-2017, 09:41 AM
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*I have combined your threads into one so members can see the issues in one place and aid in providing help.*
 
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Old 04-17-2017, 05:26 PM
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Afternoon,
I have probably the same issue. I have done a number of things and while each upgrade seemed to improve things, it has not corrected the issue I've been chasing. A few things I haven't replaced yet... plug wires, ignition module, a complete new distributor, (i did do the cap and rotor), also I haven't done the O2 sensors.
If you happen to find the solution, I would greatly appreciate it if you'd let me know.
Good luck!
Later
 


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