123tom123tom Posted January 20, 2008 Share Posted January 20, 2008 right this is the story so far, i went bpu this week, my a/f ratio are all over. at idle 14.7-15.3 i have read this fine. but the problem is when i put the foot down it seems to go wappy it goes down to about 12 then up to 15/16.... now i know this is bad (running Lean) at boost, what do i need to do, or and another thing is when you take the foot off the loud peddle isnt it ment to go off the scale lean not rich like mine.. i am reading correctly the lower the number the richer it is. do i need to up the fuel pressure on the fpr, at the min it is at 35-40 psi never seems to hold. Link to comment Share on other sites More sharing options...
supra matt Posted January 20, 2008 Share Posted January 20, 2008 What fpr you got mate? sounds like this may be your problem if its not reading stable ! or you have a air leak . Link to comment Share on other sites More sharing options...
JustGav Posted January 20, 2008 Share Posted January 20, 2008 Why have you got an FPR for BPU? Go back to stock and see if you still have an issue. Link to comment Share on other sites More sharing options...
123tom123tom Posted January 20, 2008 Author Share Posted January 20, 2008 trying to get a stock one at the minute.... aeromotive fpr, what can i do mean while do you think upping the fuel pressure to 40 psi at static..... Link to comment Share on other sites More sharing options...
carl0s Posted January 20, 2008 Share Posted January 20, 2008 i am reading correctly the lower the number the richer it is. OOps, I'm talking rubbish. Yep you're right I think Link to comment Share on other sites More sharing options...
JustGav Posted January 20, 2008 Share Posted January 20, 2008 Correct.. The lower the number the richer it is. It is a ratio between fuel and air.. Therefore more fuel the smaller the ratio. Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted January 20, 2008 Share Posted January 20, 2008 right this is the story so far, i went bpu this week, my a/f ratio are all over. at idle 14.7-15.3 i have read this fine. but the problem is when i put the foot down it seems to go wappy it goes down to about 12 then up to 15/16.... now i know this is bad (running Lean) at boost, what do i need to do, or and another thing is when you take the foot off the loud peddle isnt it ment to go off the scale lean not rich like mine.. i am reading correctly the lower the number the richer it is. do i need to up the fuel pressure on the fpr, at the min it is at 35-40 psi never seems to hold. So your saying that once you put your foot down AFRs initially go to 12 and then go back up to 15/16 NOT GOOD! foot still on throttle and still making boost? oh and the going rich when you take your foot off the throttle is normal it Will go rich for a second or two then go lean 20.9 = no fuel. Link to comment Share on other sites More sharing options...
supra matt Posted January 20, 2008 Share Posted January 20, 2008 trying to get a stock one at the minute.... aeromotive fpr, what can i do mean while do you think upping the fuel pressure to 40 psi at static..... aeromotive good make so should not be that . try looking for air leaks Link to comment Share on other sites More sharing options...
Pete Posted January 20, 2008 Share Posted January 20, 2008 So your saying that once you put your foot down AFRs initially go to 12 and then go back up to 15/16 NOT GOOD! foot still on throttle and still making boost? I think this is the key bit. It should only go up to 15/16 when releasing the throttle. Link to comment Share on other sites More sharing options...
123tom123tom Posted January 20, 2008 Author Share Posted January 20, 2008 i have just been out in the car and set the fuel pressure slightly higher at idle about 43psi, with this my air fuel ratio are as follows, idle 14.7- 15.2 jumping about whilst normal driving jumps between 14.5-15.5 foot to the floor full boost goes to 10.4 and jumps around 11.1 does this sound better, but what about me having to raise the fuel pressure Link to comment Share on other sites More sharing options...
123tom123tom Posted January 20, 2008 Author Share Posted January 20, 2008 anybody got an opinion on my last post here Link to comment Share on other sites More sharing options...
AndyT Posted January 20, 2008 Share Posted January 20, 2008 Wez, Tricky, Ryan et al, check these probs regualarly mate. Don't worry. Link to comment Share on other sites More sharing options...
123tom123tom Posted January 20, 2008 Author Share Posted January 20, 2008 cheers i will wait for responce Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted January 20, 2008 Share Posted January 20, 2008 i have just been out in the car and set the fuel pressure slightly higher at idle about 43psi, with this my air fuel ratio are as follows, idle 14.7- 15.2 jumping about whilst normal driving jumps between 14.5-15.5 foot to the floor full boost goes to 10.4 and jumps around 11.1 does this sound better, but what about me having to raise the fuel pressure Sounds OK, 10.4 is a bit rich, 11.1 is OK if you have no form of ECU control, the only bit that worries me is the fact that it it jumps from 10.4 to 11.1 whilst still on full boost and flat to the floor, are you sure there is no drop in boost pressure when it goes to 11.1?? Link to comment Share on other sites More sharing options...
123tom123tom Posted January 20, 2008 Author Share Posted January 20, 2008 Think It Is The Fuel Pressure Regulator It Wont Hold Pressure Constant, It All Over It Even Read 60psi Earlier..... Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted January 21, 2008 Share Posted January 21, 2008 Which one is it? starting to sound like Dash Rendars problem. Link to comment Share on other sites More sharing options...
Wez Posted January 21, 2008 Share Posted January 21, 2008 Which one is it? starting to sound like Dash Rendars problem. Same make too, Aeromotive, these are normally fine though. Link to comment Share on other sites More sharing options...
Wez Posted January 21, 2008 Share Posted January 21, 2008 Think It Is The Fuel Pressure Regulator It Wont Hold Pressure Constant, It All Over It Even Read 60psi Earlier..... Where are reading the pressure from, surely not 60psi on a gauge in the engine bay. FYI you have put a capital at the beginning of each word Link to comment Share on other sites More sharing options...
JustGav Posted January 21, 2008 Share Posted January 21, 2008 Which one is it? starting to sound like Dash Rendars problem. Was just thinking that as well... wonder if it is worth seeing where they both reference pressure from? or if there is something else that is common with them. Link to comment Share on other sites More sharing options...
123tom123tom Posted January 21, 2008 Author Share Posted January 21, 2008 yes the gauge that is on the fpr has up toi 80 psi... this surely shouldnt make a difference to it staying constant though. also now i am getting pissed at bpu as the car wont start properly from cold, it starts, goes to about 1100 rpm stays as per usual then starts to drop and drop until it starts to cut out or cut out, as this is happening the aem gauge gets leaner and leaner untill it goes --- and then cuts. if i manually hold the revs at a 1000 rpm until it warms up slightly it becomes fine and runs normal at about 800rpm with 14.7-15.2 on the aem gauge its a mistery to me HELP PLEASE Link to comment Share on other sites More sharing options...
Wez Posted January 21, 2008 Share Posted January 21, 2008 yes the gauge that is on the fpr has up toi 80 psi... this surely shouldnt make a difference to it staying constant though. Correct but you also shouldnt be reading 60psi. Link to comment Share on other sites More sharing options...
123tom123tom Posted January 21, 2008 Author Share Posted January 21, 2008 any body no about the cold start problem,,,, am running lean on boost normal driving and idle is fine so what you think Link to comment Share on other sites More sharing options...
Wez Posted January 21, 2008 Share Posted January 21, 2008 Might be an idea to take a look in this thread, the issue sounds very similar. http://www.mkivsupra.net/vbb/showthread.php?t=132981 Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted January 21, 2008 Share Posted January 21, 2008 yes the gauge that is on the fpr has up toi 80 psi... this surely shouldnt make a difference to it staying constant though. also now i am getting pissed at bpu as the car wont start properly from cold, it starts, goes to about 1100 rpm stays as per usual then starts to drop and drop until it starts to cut out or cut out, as this is happening the aem gauge gets leaner and leaner untill it goes --- and then cuts. if i manually hold the revs at a 1000 rpm until it warms up slightly it becomes fine and runs normal at about 800rpm with 14.7-15.2 on the aem gauge its a mistery to me HELP PLEASE Just how lean is it reading when you start from cold and don't manually hold the RPM?? Link to comment Share on other sites More sharing options...
123tom123tom Posted January 21, 2008 Author Share Posted January 21, 2008 i have read that thred a million times lol... but i cant understand wheather it is exactly the same thing. my problem i think is the fpr, but what i am now asking is, would this cause the car to not start on cold starts properly ie when i started this morning it went to 1100rpm them i manually had to hold it there until the car got warm or it would just cut out and run lean off the scale --- am confused to hell now i just need a stock fuel pressure regulator and the metal ruturn line that screws into it, this i think will solve the problem.... or well i am on this little rant, how does the stock fpr account for the extra boost that is been produced at bpu, because it is not adjustable, how does it no to put that extra load of fuel in at a full 1.2 psi.... Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now