doomviillain Posted November 3, 2014 Report Share Posted November 3, 2014 (edited) My AFR's like to jump around during idle and while driving, drives ok but I haven't been stomping on it, just around town cruising. Injectors are Fuel Injector Clinic 650cc/1150cc. are these afr's normal for TBI? I will record a cruising video soon. Edited November 3, 2014 by doomviillain Link to comment Share on other sites More sharing options...
markhansenconquest Posted November 3, 2014 Report Share Posted November 3, 2014 u have the wrong cc injectors u need 650 950 for stock aftermarket 87-89 stock oem have diffrent spray pattern....I was told after market run ruff because they make u have a wet manifold...so its hard it make it idle right.... Link to comment Share on other sites More sharing options...
Fuze Posted November 3, 2014 Report Share Posted November 3, 2014 ^^^True, the primary is too small and is also the only injector working at idle. Stock is 650 for the primary and about 800-900 for the secondary, so with that setup you must have either a MAF translator or a Super AFC to control the fuel mixture? If not, you'll run into problems especially when the car turns on the secondary at around 3500. Also, are you using a wideband AF monitor or something like the Autometer one that taps into the stock O2 sensor? A wideband won't bounce around so much but the other kind tend to appear to bounce back and forth wildly at idle and cruise and that's normal for them when the car is running right. Link to comment Share on other sites More sharing options...
scott87star Posted November 3, 2014 Report Share Posted November 3, 2014 Too lean, they like 13 AFR at idle. You need a way to alter fuel. Link to comment Share on other sites More sharing options...
Fuze Posted November 3, 2014 Report Share Posted November 3, 2014 OK watched the video (errrr shoulda done that b4) and yeah you are too lean at idle, probably because that primary injector is too small. You can either:A: replace that injector with a 650B: increase the fuel pressure with an adjustable regulator, but that will probably cause you to run too rich when that giant secondary comes onC: Dial the fuel up at idle and tune it for different rpm points with a Super AFC or MAF translator or similar fuel controller. The easiest way is to get a regular sized primary. Link to comment Share on other sites More sharing options...
doomviillain Posted November 3, 2014 Author Report Share Posted November 3, 2014 (edited) u have the wrong cc injectors u need 650 950 for stock aftermarket 87-89 stock oem have diffrent spray pattern....I was told after market run ruff because they make u have a wet manifold...so its hard it make it idle right.... sorry, small typo. The primary is 650cc ^^^True, the primary is too small and is also the only injector working at idle. Stock is 650 for the primary and about 800-900 for the secondary, so with that setup you must have either a MAF translator or a Super AFC to control the fuel mixture? If not, you'll run into problems especially when the car turns on the secondary at around 3500. Also, are you using a wideband AF monitor or something like the Autometer one that taps into the stock O2 sensor? A wideband won't bounce around so much but the other kind tend to appear to bounce back and forth wildly at idle and cruise and that's normal for them when the car is running right. Typo, fixed in the original post. Its a 650cc. I'm using an AEM uego wideband and its not tapped into the o2 sensor. The o2 sensor is on the downpipe behind the turbo while the wideband o2 is further down about 5 inches infront of the cat. I do have an apexi SAFCII, I tried altering fuel but it seems to run rougher no matter where I set it, so I stopped messing around with it and unplugged it and let it run on stock fuel maps, it idled and ran much better that way. Too lean, they like 13 AFR at idle. You need a way to alter fuel.You can either:A: replace that injector with a 650 B: increase the fuel pressure with an adjustable regulator, but that will probably cause you to run too rich when that giant secondary comes onC: Dial the fuel up at idle and tune it for different rpm points with a Super AFC or MAF translator or similar fuel controller. I dont have an adjustable FPR, ill try that next. As for altering fuel, I have the controller to do so, but as I said before, I alter the fuel at idle to make it run a bit richer at idle to get the AFRs at 13-15 but it bounces around and runs a bit rough, and even a few misfires. Oddly, when it misfires it bounces to full lean.... Edited November 3, 2014 by doomviillain Link to comment Share on other sites More sharing options...
scott87star Posted November 3, 2014 Report Share Posted November 3, 2014 Misfires always show up as lean on a wideband, there is a whole cylinder full of unused oxygen passing across the sensor. I also question whether the numbers are accurate, most times the G54b HATES any AFR over 15 and your idle at 16 seems OK (not great, but OK). So you either have an unusual motor or the wide band isn't reading correctly. Link to comment Share on other sites More sharing options...
TexasQuest Posted November 4, 2014 Report Share Posted November 4, 2014 You might have a faulty sensor or gauge. Link to comment Share on other sites More sharing options...
tsi_tom Posted November 4, 2014 Report Share Posted November 4, 2014 Just wondering why you don't have oil pressure. Link to comment Share on other sites More sharing options...
StarquestRescue Posted November 4, 2014 Report Share Posted November 4, 2014 Turn the base pressure up to about 45, you will need the safc2 to lean the car out under boost. Link to comment Share on other sites More sharing options...
Fuze Posted November 4, 2014 Report Share Posted November 4, 2014 ^^^^Yep. If you have the Delphi injectors then yeah they like higher pressure.. I run almost 50 psi for mine and it tend to smooth things out a little. Link to comment Share on other sites More sharing options...
doomviillain Posted November 4, 2014 Author Report Share Posted November 4, 2014 (edited) Fuel Injector clinic didn't tell me which kind they were, I just wanted a pair that would work with my car, anyhow, I will buy an adjustable FPR and report back with results but that would require modifying the fuel rail. Were there any bolt on fuel pressure regulators for this car? edit: forget if its bolt on or not (although this would make it much easier), which brand FPR works best? Just wondering why you don't have oil pressure. That gauge doesn't work, my car is still a work in progress... Edited November 4, 2014 by doomviillain Link to comment Share on other sites More sharing options...
markhansenconquest Posted November 4, 2014 Report Share Posted November 4, 2014 trilogy turbos make a bolt on regulator....look on e bay..Steven.... Link to comment Share on other sites More sharing options...
Fuze Posted November 4, 2014 Report Share Posted November 4, 2014 Any standard adjustable FPR will do the job, it just taps into the return line, there's no modification to the fuel rail needed. You just plug the vac line that goes to the stock reg into the new reg. Link to comment Share on other sites More sharing options...
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