well for some reason the car was running great and then ended up having surging issues @ idle and overall drivability was @!#$.
i changed the primary 02 sensor and no more surging or any other issues.
now when i first ended up getting the car out it was boosting great and now what seems like an overnight change as soon as it sees ANY boost air fuel drops to 9:1 for no reason and cant figure out WTF. fuel rail pressure was @ 58si and on advise from ryan and trying to isolate the issue i dropped the rail pressure down to 43psi and to no avail boost = 9:1 afr and car wont do anything. tried the boost controller and put the switch so it should run 25psi of boost to try to lean it out but only makes up to around 5-6psi due to the car running so rich.
everything seems to be fine plug wise, gonna test the coils and misc parts.
any idea on testing a map sensor to see whether or not its bad?
wastegate/bov/map sensor/fuel pressure all have their own vac source.
for my vac it goes brake booster to the 1/2 barb on the ho manifold. hose barb on pass side of the ho manifold goes to afpr and my boost gauge. tb fitting roughly 1/4 in size to my bov vac signal. slightly bigger than 1/4" barb to the wastegate, 1/2" barb using a vac cap. tapped oil/air seperator to check valve to middle ho manifold barb.
i have yet to go and do a boost leak test, shop is stupid busy and unfortunetly the beauty of being a shop owner is your stuff gets worked on last if ever
any insight/comments/shenanigans are more than welcome
Have you done any datalogs?
If so what does the map sensor show reading wise?
Sure not spark blow out?
FU Tuning
Addicted to meth wrote:Have you done any datalogs?
If so what does the map sensor show reading wise?
Sure not spark blow out?
i can email you a log, wish i wasnt so damn dumb with tuning. really wanting to go to a course for this and just learn even the basics.
im gonna change plugs as well and see if that might be it
yeah emal me a log and your config file to JMHZ2497@comcast.net
FU Tuning
Did this all start happening after a recent tune?
(Unrelated to a tune)
This may be WAY out on a limb because I don't have nearly enough info on what is happening but have you buy chance checked the injector driver? An easy way to do this is to hook up a noid light to the injector/s and see if perhaps at some point the light is on solid. The driver controls ground and while unlikely it is possible that the driver took a dump. The datalog may look fine as the numbers you see there for injector PW are simply a command not an actual.
(When)
Datalog would help in this case but at what point is this occurring vac/psi wise? Is it consistently at the same point or fluctuates?
(As far as testing the MAP)
What the data log to see if it is smoothly reading normal throughout the vac/psi range. To bench test it you will need a handheld vac pump.
BuiltNBoosted wrote:You rebuild your afpr?
Probably not this since he apparently has a way of monitoring this as it appears he made adjustments to it. Unless there is something occurring during driving and he is not able to monitor the psi (i.e. gauge in the cabin). Too much pressure can certainly cause the injectors to begin clipping and cause similar issues.
ASE Master Certified Automotive Technician
he told me, he can slowly bring it up to 7 grand no problem, no stutter, no surging nothing, as soon as he hits boost it goes pig rich and falls on its face.
whatever the problem is, sounds boost referenced to me.
CaliforniaDomestics wrote:Did this all start happening after a recent tune?
(Unrelated to a tune)
This may be WAY out on a limb because I don't have nearly enough info on what is happening but have you buy chance checked the injector driver? An easy way to do this is to hook up a noid light to the injector/s and see if perhaps at some point the light is on solid. The driver controls ground and while unlikely it is possible that the driver took a dump. The datalog may look fine as the numbers you see there for injector PW are simply a command not an actual.
(When)
Datalog would help in this case but at what point is this occurring vac/psi wise? Is it consistently at the same point or fluctuates?
(As far as testing the MAP)
What the data log to see if it is smoothly reading normal throughout the vac/psi range. To bench test it you will need a handheld vac pump.
BuiltNBoosted wrote:You rebuild your afpr?
Probably not this since he apparently has a way of monitoring this as it appears he made adjustments to it. Unless there is something occurring during driving and he is not able to monitor the psi (i.e. gauge in the cabin). Too much pressure can certainly cause the injectors to begin clipping and cause similar issues.
was running good and then just went to crap, no recent tuning or anything to that regard. only happens when i try to boost otherwise the car drives like a dream. injectors are just fine in regards to being within their means of duty cycle/operating pressure
I looked at the datalog, but saw nothing jump out. For sure happens right when boost comes on, or when map goes over 105kpa.
Try and flash your current tune ot the car and see what happens.
FU Tuning
Addicted to meth wrote:I looked at the datalog, but saw nothing jump out. For sure happens right when boost comes on, or when map goes over 105kpa.
Try and flash your current tune ot the car and see what happens.
i can reflash it again when i get to the shop, wonder what else might be the issue, maybe a bad map sensor?
LAFNGAS wrote:Addicted to meth wrote:I looked at the datalog, but saw nothing jump out. For sure happens right when boost comes on, or when map goes over 105kpa.
Try and flash your current tune ot the car and see what happens.
i can reflash it again when i get to the shop, wonder what else might be the issue, maybe a bad map sensor?
I orginally thought map sensor, but it seems to be working in the datalog.
Flash it again and then drive it and see how it does.
FU Tuning
I agree. Try reflashing one more time and see what it does.
ASE Master Certified Automotive Technician
I know my car isn't boosted, but I have had to reflash my cav after it has sat for a month or two. Mine would run very rich, for no reason at all. I would reflash my tune or even a stock tune, and it would go back to normal.
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
trying to flash it today once i get to the shop, appreciate the insight and help provided thus far guys!!
LAFNGAS wrote:trying to flash it today once i get to the shop, appreciate the insight and help provided thus far guys!!
i have not forgot about you Scott... Its just been REALLY hectic over the last 2 weeks, and moving this week....
P&P Tuning
420.5whp / 359.8wtq
QWK LN2 (P&P Tuning) wrote:LAFNGAS wrote:trying to flash it today once i get to the shop, appreciate the insight and help provided thus far guys!!
i have not forgot about you Scott... Its just been REALLY hectic over the last 2 weeks, and moving this week....
you were very forward when we talked, i understand and respect that, you have to take care of you & your family. i posted just seeing if there was something i mightve overlooked is all and more heads in the game the better chance i had to find a way to resolve it.
thanks again to everyone, flashed the car but no time to drive it, damn shop is stupid busy and running me ragged
why would the computer revert back to the stock tune? that makes no sense.
im saying its the map sensor. surely you have a few kicking around you can try....
I choose the technology built for land speed records... not the technology built to save on emissions and gas mileage.
-Z Yaaaa- wrote:why would the computer revert back to the stock tune? that makes no sense.
im saying its the map sensor. surely you have a few kicking around you can try....
I'm not saying it is reverting back to stock. But we have seen some issues with bad ECU's. a fresh flash will cure it for a few days.
FU Tuning
Addicted to meth wrote:-Z Yaaaa- wrote:why would the computer revert back to the stock tune? that makes no sense.
im saying its the map sensor. surely you have a few kicking around you can try....
I'm not saying it is reverting back to stock. But we have seen some issues with bad ECU's. a fresh flash will cure it for a few days.
That and just like any data transfer data bits can be lost in the transfer itself. Sometimes they just don't flash entirely correctly. Often times everything may seem perfectly fine until you come across a part of the tune per si where the data transfer issue occurred. This doesn't seem to happen very often but I have seen it happen and a simple reflash corrects the issue with no other changes.
ASE Master Certified Automotive Technician
well tried reflashing it and it still does it
hoping to get it in the shop and do some testing ie- boost leak and such
any idea on the map part # for the 2 bar if it is indeed pooched & any way to test it to see, we have a gm scan tool here but havent had time cause the shop is damn busy, i know its not an excuse but gotta make the $$ so the shop can run and get ahead
thanks for the help thus far!!!!!!!!!
Did u try to ve tune it again then re tune your pe afr multi. Then it you see a big change do a leak down test.
see ya!
havent tried to do anything other than reflash it, i gotta get it up to boost leak test it and do a couple other things
