1992-1999 Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's and Buick Lesabres Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.

Misfires over 50?

Thread Tools
 
Search this Thread
 
Old 06-07-2007, 09:36 AM
  #1  
Senior Member
Posts like a Turbo
Thread Starter
 
J. Pierpont Finch's Avatar
 
Join Date: Oct 2006
Location: Kansas City, MO
Posts: 319
Likes: 0
Received 0 Likes on 0 Posts
J. Pierpont Finch is on a distinguished road
Default Misfires over 50?

Yea! A new problem.

At highway speed, the car 'feels' like it'* misfiring (I don't know for a fact that it is misfiring). I don't know how to describe it exactly, so I'll offer an analogy. Have you ever been walking down the sidewalk, and the next block of concrete is an inch higher than the last, and walking along normally your right foot hits it and half of you stops and the other half keeps going? That'* what it feels like.

I guess I'm saying I don't have the first clue whats happening, just feels like the motor is hiccuping.

Seems to only happen after it'* warmed up, at highway speed (between 50 and 70), and does it wether the AC is on or off. And it'* very rhythmic, about every 2 seconds, perhaps a bit less. But VERY noticeable.

I'm gonna run up to Autozone and have a scan run, but thought I'd throw this out in the meantime for consideration.

The only thing I've tried so far is to pour a bottle of fuel system cleaner in it.

Thanks -

Matt
Old 06-07-2007, 10:24 AM
  #2  
DINOSAURUS BOOSTUS

Expert Gearhead
 
BillBoost37's Avatar
 
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Likes: 0
Received 8 Likes on 8 Posts
BillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of light
Default

Well.. we might consider the wires and plugs.

I'm assuming when you did the motor, the old plugs and wires were reused from the two previous motors or .. the same wires that came with this motor were left on it.

That'll be a good starting point.
Old 06-07-2007, 10:49 AM
  #3  
Senior Member
Posts like a Turbo
Thread Starter
 
J. Pierpont Finch's Avatar
 
Join Date: Oct 2006
Location: Kansas City, MO
Posts: 319
Likes: 0
Received 0 Likes on 0 Posts
J. Pierpont Finch is on a distinguished road
Default

Thanks Bill - I just got back from 3 places to have a diagnostic run, 2 didn't have the right kind of tester, the third said if the check engine light isn't on, there won't be anything to read anyway. (It'* not on).

So I'm with you, because he did use the old plugs and wires. Also I take back the bit about only at highway speed, it does it all the time, just much less noticeable at lower speeds.

Since it only seems to happen after it gets warm, I'm going to check the coil resistance values and see if they are in spec, then it'* probably off for a new set of wires.... event of that'* not the problem, needs 'em anyway.

Thanks again

Matt
Old 06-07-2007, 11:15 AM
  #4  
DINOSAURUS BOOSTUS

Expert Gearhead
 
BillBoost37's Avatar
 
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Likes: 0
Received 8 Likes on 8 Posts
BillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of light
Default

Toss some fresh plugs in while you are doing the wires. Most likely .. you'll find a bad looking plug(*) when you swap them.

Thinking back to your description of the issue is a chuggle which is usually igntion related and felt once TCC lockup occurs. Searching on chuggle..you will find many references to it and typically it is ignition/tune up related.
Old 06-07-2007, 11:31 AM
  #5  
Senior Member
Posts like a Turbo
Thread Starter
 
J. Pierpont Finch's Avatar
 
Join Date: Oct 2006
Location: Kansas City, MO
Posts: 319
Likes: 0
Received 0 Likes on 0 Posts
J. Pierpont Finch is on a distinguished road
Default

Cool....

Here'* the reading from the coil packs:

CYL --- PRI --- SEC
3/6 --- .8 --- 6.24
2/5 --- .8 --- 6.01
1/4 --- .8 --- 6.00

These all seem to be well within tolerance, and they are still fairly warm from my trip, so I'm ruling out the coil packs for now. Up to get some plugs and wires, will let ya know what happens. If nothing changes, then I'll take it in for a tuneup.

Thanks
Matt
Old 06-07-2007, 12:08 PM
  #6  
Senior Member
Posts like a Turbo
Thread Starter
 
J. Pierpont Finch's Avatar
 
Join Date: Oct 2006
Location: Kansas City, MO
Posts: 319
Likes: 0
Received 0 Likes on 0 Posts
J. Pierpont Finch is on a distinguished road
Default

Well, here'* more proof that I'm a complete moron:

Checked the back row of plugs..... went to pull on the boot, and.....it came right off. I don't mean it 'popped' off, I mean.... it wasn't even connected. I guess it was close enough for the spark to jump most of the time, or at least occasionally. Plugged it in, took her for a test drive. Problem still exists, but to a MUCH lesser extent. I'm guessing all that arcing burnt up the inside of the plug wire.

So here'* a tip for Matt: Hey idiot, physically check things out before you post.
Old 06-07-2007, 12:15 PM
  #7  
DINOSAURUS BOOSTUS

Expert Gearhead
 
BillBoost37's Avatar
 
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Likes: 0
Received 8 Likes on 8 Posts
BillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of light
Default

Matt...don't be so hard on yourself.

You didn't put the plugs on right? Asking/searching first..will give you others insight as to the usual causes so you don't waste time looking at the things that don't cause the issue.
Old 06-07-2007, 12:33 PM
  #8  
Senior Member
Posts like a Turbo
Thread Starter
 
J. Pierpont Finch's Avatar
 
Join Date: Oct 2006
Location: Kansas City, MO
Posts: 319
Likes: 0
Received 0 Likes on 0 Posts
J. Pierpont Finch is on a distinguished road
Default

Thanks Bill !
Old 06-07-2007, 03:04 PM
  #9  
DINOSAURUS BOOSTUS

Expert Gearhead
 
BillBoost37's Avatar
 
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Likes: 0
Received 8 Likes on 8 Posts
BillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of light
Default

You want me to make you feel bad because you only tested 1/2 the coils? lol

When testing coils..build the confidence of your online buddy by not telling him..that to truely test..you must test the primaries also..that requires removing the coils. Always start with plugs and wires though.
Old 06-07-2007, 07:53 PM
  #10  
Senior Member
Posts like a Turbo
Thread Starter
 
J. Pierpont Finch's Avatar
 
Join Date: Oct 2006
Location: Kansas City, MO
Posts: 319
Likes: 0
Received 0 Likes on 0 Posts
J. Pierpont Finch is on a distinguished road
Default

but... but..... I tested sec & pri.... It'* in the table I posted above :?:
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
jllracer55
1992-1999
0
10-07-2008 11:41 AM
trigga_b
1992-1999
11
03-28-2007 11:50 AM
GM-Maine
2000-2005
8
03-18-2007 10:59 AM
Daron97SSE
1992-1999
6
03-13-2007 04:39 PM
impy
2000-2005
20
10-27-2006 09:00 PM



Quick Reply: Misfires over 50?



All times are GMT -4. The time now is 07:17 PM.