I hear a slight popping when engine is under high load - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


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.

Reply
 
 
 
Thread Tools Search this Thread
Old 10-18-2007, 04:22 PM   #1
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Jun 2007
Location: Plymouth WI
Posts: 69
Thanks: 0
Thanked 0 Times in 0 Posts
lammers is on a distinguished road
Default I hear a slight popping when engine is under high load

i recently installed a 3.5' mps, and ever since, at high boost have been getting a popping in my intake. it is blow back, but i don't know where to start to try and fix it. i am hopeing i am not floating valves, but since it only started after i installed the smaller pulley, i don't think thats what it is. any help/ suggestions would be helpful.
lammers is offline   Reply With Quote
Old 10-19-2007, 08:02 AM   #2
Junior Member
 
Join Date: Apr 2006
Location: Purgatory
Posts: 0
Thanks: 0
Thanked 0 Times in 0 Posts
Bonneville92V688 is on a distinguished road
Default

Do you have a scantool? If not, I suggest you pick one up and check your numbers out. Any SES light on at all? And you are using 91 or higher, right?
Bonneville92V688 is offline   Reply With Quote
Old 10-19-2007, 09:07 AM   #3
DINOSAURUS BOOSTUS

Expert Gearhead
 
BillBoost37's Avatar
 
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Thanks: 0
Thanked 0 Times in 0 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 changed your plugs when you installed the pulley? Double check the wire routing.

A smaller supercharger pulley allows you to push more air into the motor. It does not seem logical that it would cause a backfire of any kind. Unless there was a pre-existing problem or something occurred during installation like a plug wire being crossed.
BillBoost37 is offline   Reply With Quote
Old 10-19-2007, 02:45 PM   #4
Senior Member
Posts like a Camaro
 
Join Date: Jan 2003
Location: Jenison, MI (Near Grand Rapids)
Posts: 1,070
Thanks: 0
Thanked 0 Times in 0 Posts
theJMFC is on a distinguished road
Default

Just to throw this out there: Could it be that the plug gap is too large for the added boost?
theJMFC is offline   Reply With Quote
Old 10-21-2007, 09:06 PM   #5
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Jun 2007
Location: Plymouth WI
Posts: 69
Thanks: 0
Thanked 0 Times in 0 Posts
lammers is on a distinguished road
Default

i installed the plugs about a month ago, so it'* not crossed wires. i was talking to my father, and he thinks it may actually be a lean pop. i still have the stock airbox on, and that may be restricting the airflow. not sure if that is it or not, but i am going to be getting a fwi hopefully soon to see if that takes care of the problem. as for the gapping issue, i have ngk iridium ix'* installed. i have them gapped for stock, so i am wondering if that gap being setup for stock boost is a problem, and what that would cause.

oh, and as for KR. It maxes at 2 at the top end of gears at WOT.
lammers is offline   Reply With Quote
Old 10-21-2007, 10:48 PM   #6
Senior Member
Certified Car Nut
 
Join Date: Mar 2003
Posts: 12,432
Thanks: 0
Thanked 0 Times in 0 Posts
J Wikoff is on a distinguished road
Default

For a short while I had Accel coil packs that would do that.
J Wikoff is offline   Reply With Quote
Old 10-22-2007, 09:19 AM   #7
DINOSAURUS BOOSTUS

Expert Gearhead
 
BillBoost37's Avatar
 
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Thanks: 0
Thanked 0 Times in 0 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

Ok..

Does it appear to run less than smooth? The stock intake is only a minor restriction that shoudl not cause this issue.

Remove the valve cover cap and try to duplicate the issue. Do you have a way to get the data scanned from the car to see if it'* running lean?
BillBoost37 is offline   Reply With Quote
Old 10-24-2007, 04:03 PM   #8
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Jun 2007
Location: Plymouth WI
Posts: 69
Thanks: 0
Thanked 0 Times in 0 Posts
lammers is on a distinguished road
Default

well 2 new developments/thoughts..... the first is my exhaust is extremely restricted, so probably a bad cat. The second thing is that i believe the stock gapping on my plugs may be causing the popping at high rpm. This is what i think is causing the problem, i will find out in a couple days when i replace the cat and regap the plugs. i will post if this fixed the issue or not.
lammers is offline   Reply With Quote
Old 10-24-2007, 06:27 PM   #9
DINOSAURUS BOOSTUS

Expert Gearhead
 
BillBoost37's Avatar
 
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Thanks: 0
Thanked 0 Times in 0 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

The stock gap isn't causing any issue except maybe a little predetonation and you aren't experiencing KR at shutdown.

Get that exhaust fixed. Most likely it'* the problem.
BillBoost37 is offline   Reply With Quote
Old 11-01-2007, 05:15 PM   #10
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Jun 2007
Location: Plymouth WI
Posts: 69
Thanks: 0
Thanked 0 Times in 0 Posts
lammers is on a distinguished road
Default

well, i replaced the cat, regapped the plugs, replaced o2'*, and put a cai on, and i still have the popping. the popping occurs under heavy load, in the middle of gears. on the top end of the gears the popping disappears.... later today i am installing a performance plug wire set, and an intense pcm to see if it helps any. I am not sure if it will help, but the intense pcm will make the car more fun. i also have been experiencing KR in first gear starts at 0 works up to 1, in second it is 0-1-2, then when it shifts into third it is 2-3 and i haven't held WOT too far into third, as i would have to drive over 100 to check this out.

please post any thoughts as to either issue of the popping or the KR
thanks in advance
Justin
lammers is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
2001 SSEi with slight surge under light load 68400fbird 2000-2005 0 12-21-2007 05:53 PM
Engine rattle under load james5275 1992-1999 5 12-04-2007 12:41 AM
Hear Ye, Hear Ye Village Idiots Mike Lounge 16 09-16-2006 08:17 PM
Update: figured out popping under load in all gears/misfire Brian95Blown 1992-1999 6 11-30-2004 07:02 PM
Car shudders in high gear under load - transmission? ssewannabe 1992-1999 43 05-09-2003 12:32 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 12:12 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.