NEED HELP changed plugs now it run bad!!!!!!!!!!!!!!!!
Thread Starter
Melting Slicks
Joined: Oct 2000
Posts: 2,156
Likes: 3
From: La Mesa CA
NEED HELP changed plugs now it run bad!!!!!!!!!!!!!!!!
Ok had a slight miss at highway speeds, not to bad but you could fill it now now then. So i took out the Boush platinums and put in the rapidfire #14s
gap is at .60 is that to much. Now it stumbles at 2000-3500 rpms bad and
the idle is jumping 600-1200 rpms did not do that befor i changed the plugs.
What do you think,would it be the plugs. It is a 94 and it dose have 85,000 miles on the plug wires. :confused: :confused:
gap is at .60 is that to much. Now it stumbles at 2000-3500 rpms bad and
the idle is jumping 600-1200 rpms did not do that befor i changed the plugs.
What do you think,would it be the plugs. It is a 94 and it dose have 85,000 miles on the plug wires. :confused: :confused:
Le Mans Master
Joined: Jan 2003
Posts: 8,596
Likes: 19
From: Portland Oregon
Re: NEED HELP changed plugs now it run bad!!!!!!!!!!!!!!!! (94TR)
I had thought that the plug gaps was around .045? For the standard OEM AC plugs. But from what you are describing it sounds more like an Opti spark problem. Does it idle rough as well? Any chance that you crossed a wire or to? If the plug wires are stock chances are there are numbers on each wire so you can ID it that way.
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Re: NEED HELP changed plugs now it run bad!!!!!!!!!!!!!!!! (94TR)
it could be the wires... also, the RF''s require a broader gap... so .060 sounds reasonable.
you may have a damaged wire (from pulling off and reinstalling.
could be the opti.
you may have a damaged wire (from pulling off and reinstalling.
could be the opti.
Safety Car
Joined: May 1999
Posts: 3,651
Likes: 5
From: Atlantis
Cruise-In I Veteran
Re: NEED HELP changed plugs now it run bad!!!!!!!!!!!!!!!! (94TR)
Could be a cracked insulator on one of the plugs you put in.
It's pretty easy to break them. Often, the result is what you describe.
Good luck with it.
It's pretty easy to break them. Often, the result is what you describe.
Good luck with it.
Safety Car
Joined: Feb 2002
Posts: 4,212
Likes: 10
From: Sun City West Az
Re: NEED HELP changed plugs now it run bad!!!!!!!!!!!!!!!! (VetNutJim)
If it was running without the symptoms that you have now, chances are you did something while doing the job. Ohm out your plug wires, recheck the plugs for proper gap and cracks and double check the firing order.
Instructor
Joined: Aug 2003
Posts: 172
Likes: 0
Re: NEED HELP changed plugs now it run bad!!!!!!!!!!!!!!!! (94TR)
My Two Cents..... In order of priority:
1. Check firing order and routeing of plug wires
2. Test drive (if error is found)
3. remove "new" plugs and install old
4. test
5. If improvement.... examine new plugs for damage ( often a dropped plug will have a closed gap) for ex. cracked insul., etc. Get the spec. and RE-Gap. Re-install. Test
Basically, check the easy, logical things first. Don't leap at "extreme possibilities. Good Luck
1. Check firing order and routeing of plug wires
2. Test drive (if error is found)
3. remove "new" plugs and install old
4. test
5. If improvement.... examine new plugs for damage ( often a dropped plug will have a closed gap) for ex. cracked insul., etc. Get the spec. and RE-Gap. Re-install. Test
Basically, check the easy, logical things first. Don't leap at "extreme possibilities. Good Luck
Drifting
Joined: Jul 2001
Posts: 1,897
Likes: 0
From: La Fontaine Indiana
Re: NEED HELP changed plugs now it run bad!!!!!!!!!!!!!!!! (bigjack)
If you read on the box it tells you that the rapid fires are gapped at 35 and DO NOT change them. I install my RF plugs just like they come out of the box never had a problem with them. When all else fails read the directions.
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Thread Starter
Melting Slicks
Joined: Oct 2000
Posts: 2,156
Likes: 3
From: La Mesa CA
Re: NEED HELP changed plugs now it run bad!!!!!!!!!!!!!!!! (94TR)
I checked the routeing of the wires OK. The side of the box said to set
gap at vehicle specification that is .50, on the AC Delco web site it said to set the gap at .60 so whitch is right, if you are running RF #14 in an LT1 what is
the gap set at. Dose not idle rough, but if you floor it and back off fast it will jump 600-1200 1 or 2 times then come back. :rolleyes:
[Modified by 94TR, 10:07 PM 9/20/2003]
gap at vehicle specification that is .50, on the AC Delco web site it said to set the gap at .60 so whitch is right, if you are running RF #14 in an LT1 what is
the gap set at. Dose not idle rough, but if you floor it and back off fast it will jump 600-1200 1 or 2 times then come back. :rolleyes:
[Modified by 94TR, 10:07 PM 9/20/2003]
Drifting
Joined: Jul 2001
Posts: 1,897
Likes: 0
From: La Fontaine Indiana
Re: NEED HELP changed plugs now it run bad!!!!!!!!!!!!!!!! (94TR)
I have a new box of Rapid Fire #9 that I have not installed yet and on the box in large bold print it say's [ GAP SET AT.035 DO NOT REGAP ]
The #9 is a colder plug for performance engines maybe some of the ones for stock engine are set at a different gap what was your gap before you changed them. The rapid fires that I have in my engine now have been flawless for past two years and I installed them at the pre-set gap .035
The #9 is a colder plug for performance engines maybe some of the ones for stock engine are set at a different gap what was your gap before you changed them. The rapid fires that I have in my engine now have been flawless for past two years and I installed them at the pre-set gap .035
Le Mans Master
Joined: Jul 2002
Posts: 5,818
Likes: 2
From: Alive and well in Burlington NC
Re: NEED HELP changed plugs now it run bad!!!!!!!!!!!!!!!! (black bart)
When all else fails read the directions.
Drifting
Joined: Jul 2001
Posts: 1,897
Likes: 0
From: La Fontaine Indiana
Re: NEED HELP changed plugs now it run bad!!!!!!!!!!!!!!!! (Steel Blue 91)
When all else fails read the directions.
Re-read the box for my RF #5s (91 L98) "Set gap per vehicle specification".
Re-read the box for my RF #5s (91 L98) "Set gap per vehicle specification".
Le Mans Master
Joined: Feb 2002
Posts: 7,858
Likes: 2
Re: NEED HELP changed plugs now it run bad!!!!!!!!!!!!!!!! (black bart)
Try 0.45 sound like with these plugs your opti-crap ignition is not going to work at wide gap. Also when you re gap check plug wire ends to make sure you didn't damage them when you changed the plugs.
I checked my rapidfire 14's out of the box and they had about an .055 gap. I felt better about gapping them down to .050 per OEM spec than gapping them up to .060. I just felt like (OEM spec) .050 was pretty wide already.
In his case, I think he has a couple plug wires crossed. Easy to do if you pull all the wire boots at once and then put plugs in, then go back and start putting on wires. I always go one plug at a time-- pull plug wire off, remove plug, install new plug, snap plug wire back on, move on to the next one. A little slower than the batch method but less open to human error.
P.S. If the plug wires have 80K on them, its time for new ones anyhow-- Taylor Spiro Pro's, MSD's, or Magnecore's :yesnod:
[Modified by Lone Ranger, 11:34 AM 9/21/2003]
