Fuel problem please help
Fuel problem please help
first off im using the aps fuel system that comes with the kit with 650cc injectors. ill just post them email from the tuner please let me know what i should do to fix this..
get another fuel pump?
get the complete fuels system with rails?
ect.
thanks
Jimmy, I spend a couple hours tuning on the car tonight. Chased the tuning around quite a bit and finally decided to give up as you have a fuel system problem. It feels like the pressure is dropping. Also, the APS 550cc tune was actually running lean so are you sure you have 650cc injectors in there? And if so, are you sure the fuel system is set up to run the correct fuel pressure? So other than needing the tuning dialed in, something is going on with the fuel system for sure.
I got the AFR dialed in pretty good in the 11.0 to 11.6:1 range but it won't stay consistent. I can make it run 11.0:1 at the same boost and rpm but then also make it lean out to 13.5:1 at that same boost and rpm level – so there is a major inconsistent factor that will cause damage to the engine if it isn't taken care of. It has a lot to do with how hard the car is pulling. 3rd gear will lean out in mid range when it is pulling hard. 4th gear doesn't lean out as it doesn't pull as hard, 5th gear is fat. This tells you that the fuel system is on the edge and the difference of the Gforces is what is dropping the fuel pressure at the rail. I thought you said that you had upgraded rails, regulator on the rail and fuel pump setup. This has stock regulator up front and also stock fuel rails on it. Who did the fuel system?
Good news is it idles a lot better. Your WG is set at about 10 psi. I didn't tune any higher than that as I just don't trust the fuel system and I don't want to risk damaging the engine until that is fixed. If you can turn the boost down to 6-8 psi, it may work a lot better and be more stable but it will require rechecking or retuning at that level too because the tuning I did there was all part throttle tuning and it will be at WOT if your gates are set lower so that will effect the tuning. So the tune is on the lean side in the lower gears but rich in the higher gears. We will need to also make some changes in the parameters to try and help it run better and go in and out of open loop better. It also is a little hard to start as it puts a lot of fuel in during cranking.
FYI, looked into your wideband issue and the sensor is OK. Something is wrong with the gauge. Did you install that? May be a wiring issue if it never has worked or may just be a bad gauge. Sorry that wasn't just a simple sensor issue.
I would recommend not boosting or definitely not racing the car until it is fixed, especially when your AFR gauge is NOT working so you can keep an eye on things. It gets knock retard when it leans out so you don't want to damage an engine. I normally charge about $100/hr for street tuning but since we are going to have to get back in there and finish things up (depending on what changes you make on the fuel system – it may require some final tuning or it may require starting over) I'll just charge you $150 if you can pay cash
__________________
get another fuel pump?
get the complete fuels system with rails?
ect.
thanks
Jimmy, I spend a couple hours tuning on the car tonight. Chased the tuning around quite a bit and finally decided to give up as you have a fuel system problem. It feels like the pressure is dropping. Also, the APS 550cc tune was actually running lean so are you sure you have 650cc injectors in there? And if so, are you sure the fuel system is set up to run the correct fuel pressure? So other than needing the tuning dialed in, something is going on with the fuel system for sure.
I got the AFR dialed in pretty good in the 11.0 to 11.6:1 range but it won't stay consistent. I can make it run 11.0:1 at the same boost and rpm but then also make it lean out to 13.5:1 at that same boost and rpm level – so there is a major inconsistent factor that will cause damage to the engine if it isn't taken care of. It has a lot to do with how hard the car is pulling. 3rd gear will lean out in mid range when it is pulling hard. 4th gear doesn't lean out as it doesn't pull as hard, 5th gear is fat. This tells you that the fuel system is on the edge and the difference of the Gforces is what is dropping the fuel pressure at the rail. I thought you said that you had upgraded rails, regulator on the rail and fuel pump setup. This has stock regulator up front and also stock fuel rails on it. Who did the fuel system?
Good news is it idles a lot better. Your WG is set at about 10 psi. I didn't tune any higher than that as I just don't trust the fuel system and I don't want to risk damaging the engine until that is fixed. If you can turn the boost down to 6-8 psi, it may work a lot better and be more stable but it will require rechecking or retuning at that level too because the tuning I did there was all part throttle tuning and it will be at WOT if your gates are set lower so that will effect the tuning. So the tune is on the lean side in the lower gears but rich in the higher gears. We will need to also make some changes in the parameters to try and help it run better and go in and out of open loop better. It also is a little hard to start as it puts a lot of fuel in during cranking.
FYI, looked into your wideband issue and the sensor is OK. Something is wrong with the gauge. Did you install that? May be a wiring issue if it never has worked or may just be a bad gauge. Sorry that wasn't just a simple sensor issue.
I would recommend not boosting or definitely not racing the car until it is fixed, especially when your AFR gauge is NOT working so you can keep an eye on things. It gets knock retard when it leans out so you don't want to damage an engine. I normally charge about $100/hr for street tuning but since we are going to have to get back in there and finish things up (depending on what changes you make on the fuel system – it may require some final tuning or it may require starting over) I'll just charge you $150 if you can pay cash
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From: jeddah
Hi man i read through the email, and got bits out of it, but there r alot of questions to ask u if i was to try to help and i dont promiss i'm just another guy who whent through a project from zero.. so here it is..
1st of all we faced this problem b 4 on 1 of the Zs in here and it was the fule pump so thats the easiest to do. FYI out of 50 wellbro pumps u get 2 not working... and u will never know.
second of all if it wasn't the pump check the filter in the main fule feed after that 1 very IMPORTANT THING, make sure that the fule lines go like this (main feed devide into 2 and then into the rails then of the rails each go into the regulater, regulater pressure i'm guessing will be 45 psi and then 1 return from the regulater... Finaly the debaid on if ur injectors r 550cc or 650cc u can determin this just befor tuning choose 550cc injectors as u start tuning and if it doesn't mach then rechoose the sise of injectors to 650cc but i dont think u will reach this part. (not sure that u understood injectors bit but if u say it to the guy tuning ur car probably he will)
1st of all we faced this problem b 4 on 1 of the Zs in here and it was the fule pump so thats the easiest to do. FYI out of 50 wellbro pumps u get 2 not working... and u will never know.
second of all if it wasn't the pump check the filter in the main fule feed after that 1 very IMPORTANT THING, make sure that the fule lines go like this (main feed devide into 2 and then into the rails then of the rails each go into the regulater, regulater pressure i'm guessing will be 45 psi and then 1 return from the regulater... Finaly the debaid on if ur injectors r 550cc or 650cc u can determin this just befor tuning choose 550cc injectors as u start tuning and if it doesn't mach then rechoose the sise of injectors to 650cc but i dont think u will reach this part. (not sure that u understood injectors bit but if u say it to the guy tuning ur car probably he will)
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