FIC injectors installed....is this normal...
Thread Starter
Instructor
Joined: Nov 2008
Posts: 107
Likes: 7
FIC injectors installed....is this normal...
got the injectors and installed in 30 mins. Car is a 92. Needless to say the car runs great with no more miss. One thing I noticed is a bit weird. First time I fired it, the idle was steady at 900 even when hot. After a bit of run time I let it sit and fired it again. This time it came down to 750 or so. Went for a drive and after 5 mins of driving it was back to 900. Let her sit for about 2 hours, fired it again and it settled at 750. Rock steady with no surging. But I do notice that as the car gets warmer and after it is driven, the idle does creep up. This sound normal? I will say that after reconnecting the battery I only drove it for 3 miles or so. I did let it idle for 15 mins as stated in the directions.
Max G’s
Joined: Nov 2008
Posts: 2,751
Likes: 79
From: Monroe OH
NCM Sinkhole Donor
got the injectors and installed in 30 mins. Car is a 92. Needless to say the car runs great with no more miss. One thing I noticed is a bit weird. First time I fired it, the idle was steady at 900 even when hot. After a bit of run time I let it sit and fired it again. This time it came down to 750 or so. Went for a drive and after 5 mins of driving it was back to 900. Let her sit for about 2 hours, fired it again and it settled at 750. Rock steady with no surging. But I do notice that as the car gets warmer and after it is driven, the idle does creep up. This sound normal? I will say that after reconnecting the battery I only drove it for 3 miles or so. I did let it idle for 15 mins as stated in the directions.
Drifting
Joined: May 2005
Posts: 1,336
Likes: 12
From: Chicago Executive Airport, formerly known as Palwaukee
No-IL Events Coordinator
St. Jude Donor '12-'13-'14-'15-'16-'17
Give Jon a call. He might be able to tell you what needs to be done.
His injectors are designed to be a complete "Plug & play" experience.
You might possibly have another issue with one of the many sensors on your LT1 engine.
His injectors are designed to be a complete "Plug & play" experience.
You might possibly have another issue with one of the many sensors on your LT1 engine.
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
Probably have an air leak in the plenum/runner assy gaskets. You say you did the work in 30 minutes? That's a bit too fast to be good, clean work. Even on a LT.
You have air leaks. You will also have fuel leaks from rail o-rings soon. You can get air leaks in the inj seats if the inj was not "set" properly and the new o-rings were not lubed with vasoline.
You also have to drive the car to establish a BLM that will help the ECM establish a pattern for the "tune" that is programmed. The BLM helps to anticipate so the ECM reacts faster instead of waiting...OBD-I ECMs of the 80s had as much power as a cheap calculator today. "pong" of the automotive electronics world...
Each time you d/c the battery you clear the BLM and the ECM has to re-establish a new set. Memories...
You have air leaks. You will also have fuel leaks from rail o-rings soon. You can get air leaks in the inj seats if the inj was not "set" properly and the new o-rings were not lubed with vasoline.
You also have to drive the car to establish a BLM that will help the ECM establish a pattern for the "tune" that is programmed. The BLM helps to anticipate so the ECM reacts faster instead of waiting...OBD-I ECMs of the 80s had as much power as a cheap calculator today. "pong" of the automotive electronics world...
Each time you d/c the battery you clear the BLM and the ECM has to re-establish a new set. Memories...
Last edited by leesvet; Jan 18, 2013 at 11:14 PM.
Race Director
Joined: Jan 2005
Posts: 10,641
Likes: 13
From: Slidell Louisiana
Probably have an air leak in the plenum/runner assy gaskets. You say you did the work in 30 minutes? That's a bit too fast to be good, clean work. Even on a LT.
You have air leaks. You will also have fuel leaks from rail o-rings soon. You can get air leaks in the inj seats if the inj was not "set" properly and the new o-rings were not lubed with vasoline.
You also have to drive the car to establish a BLM that will help the ECM establish a pattern for the "tune" that is programmed. The BLM helps to anticipate so the ECM reacts faster instead of waiting...OBD-I ECMs of the 80s had as much power as a cheap calculator today. "pong" of the automotive electronics world...
Each time you d/c the battery you clear the BLM and the ECM has to re-establish a new set. Memories...
You have air leaks. You will also have fuel leaks from rail o-rings soon. You can get air leaks in the inj seats if the inj was not "set" properly and the new o-rings were not lubed with vasoline.
You also have to drive the car to establish a BLM that will help the ECM establish a pattern for the "tune" that is programmed. The BLM helps to anticipate so the ECM reacts faster instead of waiting...OBD-I ECMs of the 80s had as much power as a cheap calculator today. "pong" of the automotive electronics world...
Each time you d/c the battery you clear the BLM and the ECM has to re-establish a new set. Memories...
Concur with you on lubing the o rings will alleviate the possibility of tearing one on install. If the OP removed the battery during his install after some driving time the idle speed may even out. However, if it were mine I'd clean the TB and IAC ....
MIke
Thread Starter
Instructor
Joined: Nov 2008
Posts: 107
Likes: 7
Injectors and rail were treated with lube and set correctly. There were no leaks. When first started it idles excellent at 700-750 so I am confident there are no vac leaks. It is after it is driven that the idle creeps up. And again, it was only driven a few miles and has about 30 mins idle time on it so it may still correct itself once the ECM gets more drive time.
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
I keep forgetting that LTs are 1 piece and not 3 piece like L98s.
If you're sure there are no o-ring air leaks or others then it has to be related to the ECM being cleared of memory.
There is a min time for the ECM to read and store the new BLM patterns for lack of a better term...its a matter of seeing a brief example of how the car is running and storing that data so the program can react faster in the future...a little like cookies on the computer. Erase them and the computer has to search to load a page the hard way...if cookies are present thats a short cut to the same end result.
I forget what the min time was...it wasn't much. Something like 30 sec above ?? mph steady. I dunno...its been a while. Maybe it was 8 secs over 30 mph?
Whatever,. it was pretty easy to do.
If you're sure there are no o-ring air leaks or others then it has to be related to the ECM being cleared of memory.
There is a min time for the ECM to read and store the new BLM patterns for lack of a better term...its a matter of seeing a brief example of how the car is running and storing that data so the program can react faster in the future...a little like cookies on the computer. Erase them and the computer has to search to load a page the hard way...if cookies are present thats a short cut to the same end result.
I forget what the min time was...it wasn't much. Something like 30 sec above ?? mph steady. I dunno...its been a while. Maybe it was 8 secs over 30 mph?
Whatever,. it was pretty easy to do.
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Supporting Vendor
Joined: Mar 2008
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From: Cumming Ga
I would think the iac might be sticky.. the iac is a controlled vac leak, make sure the throttle blade shaft is smooth and the throttle cable is free and not sticky. make sure none of the vac hoses are loosely fitted. Its air for sure..
Cole
Cole
Race Director
Joined: Jan 2005
Posts: 10,641
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From: Slidell Louisiana
....and is the reason I posted the following yesterday "... However, if it were mine I'd clean the TB and IAC ...."
MIke