lt1 timing
09-11-2005, 04:06 PM
#1
Supreme Member
Thread Starter
iTrader: (10)
Join Date: Sep 2002
Location: Ga.
Posts: 2,113
Likes: 0
Received 0 Likes
on
0 Posts
Car: sold
lt1 timing
i have a question what should the computer be running my timing at at idle? i was just waindering i seem not to have any of the line power. the timing at idle is like 20 degrees. and it seems to act like it has a cam but doesn't. i checked all the vaccum lines and they are good, anyone have any ideas? off the line it seems to have the same launch as my old 305. with 373 gears i figured it would boil the tires. i am running the 700 with the tci kit, i wouldnt think that would have anything to do with it. i was just curious on the timing and to see if anyone had any ideas, oh yeah and there is no knock retard detected.
09-12-2005, 11:03 AM
#4
Supreme Member
Join Date: May 2004
Location: Kingston, Tn
Posts: 2,924
Likes: 0
Received 1 Like
on
1 Post
Car: 1987 GTA
Engine: LT1
Transmission: T56
Axle/Gears: 9 bolt 3.70 posi
Sean I went back and looked at the old tune that was on the PCM when you sent it, and at 800RPM the timing was set at 21* advanced which is where the tune I put on the PCM was at as well.
09-12-2005, 01:15 PM
#5
Supreme Member
Thread Starter
iTrader: (10)
Join Date: Sep 2002
Location: Ga.
Posts: 2,113
Likes: 0
Received 0 Likes
on
0 Posts
Car: sold
i was just curious on the timing, i wasnt trying to imply anything. Im just trying to figure out what my botom end problem. i am just stabing in the dark, it seems to run great it just done excelerate l thought it should. but then again that could be the 700r4. i guess i will have to see what happend after i get the t56. thanks sean i plan on going to the track this friday i will haveto see what the improvements are from the last time. I finaly go all my exhaust clearance problems fixed. will have to see. hope its better then the 15.02 it ran last time. thats with the header giving it false knock and my alt took a sh*t. well i hope it is better.
09-12-2005, 08:18 PM
#6
Supreme Member
Join Date: May 2004
Location: Kingston, Tn
Posts: 2,924
Likes: 0
Received 1 Like
on
1 Post
Car: 1987 GTA
Engine: LT1
Transmission: T56
Axle/Gears: 9 bolt 3.70 posi
Np man, you had me wondering myself, the main reason I went and looked at it myself.
I pulled a stock M6 tune down and looked at it as well, and it was identical with 20* advanced at 800-850 and 40* at 5800
I pulled a stock M6 tune down and looked at it as well, and it was identical with 20* advanced at 800-850 and 40* at 5800
09-13-2005, 04:15 PM
#7
Supreme Member
Thread Starter
iTrader: (10)
Join Date: Sep 2002
Location: Ga.
Posts: 2,113
Likes: 0
Received 0 Likes
on
0 Posts
Car: sold
cool thanks for the repl. i think all my lowend problem is the 700r4. cant wait till i get the t56. was kina wondering does your engine run like crap till warmed up? what should the tps volts be
Last edited by ssean92; 09-13-2005 at 04:17 PM.
Trending Topics
09-13-2005, 04:49 PM
#8
Senior Member
Join Date: May 2003
Location: Houston-katy
Posts: 987
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1986 Irocz- Houstons Fastest Street
Engine: 408 LS1 w/ 2 stage
Transmission: Turbo 350
Axle/Gears: 3:73,3850 lbs , best of 9.92 @ 138
look, all you have to do is loosen the distributor bolt and adjust it till it idles good
p.s. i was being sarcastic. this sounds like a leak of vacuum in front of the intake that is making it idle like crap and will kill power with unmetered air
p.s. i was being sarcastic. this sounds like a leak of vacuum in front of the intake that is making it idle like crap and will kill power with unmetered air
09-13-2005, 05:06 PM
#9
Supreme Member
Thread Starter
iTrader: (10)
Join Date: Sep 2002
Location: Ga.
Posts: 2,113
Likes: 0
Received 0 Likes
on
0 Posts
Car: sold
i like a little sarcasume just like the next person, i was just trying to find my problem, i am still new to this fuel injection thing. would the tb upper plate cause this. the plastic piece on top?
Last edited by ssean92; 09-13-2005 at 06:00 PM.
09-15-2005, 11:39 AM
#12
Supreme Member
TPS is something like .5V - 4V (purely an educated guess, don't remember the exact numbers). There is some test procedure to test the IAC but I think its just measuring the resistance across 2 of the pins. check www.shbox.com for the test procedure, chilton's or something *might* have something but I doubt.
the only way a code would be thrown is if they were inoperative. The only real way to tell if TPS is at fault is to use a scantool and check the voltage a 0% and 100%.
*Edit: shbox does have the IAC test procedure, look at #'s 41 and 42 under the How To section.
the only way a code would be thrown is if they were inoperative. The only real way to tell if TPS is at fault is to use a scantool and check the voltage a 0% and 100%.
*Edit: shbox does have the IAC test procedure, look at #'s 41 and 42 under the How To section.
09-21-2005, 02:43 PM
#14
Member
Join Date: Jul 1999
Location: Kingfisher,Ok
Posts: 119
Likes: 0
Received 0 Likes
on
0 Posts
Car: 97 WS6 T/A
Engine: LT1 383
Transmission: 4L60E
Knock could cause it to accel down low poor as well.
Also my car at 800 rpm and a map of 40 has the spark advance at 25.5
Also my car at 800 rpm and a map of 40 has the spark advance at 25.5
09-21-2005, 03:45 PM
#15
Supreme Member
Thread Starter
iTrader: (10)
Join Date: Sep 2002
Location: Ga.
Posts: 2,113
Likes: 0
Received 0 Likes
on
0 Posts
Car: sold
im running the lt4 knock module, i have no knock retard at idle. i got this fixed, i moved the air filter farther away from the mass air sensor. it seemed to have fixed it some what.
09-21-2005, 04:55 PM
#16
Member
Join Date: Jul 1999
Location: Kingfisher,Ok
Posts: 119
Likes: 0
Received 0 Likes
on
0 Posts
Car: 97 WS6 T/A
Engine: LT1 383
Transmission: 4L60E
Originally posted by ssean92
im running the lt4 knock module, i have no knock retard at idle. i got this fixed, i moved the air filter farther away from the mass air sensor. it seemed to have fixed it some what.
im running the lt4 knock module, i have no knock retard at idle. i got this fixed, i moved the air filter farther away from the mass air sensor. it seemed to have fixed it some what.
09-26-2005, 08:38 AM
#17
Supreme Member
Thread Starter
iTrader: (10)
Join Date: Sep 2002
Location: Ga.
Posts: 2,113
Likes: 0
Received 0 Likes
on
0 Posts
Car: sold
it runs better but still acts like a cam. anyway to find out for sure if it is? with out tearing the engine apart? still looking for someone to tune my lt1. thanks sean
10-02-2005, 10:10 AM
#18
Member
Join Date: Aug 2005
Location: Lincolnton NC
Posts: 134
Likes: 0
Received 0 Likes
on
0 Posts
I don't know a lot about this but am in the process of putting an LT1 w/ 700R4 into an 86....just read a lot in a thread about the vss of the 700r4 vs the 4L60E and how it effects the ecm. Do you think this could be related to the lag you are seeing?
Here is the thread I was reading:
https://www.thirdgen.org/techbb2/sho...hreadid=310714
Here is the thread I was reading:
https://www.thirdgen.org/techbb2/sho...hreadid=310714
10-02-2005, 03:41 PM
#20
Member
Join Date: Aug 2005
Location: Lincolnton NC
Posts: 134
Likes: 0
Received 0 Likes
on
0 Posts
Cool, just read that thread today and thought I would pass it on. Do you still have that wierd idling or has moving the air filter really fixed everything? That is something I will have to remember in case I run into this....
One other thing I read, on shbox's website:
Too much EGR flow will dilute the a/f mixture and make the engine run rough or stall. Excess flow weakens combustion and may result in the following conditions:
Engine stops after cold start
Engine stops at idle after deceleration
Vehicle surges during cruise
Rough idle
Sounds like your description of acting like the car has a cam at idle even though it doesn't....anyway, I hope you found your bug and fixed it.
One other thing I read, on shbox's website:
Too much EGR flow will dilute the a/f mixture and make the engine run rough or stall. Excess flow weakens combustion and may result in the following conditions:
Engine stops after cold start
Engine stops at idle after deceleration
Vehicle surges during cruise
Rough idle
Sounds like your description of acting like the car has a cam at idle even though it doesn't....anyway, I hope you found your bug and fixed it.
10-02-2005, 05:22 PM
#21
Supreme Member
Thread Starter
iTrader: (10)
Join Date: Sep 2002
Location: Ga.
Posts: 2,113
Likes: 0
Received 0 Likes
on
0 Posts
Car: sold
actually it is better but not fixed. it doent do any of the things u described. anyway it doesnt have any of the smog stuff. so that cant be it. it isnt lopy like a cam it just has a rough idle.
10-02-2005, 06:52 PM
#23
Supreme Member
Join Date: May 2004
Location: Kingston, Tn
Posts: 2,924
Likes: 0
Received 1 Like
on
1 Post
Car: 1987 GTA
Engine: LT1
Transmission: T56
Axle/Gears: 9 bolt 3.70 posi
And Sean's has the exact same tune that was on my LT1 and mine ran like a champ so there's something else fishy going on, maybe a dirty MAF, but doubt it, could be a MAP or IAC valve possibly.
JDud, to be honest, and you can ask Firebat, or Sean about it, but save yourself some trouble, and get a 4L60E if you are running a '94 or newer setup, you will end up cheaper than buying a Dakota Digital box
JDud, to be honest, and you can ask Firebat, or Sean about it, but save yourself some trouble, and get a 4L60E if you are running a '94 or newer setup, you will end up cheaper than buying a Dakota Digital box
10-03-2005, 07:03 AM
#24
Supreme Member
Thread Starter
iTrader: (10)
Join Date: Sep 2002
Location: Ga.
Posts: 2,113
Likes: 0
Received 0 Likes
on
0 Posts
Car: sold
i was thinking that about the iac valve also. i did the ck from shoebox web site and it cked good. but that is the only sensor that hasnt been changed. should it run with the iac unpluged?
10-03-2005, 08:35 AM
#25
Supreme Member
I don't remember if the IAC returns to a specific position when you shut it down. If it does, doubtful it will idle at all, but it will run if you keep your foot in the gas.
Last edited by TexasLT1; 10-03-2005 at 08:39 AM.
10-03-2005, 08:38 AM
#26
Supreme Member
Thread Starter
iTrader: (10)
Join Date: Sep 2002
Location: Ga.
Posts: 2,113
Likes: 0
Received 0 Likes
on
0 Posts
Car: sold
could it cause the rough idle. my car is also leaning out the drivers side bank once it goes to closed loop. changed the o2 thought that might be it but no change. checked for pressure leak down after car was shut down nothing there. have heard that a injector must be leaking but how else can i ck for it?
10-03-2005, 08:40 AM
#27
Supreme Member
yeah it would probably run pretty crappy and stumble all over itself down low until you open the throttle up.
and injector could be leaking, but you'd have to take them out and send them to someone to get them cleaned/repaired.
and injector could be leaking, but you'd have to take them out and send them to someone to get them cleaned/repaired.
10-03-2005, 08:43 AM
#28
Supreme Member
Thread Starter
iTrader: (10)
Join Date: Sep 2002
Location: Ga.
Posts: 2,113
Likes: 0
Received 0 Likes
on
0 Posts
Car: sold
see thats the thing it doent do that. i just rocks alot shoot it might not be anything. it actually runns good going down the street. i got a 14.4 with a wore out tranny and no stall. so i guess i should just let it be. its just me being a perfectionest. thanks for the replies
10-20-2005, 11:44 AM
#29
Supreme Member
Thread Starter
iTrader: (10)
Join Date: Sep 2002
Location: Ga.
Posts: 2,113
Likes: 0
Received 0 Likes
on
0 Posts
Car: sold
i was sitting here and was wondering if my plugs might have anything to do with it? i am running no PLATINUM plugs as of now. could that be the idle problem. maybe i am making to much out of it but the rough idle is driving me crazy. anyone have an opinion?
10-20-2005, 02:16 PM
#32
Supreme Member
Join Date: May 2004
Location: Kingston, Tn
Posts: 2,924
Likes: 0
Received 1 Like
on
1 Post
Car: 1987 GTA
Engine: LT1
Transmission: T56
Axle/Gears: 9 bolt 3.70 posi
Get a set of the NGK TR6 plugs, everyone I've talked to locally runs that plug and it worked good for me.
07-13-2010, 06:53 PM
#33
Junior Member
Join Date: Feb 2010
Posts: 65
Likes: 0
Received 0 Likes
on
0 Posts
Re: lt1 timing
I would get some starting fluid or something similiar and spray around the injectors with it. Listen for the idle to rise and smooth out. You may have injectors that didnt seat properly. Its really easy to do and easily missed. You may have also in advertantly tore one of the o-rings or something. If you dont find it around the injectors continue to spray and suspect areas til you feel that there isnt a leak.
Thread
Thread Starter
Forum
Replies
Last Post
