TPI Tuned Port Injection discussion and questions. LB9 and L98 tech, porting, tuning, and bolt-on aftermarket products.
Sponsored by:
Sponsored by:

L98 rough idle & hisitation

Thread Tools
 
Search this Thread
 
Old Mar 24, 2013 | 03:21 PM
  #1  
camping44's Avatar
Thread Starter
Junior Member
 
Joined: Mar 2013
Posts: 2
Likes: 0
Car: 1989 Formula
Engine: L98
Transmission: 700R4
L98 rough idle & hisitation

guys need your help:
1989 formula 350
N10 car with shorty headers 3" Flowmaster exhaust, and cold air K&N intake, and a hypertech chip street tunner.
there are some rear suspension upgrades as well, torsion arm, PH Bar, trailing arms.
I just got this car and it runs great but i do have 2 annoying issues / or maybe there not issue but normal.
1). at idle the car is annoyingly rough at 700 RPM shakes and shimmies, start to accelerate normally, and car runs smooth as glass.
2). WOT from a stop and there is a hesitation or bog down issue, about a 1-2 sec delay and the car launches, doesn't break the tires loose.

Car has had a recent tune up, going through poking around i see 2 of the injectors have been changed, car has 90K miles on it, also the guy i bought it from was maticulous i have all the reciepts and history over the past several years.

new to these FI, CC cars as i am an old school carburator guy, any help would be great, injectors, TPS, MAF?
Thanks
Reply
Old Mar 25, 2013 | 10:48 AM
  #2  
busterbrown's Avatar
Junior Member
 
Joined: May 2010
Posts: 34
Likes: 0
From: Lexington, KY
Car: 1992 formula firebird
Engine: 355 TPI
Transmission: currently a T-5, eventually a T-56
Axle/Gears: 3:42
Re: L98 rough idle & hisitation

Has it been this way since the tune up? Also, did they adjust the timing during the tune up? if so, you may need to adjust the base timing. For what its worth thats what it sounds like to me.
Reply
Old Mar 25, 2013 | 07:45 PM
  #3  
camping44's Avatar
Thread Starter
Junior Member
 
Joined: Mar 2013
Posts: 2
Likes: 0
Car: 1989 Formula
Engine: L98
Transmission: 700R4
Re: L98 rough idle & hisitation

i'm not sure since i got the car after their tune up, i haven't had it very long.
as a note i did take it our to a nice flat deserted road, and after i got done playing the car is idling alot smoother than before.
could it just have been clogged up?
as far as acceleration goes i'm not sure there's an issue there either, still seems to have a delay to it, but keeping the tires from spinning was much more difficult with the dedicated commitment to the floor board.
Thanks for your help
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
bamaboy0323
Tech / General Engine
25
Sep 3, 2015 06:07 AM
JHX
Tech / General Engine
4
Aug 29, 2015 02:30 PM
Bradsaundry
TPI
7
Aug 12, 2015 12:34 AM




All times are GMT -5. The time now is 10:56 PM.