I just installed my lexus afm, walbro 255fuel pump, new fuel filter, and 550 injectors. Got it all on and cranked the car up. It is running rich, and my question is this. I have to drive it to the dyno about an hour away. Is it going to hurt it to drive it that far? I dont know how rich it is running, but it is idling just a bit off, cause it is trying to flood out I guess. I'm going to install my new intercooler this weekend and then take it next week to get tuned. I read that I need to have it at 11.5- 11.8 air/fuel mixture. Does this sound right? Any information will be very useful and appreciated. Thanks alot.
Car is running rich........
- Thread starter suprahero
- Start date
Hold on there my man, how do you know it's running rich? Goofy idle isn't unheard of with your setup. You may need to tweak the screw in the AFM. I also suggest you check the Vf signal to see if the ecu is trying to go lean. You need to verify the engine is really running rich. As long as it's running in closed loop it shouldn't be so check the O2 signal too.
Assuming it is rich (but not overly rich) driving an hour isn't going to hurt things. Your cat (if you have one) isn't going to like being fed a rich diet but it'll survive. Too rich is a different story though and could result in a meltdown. Also, how are you planning to tune? You didn't list anything that'd let you do that.
Assuming it is rich (but not overly rich) driving an hour isn't going to hurt things. Your cat (if you have one) isn't going to like being fed a rich diet but it'll survive. Too rich is a different story though and could result in a meltdown. Also, how are you planning to tune? You didn't list anything that'd let you do that.
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Thanks for posting Jetjock. I dont KNOW that it is running rich. I just thought with adding the new fuel pump and the 550 injectors that it would. I also thought I was smelling fuel by the exhaust while I was listening to it. It sounded like it was missing almost. It usually purrs a steady growl instead of a miss.
I'm going to the dyno and have them tune it with my safcii. They've been getting my air to fuel ratio pretty close. I wish I knew what you meant by checking my vf signal to see if the ecu is trying to go lean. I also dont know which way to turn the screw in my afm. Which way would I turn it to help lean it out? Thanks alot..........lol
I'm going to the dyno and have them tune it with my safcii. They've been getting my air to fuel ratio pretty close. I wish I knew what you meant by checking my vf signal to see if the ecu is trying to go lean. I also dont know which way to turn the screw in my afm. Which way would I turn it to help lean it out? Thanks alot..........lol
Ah, you have a safc...I missed that. Well, if you smell unburnt fuel at the tailpipe it may be running rich. Is the the pipe sooting up? Have a wideband? What's it say?
Changing the the fuel pump doesn't change fuel pressure unless you've installed an AFPR and messed with it. The Lex AFM and 550s should in theory cancel each other out but you may need to tweak the AFM screw to "fool" the ecu a bit. You can tweak it while watching Vf.
Measure the Vf signal with a voltmeter in the diag block. Measure between Vf and E1. If it's 5 volts the ecu is trying to enriching the mixture, if it's 0 volts it's trying to lean it. There are 5 voltage levels in all. It's not a bad thing to be a tad lean at idle but when cruising Vf should be in the middle. Vf doesn't tell if the engine is lean or rich in the direct sense, only what the ecu is currently trying to do to make the mixture correct. It's the fuel trim signal.
You can also use Vf to check your O2 cross counts by jumpering T and E1 but I prefer to scope the O2 signal itself, also located in the diab block. (If all you have is a DMM use Vf). With T and E1 jumpered and the engine at 2000 rpm or so your O2 sensor should cross count at least 8 times in 10 seconds. Vf can also be report if a code has been set but you have the check engine light for that.
Changing the the fuel pump doesn't change fuel pressure unless you've installed an AFPR and messed with it. The Lex AFM and 550s should in theory cancel each other out but you may need to tweak the AFM screw to "fool" the ecu a bit. You can tweak it while watching Vf.
Measure the Vf signal with a voltmeter in the diag block. Measure between Vf and E1. If it's 5 volts the ecu is trying to enriching the mixture, if it's 0 volts it's trying to lean it. There are 5 voltage levels in all. It's not a bad thing to be a tad lean at idle but when cruising Vf should be in the middle. Vf doesn't tell if the engine is lean or rich in the direct sense, only what the ecu is currently trying to do to make the mixture correct. It's the fuel trim signal.
You can also use Vf to check your O2 cross counts by jumpering T and E1 but I prefer to scope the O2 signal itself, also located in the diab block. (If all you have is a DMM use Vf). With T and E1 jumpered and the engine at 2000 rpm or so your O2 sensor should cross count at least 8 times in 10 seconds. Vf can also be report if a code has been set but you have the check engine light for that.
Kudos to isnms...you can't ask for better than that.
PM me if you need to. You should get one of those voltage levels and never higher than 5 so you're doing something wrong. Check the voltmeter across the battery.
PM me if you need to. You should get one of those voltage levels and never higher than 5 so you're doing something wrong. Check the voltmeter across the battery.
yes vf1 and e1. i updated my pic in the previous post.
also this is a good read: http://alflash.narod.ru/vf1.htm
edit: thanks jetjock, i appreciate that
also this is a good read: http://alflash.narod.ru/vf1.htm
edit: thanks jetjock, i appreciate that
I have a 1991 and in the diag. it has a vf1 and a vf2 and the e1. I think I figured it out though. It just read 1.6 and would go to zero if I revved it up a little. Thanks isnms and Jetjock. I really do appreciate your help.
Remember, if Vf is in range it doesn't neccesarily mean the engine is running rich or lean, it only means the ecu is working "harder" to make things right. Don't worry so much about idle but it it's 0 or 5 volts under steady state load that needs to be resolved.
isnms:you're welcome....and that update makes it all the better
isnms:you're welcome....and that update makes it all the better
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Can't I adjust it with my safcii instead of the screw in the lexus afm? The people that are going to dyno it have wideband o2 and everything that I need to tune it with. They even video it and put it on a disc for 15.00 so I can try and upload it on here.
I guess you could try that. Not sure if that'll help with the idle though. I don't have a safc so I'm not familar with it. I have the same setup you do though and don't have any problems. In fact my car runs opposite your's at idle. I let it run a little rich at WOT because I'm not there much. Maybe the safc is the problem? When start hanging stuff the EFI system it has to be setup right.