Wierd AFR, bad respons, fresh turbo build
04-04-2010, 02:54 PM
#1
Staging Lane
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Wierd AFR, bad respons, fresh turbo build Hi!
I have been trubbleshooting alot latley but im totally out of idees and i need to get the ride going so i can go to a tuner.
The engine is a LS1 with Ford green 42lbs injectors running hptuners and 60psi.
The guy i bought the engine from sa id that it maybe had a cam installed. I, offcourse did not run the engine before i started building turbo, ++
I have also cut the wiring alot to remove unecesarily equipment.
It has new spark plugs.
My problem is that my afr gauge shows 5-8 at idle and free revving, it got bad respons while revving compared to a stock LS1 and ive only seen the afr at 12-13 once for a short short time. Im not so used to ls1 so i can really hear that it runs poorly but my friend knows.. Compared to his its slow.
What ive tried so far:
-Compression tested it, shows 175psi on everyone (cheap tester)
-unplugged all sparkplugs one by one to check difference in RPM, Some cyl make the rpm change more than others but every cyl do change the RPM
-Unplugged all the sparkplugs, p/s -> All grey/white , d/s -> two grey/white, two black
-Unplugged the injector connections to see if there is a change. It is, but some (cylnr 3,5) do make the AFR leaner..
So, the engine is not tuned, ive done the mods for SD tune and change my IFR table.
Does anyone have any good inputs? Im quite novice at these engines and im really stuck at the moment.
Thanks in advance,
Sindre
I have been trubbleshooting alot latley but im totally out of idees and i need to get the ride going so i can go to a tuner.
The engine is a LS1 with Ford green 42lbs injectors running hptuners and 60psi.
The guy i bought the engine from sa id that it maybe had a cam installed. I, offcourse did not run the engine before i started building turbo, ++
I have also cut the wiring alot to remove unecesarily equipment.
It has new spark plugs.
My problem is that my afr gauge shows 5-8 at idle and free revving, it got bad respons while revving compared to a stock LS1 and ive only seen the afr at 12-13 once for a short short time. Im not so used to ls1 so i can really hear that it runs poorly but my friend knows.. Compared to his its slow.
What ive tried so far:
-Compression tested it, shows 175psi on everyone (cheap tester)
-unplugged all sparkplugs one by one to check difference in RPM, Some cyl make the rpm change more than others but every cyl do change the RPM
-Unplugged all the sparkplugs, p/s -> All grey/white , d/s -> two grey/white, two black
-Unplugged the injector connections to see if there is a change. It is, but some (cylnr 3,5) do make the AFR leaner..
So, the engine is not tuned, ive done the mods for SD tune and change my IFR table.
Does anyone have any good inputs? Im quite novice at these engines and im really stuck at the moment.
Thanks in advance,
Sindre
04-05-2010, 10:30 AM
#5
Idle afr should be 14.7 ideally at idle and part throttle . Can get by a bit richer but for sure can't be like 5 that would instantly stall out I would say and foul plugs like crazy. Yet sounds like only two are fouling.
At wot it should be like high 12s to 13.0 range for NA . Boost you usually run like 11.5 to 11.8 or so. Some guys do like to run 11 and some a bit richer yet but usually no need to go that rich.
For tuning of course you need to set the target afr and get timing down as well from stock. Also how much boost are you running give a bit more details on car,mods,etc.
You could have some other big issues depending on what was done to wiring??
Tuning if way whacked can definitely make a car run pig rich. If the injectors are way out to lunch. What tuning program are you using. Do you know how to post tune files if its hptuners?
Can you read off the injector constants. Do you have adjustable fuel reg or just stock intank one? Fuel pressure if adjustable is usually set at 58psi vacuum line off.
Are you sure they are 42s..are they all 42s do they all match in color?
That pig rich if accurate might also be from some other cause...maybe massive vacuum/boost leak? Plug wires burnt up,off..and set gap for boost to around .030 is good starting point..and colder plug like tr6 ix or tr6 in ngk line.
Too many unknowns here we need more details.Are you trying to run open loop or using narrowband 02 sensors still. Are they shot?
At wot it should be like high 12s to 13.0 range for NA . Boost you usually run like 11.5 to 11.8 or so. Some guys do like to run 11 and some a bit richer yet but usually no need to go that rich.
For tuning of course you need to set the target afr and get timing down as well from stock. Also how much boost are you running give a bit more details on car,mods,etc.
You could have some other big issues depending on what was done to wiring??
Tuning if way whacked can definitely make a car run pig rich. If the injectors are way out to lunch. What tuning program are you using. Do you know how to post tune files if its hptuners?
Can you read off the injector constants. Do you have adjustable fuel reg or just stock intank one? Fuel pressure if adjustable is usually set at 58psi vacuum line off.
Are you sure they are 42s..are they all 42s do they all match in color?
That pig rich if accurate might also be from some other cause...maybe massive vacuum/boost leak? Plug wires burnt up,off..and set gap for boost to around .030 is good starting point..and colder plug like tr6 ix or tr6 in ngk line.
Too many unknowns here we need more details.Are you trying to run open loop or using narrowband 02 sensors still. Are they shot?
