S5 FC w/Tii Swap, multiple bad idle conditions
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S5 FC w/Tii Swap, multiple bad idle conditions
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Mild Streetport
Walbro Fuel Pump
Racing Beat Turbo Back with Presilencer
Had a Fuel Cut Defender but removed
Bought this car around a month ago. Vehicle had trouble starting, would keep trying to turn over but would not go unless you played with the throttle a bit. Would get car running but would stall out if not given gas. Found around 10 vacuum leaks over various hoses. Smoke tested vehicle, did the carb cleaner trick and couldn't find anymore. Idle would surge if it decided to hold. Adjusted TPS multiple times, always warmed up, used the Voltage and Resistance methods to no avail. The only way the surge would go away was if I raised the idle by way of throttle or if I turned the idle adjust screw on the back of the intake down. It still never sounded completely right but the vehicle was finally idling. The surges became slower and it idled out. If I turned the lights on, idle would drop, if I turned on the ac the vehicle would stall unless I gave it more gas. Decided to take it out to potentially warm it up even more and do an additional adjustment to TPS but was not very far off. Today I cleaned all the grounds outlined on Aaron Cake's website. Still have difficulty starting unless I try to give the vehicle gas around 80% throttle. Does not go into any warm up cycle at all although, if I remember correctly, it used to before I adjusted the idle all the way down. Is there an adjustment for the bac, appears to be an S5 with no adjustment. Any insight would be greatly appreciated.
Mild Streetport
Walbro Fuel Pump
Racing Beat Turbo Back with Presilencer
Had a Fuel Cut Defender but removed
Bought this car around a month ago. Vehicle had trouble starting, would keep trying to turn over but would not go unless you played with the throttle a bit. Would get car running but would stall out if not given gas. Found around 10 vacuum leaks over various hoses. Smoke tested vehicle, did the carb cleaner trick and couldn't find anymore. Idle would surge if it decided to hold. Adjusted TPS multiple times, always warmed up, used the Voltage and Resistance methods to no avail. The only way the surge would go away was if I raised the idle by way of throttle or if I turned the idle adjust screw on the back of the intake down. It still never sounded completely right but the vehicle was finally idling. The surges became slower and it idled out. If I turned the lights on, idle would drop, if I turned on the ac the vehicle would stall unless I gave it more gas. Decided to take it out to potentially warm it up even more and do an additional adjustment to TPS but was not very far off. Today I cleaned all the grounds outlined on Aaron Cake's website. Still have difficulty starting unless I try to give the vehicle gas around 80% throttle. Does not go into any warm up cycle at all although, if I remember correctly, it used to before I adjusted the idle all the way down. Is there an adjustment for the bac, appears to be an S5 with no adjustment. Any insight would be greatly appreciated.
Last edited by danger1523; 08-10-16 at 10:47 PM. Reason: Posted Prematurely
#2
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A turbo BAC has a screw located in a hole that is accessible (BAC helps to start the car). You possibly have a clogged primary injector or two (they are used to start and idle). You also might have low fuel pressure which a fuel gauge placed inline would determine that possibility. Could have a faulty AFM as well. You could also check for error codes to possibly help diagnose things. Other things causing a hard start would be low compression or a coolant seal gone bad. And adjusting the TPS requires the car to be driven for 20 minutes or so to warm it up (idling takes an awfully long time).
Last edited by satch; 08-10-16 at 11:05 PM.
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Satch! I just read through an incredibly long and detailed no-start thread you were a part of six years ago where BravePotato couldn't start his swap. I'm trying to think of all the things I've done to remedy this since my post. I removed the upper intake manifold, again, today because it appeared as though my throttle was broken up and sticking. Clean up the throttle body and go over it in my spare time as a maintenance procedure. The thermowax was stuck, crudded up with coolant chunks, so I flushed that out, disassembled it, stuck it in the freezer and confirmed it was properly moving again.
I performed the resistance adjustment on the car after a 20 minute drive home, went to redline once to try to clear it out.
I just replaced the UIM gasket last time I had it off to plug a vacuum hose back into the front rotor oil injector, it had a tear in it (the gasket) when the intake slipped and split it, I installed it as it was since the old one was brittle and I just got this one in. Sprayed carb cleaner around it while running and it didn't raise the idle at all. When I removed the manifold today it was cracked (again, the gasket) in another section between the first two ports. So now I also need a new UIM. I also have a noise in the exhaust closer to the manifold, no especially worried about it. Doesn't exactly sound like a leak at the manifold, not too much of a concern of mine. The 02 sensor shouldn't have much to do with startup even if there's a bit more air getting to it, could explain part of my rich condition. No codes for that.
I unplugged the AFM and the car nearly died out before I could get the plug back in, it also ran poorly when I manualyl pushed the plunger.
The only error codes I had were for the BAC which could have been when I unplugged it to see how the car ran, it almost stalled out. I'm not sure was the proper test for the BAC is, I found that screw you spoke of today. I also had codes for two of the emissions parts. LLL, LLL SSS and LLL Sx8 . Sorry to write the morse code right now. I was hoping a thermosensor would come up, I checked it, good connection, good pin tension. Obviously no code. Thought it was causing a rich startup.
My question now is why would holding the throttle in a certain area cause the vehicle to start to almost crank? There are plenty of times when it starts to almost start and then defaults to a normal cranking. I thought if the vehicle was stuck in a rich condition that opening the throttle provided more air, bringing the mixture to to its proper place. Although opening the throttle would pull more air, pull on the AFM and causing more fuel in a never ending loop of hell. IIC
Also, where should a Fuel Pressure Gauge be put? Is after the Fuel Filter fine? I hope this was detailed enough. I've been at it a few nights a week. Sorry for the delayed reply, I apparently don't get the updates to my email
I performed the resistance adjustment on the car after a 20 minute drive home, went to redline once to try to clear it out.
I just replaced the UIM gasket last time I had it off to plug a vacuum hose back into the front rotor oil injector, it had a tear in it (the gasket) when the intake slipped and split it, I installed it as it was since the old one was brittle and I just got this one in. Sprayed carb cleaner around it while running and it didn't raise the idle at all. When I removed the manifold today it was cracked (again, the gasket) in another section between the first two ports. So now I also need a new UIM. I also have a noise in the exhaust closer to the manifold, no especially worried about it. Doesn't exactly sound like a leak at the manifold, not too much of a concern of mine. The 02 sensor shouldn't have much to do with startup even if there's a bit more air getting to it, could explain part of my rich condition. No codes for that.
I unplugged the AFM and the car nearly died out before I could get the plug back in, it also ran poorly when I manualyl pushed the plunger.
The only error codes I had were for the BAC which could have been when I unplugged it to see how the car ran, it almost stalled out. I'm not sure was the proper test for the BAC is, I found that screw you spoke of today. I also had codes for two of the emissions parts. LLL, LLL SSS and LLL Sx8 . Sorry to write the morse code right now. I was hoping a thermosensor would come up, I checked it, good connection, good pin tension. Obviously no code. Thought it was causing a rich startup.
My question now is why would holding the throttle in a certain area cause the vehicle to start to almost crank? There are plenty of times when it starts to almost start and then defaults to a normal cranking. I thought if the vehicle was stuck in a rich condition that opening the throttle provided more air, bringing the mixture to to its proper place. Although opening the throttle would pull more air, pull on the AFM and causing more fuel in a never ending loop of hell. IIC
Also, where should a Fuel Pressure Gauge be put? Is after the Fuel Filter fine? I hope this was detailed enough. I've been at it a few nights a week. Sorry for the delayed reply, I apparently don't get the updates to my email
#5
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You would place the fuel pressure gauge in line after the filter would be one choice.
http://fc3spro.com/TECH/HOWTO/ERRORC...KI/kerror.html
http://fc3spro.com/TECH/HOWTO/ERRORC...KI/kerror.html
Last edited by satch; 08-30-16 at 09:20 PM.
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I will do this tomorrow, any chance the sticking thermowax could cause an issue? It's been pretty hot here consistently so even if it was stuck in the hot position would it be that bad of a start up?
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Sorry that I didn't catch their colors, just saw a random white 2-pin attached to the lower injector harness that could reach to a connector of the bac harness. Plugged them in, no change today. Adjusted the bac, did not help with idle issue. Definitely have to look into the fuel pressure, I'm wondering if a stuck injector could be to blame, plugs are black
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Some of the codes you provided didn't make sense so what are their numbers. Two of them appeared to be 30 and 33 which are emissions related. Was the last one #38? And what are the wire colors. And if your spark plugs are black then that is either too much fuel, not enough spark or perhaps both.
And when adjusting the BAC the initial set coupler needs to be jumpered.
And the idle speed needs to be below a certain threshold for some of the idle speed adjustments to work.
And when adjusting the BAC the initial set coupler needs to be jumpered.
And the idle speed needs to be below a certain threshold for some of the idle speed adjustments to work.
Last edited by satch; 08-31-16 at 11:35 PM.
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I'll get back to you on the colors today, I've changed the plugs and the wires already, so what else could that be? Yes the last code was #38. What do you mean "the initial set coupler"
Last edited by danger1523; 09-01-16 at 08:50 AM.
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When setting the idle speed, the BAC will compensate changes made to a change when idle speed adjustments are made, thus to prevent the BAC from interfering, the coupler needs to be grounded. The coupler is a single wire diagnostic connector located near the lead coil (wire is Orange).
And what actually is your idle speed.
And what actually is your idle speed.
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It doesn't surge but it never seems to be idling at the same speed. Every time I start it the resting idle differs slightly. The throttle sticks, sometimes high, sometimes low
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I've smoke tested it and covered all of them, finally. The vehicle WILL NOT start unless I find a sweet spot in the throttle
I should check the timing, although I doubt it'd start at all if it was off
I should check the timing, although I doubt it'd start at all if it was off
Last edited by danger1523; 09-01-16 at 12:24 PM.
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Black with a white tracer, then it appears to be a brown or a red with a yellow tracer for the black male connector, the white female connector is black with brown and a black wire.