Topic: split second ftc-1

[sharpxmen]

ok, basic troubleshooting would require to identify the problem and not try to work around it

so I would do this
 1. try to take the FTC out and use the stock MAP sensor
 2. leave the FTC in and use the stock injectors
 3. if still doing it with either option 1 or 2 use both the stock MAP and stock injectors, if still an issue with that low rpm lean factor then it's not the FTC or the new injectors and it's something else.

if #1 fixes it then it's an issue with the FTC (so focus on troubleshooting that), if #2 fixes it then you need to figure out what's wrong with the injectors.

You really _need_ to determine what's causing the problem, otherwise you're shooting blind and it's unlikely to fix it unless you get really lucky, it's not a fine-tuning matter it's a problem that needs to be fixed first before you get to that stage. Not intending to give you hell but with all the time you wasted by trying to work around this issue you could have performed those 3 basic tests by now. It could also be a timing issue as well, and that can also be tested by not using the FTC timing connections (lean reading can also mean that the fuel is not burned completely and not that there's not enough fuel, it's the amount of oxygen in the exhaust that is measured by the O2 sensor, less burned fuel means more oxygen remaining)

[moparstroup]

gonna remove ftc after supper and use oem map and timing. that i can do tonight. injectors are a job due to the way they are bolted through the intake. the manifold must come off and i dont think that is the cause since both injectors do the same thing. but your right i will do that over the weekend.

[sharpxmen]

gonna remove ftc after supper and use oem map and timing. that i can do tonight. injectors are a job due to the way they are bolted through the intake. the manifold must come off and i dont think that is the cause since both injectors do the same thing. but your right i will do that over the weekend.

can't wait to hear if it does the same or not. 

[moparstroup]

all wiring back to stock and still does it,  injectors still 30# but  give me your thoughts on something. i plugged every vac line and still in open loop it it goes way lean on tip in with moderate throttle load makes is way worse like stoppping on a hill then trying to pull out. open loop idles little lopey at 12.5 afr (bigger injectors) tip in way lean 15-16 then runs good till 2000 then real lean again. didnt try boost. closed loop it was getting to stoich or close to it but did the same thing at tip in and 2000rpm. along with this just like before when under boost i get a VERY strong raw fuel smell and i dont think it comes from the exhaust although it might. have back window out. is there anything that could be wrong with the supercharger that might be related? by the way the last owner complained of raw fuel smell under boost too. also on tip in it looses most to all vacuum and under load does go into boost at less than 1500 rpm sometimes as low as 1000. that raw fuel smell will happen even when afr is 14.7 + or - a few tenths. i will take the manifolds back off and change out injectors again this weekend. on a n/a engine it would get so much air from vacuum, is there something in the blower (the vacuum diaghram in the back maybe), that keeps it from creating a lean condition just by the fact that the blower is running  on top of the intake. i dont see how the map reads manifold vacuum correctly if its on top of the blower. maybe its under the throttle plates. i am guessing me putting the stock injectors in will only tell me if the other ones are no good because they are going to be too small to go forward with i assume.  got my shop manual out and read up on tps and i think its fine either way it just measures the difference between what the computer is told is closed then something like 2.806 volts difference to wot and there is an upper limit of 4.7 volts i think which gives a lot of room to make min tps what ever it happens to be. anyway if i understand it right the computer sees  voltage change not actuall voltage. anyway thats where i am i will chime back in after oem inj are in or if s/sec has a revelation.

[sharpxmen]

i dont see how the map reads manifold vacuum correctly if its on top of the blower.

it is under the throttle butterfly, there's always vacuum there unles you press the gas pedal.

the bypass valve should open when the throttle is closed and should progressively open based on your throttle opening, the vac line for that valve should be connected between the t/b and the supercharger, not after the s/c (just in case you want to check) - things that can go wrong with it: vac line connected in the wrong place, tear in the membrane (not working/not holding vacuum), bad pressure (vacuum) setting on it if it's adjustable.

I'd put the stock injectors back on and test again, then if all good add the FTC back on. What if the injectors are not compatible, just taking a wild guess here - are you sure they are high impedance? what about the size (lb/hr)? or maybe they just squirt like crazy. you have a set of 24lb/hr injectors, that would be the next thing i would try once you tested the stock injectors and maybe after that if all checks out go on a junkyard hunt for larger ones.

seems that you're on the right track now, just keep eliminating possible problems until you get to the root cause - don't try and jump ahead though, 1 step at a time.
if it still does it with the stock injectors then the next thing is the supercharger, intake, fuel rail assembly (put the stock ones back in) - worst case scenario (or maybe best case scenario depending how you look at it) will still have the same issue once you return all back to stock which means then it's something unrelated to FTC/Supercharger/Intake/Fuel Rail/Injectors. Keep at it, you'll get it resolved, you already won a battle by eliminating FTC as a possible issue.

[sharpxmen]

got my shop manual out and read up on tps and i think its fine either way it just measures the difference between what the computer is told is closed then something like 2.806 volts difference to wot and there is an upper limit of 4.7 volts i think which gives a lot of room to make min tps what ever it happens to be. anyway if i understand it right the computer sees  voltage change not actuall voltage.

i think it reads voltage and not voltage differential, if it was a diff the FSM would specify a loose margin for the closed throttle position (between 0.2 and 1 volt for example). It is very specific on the requirement so that kindof proves this point.

on a n/a engine it would get so much air from vacuum, is there something in the blower (the vacuum diaghram in the back maybe), that keeps it from creating a lean condition just by the fact that the blower is running  on top of the intake.

this one i didn't get at all, what do you mean by "it would get so much air from vacuum"?

to answer the second part - not sure what you mean by keeping it from creating a lean condition, but here's my answer to that based on what i guese you're asking: if you go in boost with partially open throttle you'd have a problem when running the stock map sensor as you'd see some vacuum between the t/b and the supercharger and in reality you're way passed that point, that's why for these tests i wouldn't go in boost at all - you could take the stock map sensor off the t/b and connect it to the same port the ftc was connected (under the supercharger), that would give you a more accurate reading but would still be limited to 1 bar (no boost reading), it's fine for testing but not as a permanent solution of course. without boost the stock location is good enough for troubleshooting the problem.

[moparstroup]

according to scan tool it read the same at 1.0 volt as it does at .4 volt when you reset min tps it pics that voltage to start from and reads it at throttle opening 0% and it detects wide open throttle after it has changed by a certain percent weather you start at .4 or 1.0 it just pushes the wot higher by .6 i think i verified that last night when i checked it with 2 different tbodies. im not sure though i convinced myself that i was wrong all along but who knows. who ever designed this intake is a knuckle head. you must remove the eshaust manifold to acess the bults comming up through to fuel rail. thats my project for tonight. stinking hot out there upper 80's today.

[sharpxmen]

according to scan tool it read the same at 1.0 volt as it does at .4 volt when you reset min tps it pics that voltage to start from and reads it at throttle opening 0% and it detects wide open throttle after it has changed by a certain percent weather you start at .4 or 1.0 it just pushes the wot higher by .6 i think i verified that last night when i checked it with 2 different tbodies. im not sure though i convinced myself that i was wrong all along but who knows. who ever designed this intake is a knuckle head. you must remove the eshaust manifold to acess the bults comming up through to fuel rail. thats my project for tonight. stinking hot out there upper 80's today.

if your scan tool reports 0% throttle then it must be resetting the min value so i guess it doesn't matter.

that is weird to have to remove the manifold to take the rail out, i would think it's easier to pull the intake rather than the exhaust (actually i'm pretty sure it is easier that way).

[moparstroup]

dang sharp your right. last time i had to drill and weld bung on pipe, dont have to mess with that now. boy do i feel dumb

[moparstroup]

googled 2000 rpm stumble in jeep tj and there is a lot of people out there with this problem but non exactly. funny how it showes up 2000 rpm though. wonder if at 2000 rpm if the controller does some type of baseline check or something. several issuses showed up anything from 02 sensors to cam and crank sensors to tps and clockspring issues all surfacing at 2000 rpm. i found the post about the fuy with my supercharger and his list of parts he replaced trying to fix the 2000 stumble. one line said he tried replacing stock injectors with 30# new for racing injectors...  i am at a stand still jeep is parked outside and its rained yesterday and today and calling for it tomarrow . i am putting it all back to stock so my son can take his date to the prom in it. then back together again and keep going after that

[moparstroup]

put it all back to stock and it runs perfect no hesitations anywhere leaving it there for a week or so so my son can take it to prom,then back to drawing board, i have an old friend mike who is an engineer for chrusler and he is looking into why this is happening. see if he can shed some light,

[moparstroup]

sharp what do you think about that intake. the injectors on my stock manifold tilt towards the head and inject fuel into the cyl head. my intake (heard someone call it a clifford intake) the injectors sit considerably further back and point straight down not towards cyl head, you reused your intake so you can also reuse your injector rail and dampner and your injectors are in a better location. any thoughts. did you modify your intake? wanna sell it?

[sharpxmen]

my s/c mount is built to be installed on the a/c compressor support (above the alternator), then piping over to the intake, only thing that was modified on the intake is the inlet diameter, won't work on yours. if those injectors spray straight down that's a stupid intake, it's fine at high rpm but i'm pretty sure will cause problems at low air velocity (idle and around that), only problem is that you don't know for sure that was the cause of your issues. If you're certain the intake is the problem you can buy a stock one from the j/y and modify it at a machine shop that has an a/c tig welder, i could make one for you but i don't think you'd be happy with the price (will take some designing, machining, welding and then machining again + shipping of your clifford over and shipping the 2 back to you will make it fairly expensive in the end). You should still test those stock injectors with this intake to figure out if that works, you might have a surprise there (if it works fine with stock injectors then it's not the intake)

[moparstroup]

i see. and i agree bad design but cause of my 2000 rpm stumble,not likely.( IMHO) and as stupid as the intake design is it must have worked on somones. i think i will try and put the odd fuel rail with no dampner on the oem setup to see if there is any difference. next week after prom.

[sharpxmen]

i see. and i agree bad design but cause of my 2000 rpm stumble,not likely.( IMHO) and as stupid as the intake design is it must have worked on somones. i think i will try and put the odd fuel rail with no dampner on the oem setup to see if there is any difference. next week after prom.

before you swap the intakes again,
how easy is to add the ftc1 back in?

just thinking you could try the 30# injectors on the stock intake without the supercharger, should be easy to just pull the fuel rail out and swap the injectors and use the base map they sent you with the ftc1 installed - should work as with the s/c on but without boost, good test to eliminate the intake design or anything related to the s/c install before moving forward.