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I just found a set of numbers I pulled from freeze frame data you might find interesting/telling_x000D_
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PO174_x000D_
TPS% 22.4_x000D_
RPM 2180_x000D_
Load 20.4_x000D_
MAF 5.91_x000D_
MAP 14.8_x000D_
Coolant 145F_x000D_
LTFT 25_x000D_
STFT 0_x000D_
LTFT2 25_x000D_
STFT2 0_x000D_
Speed 73mph_x000D_
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( gotta say I’m happy I can chuI understand what a MAP sensor is kind of but does 14.8 equal the amount of intake vacuum in inches of Hg? Since 29.6 is a perfect vacuum should it be 14.8 inches of Hg at 50% or am I just way out in left field grasping at straws?_x000D_
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Thanks y’allIf they charged you they’d have to marry it, I would have done the same thing if I’m honest._x000D_
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You may be onto something with fuel delivery as your numbers are positive which would indicate it’s adding fuel that could be due to a vacuum leak OR a lack ofSOLVED!
It took long enough, but I got it figured out. Ready for the answer? It was the Heater! Confused? Not exactly where you’d want to look, but when it gets cold outside and the heater decided to quit working, I had to figure out what was going on in a hurry…I need that HEAT!
Seems that I never truly understood the vacuum schematic for the vacuum lines for the heater controls, and neither did the guy that installed the V8. I had the vacuum ball hooked up to port that supplies vacuum to the heater control valve, and the heater control valve connected to the vacuum source ( engine ) which apparently was using too large of a vacuum hose. The large vacuum hose allowed the heater control valve to stay open because it was ..leaking vacuum! When I installed the proper sized hose because the original valve had broken and was leaking like a sieve, it closed the valve and turned off my heat. I was scratching my head at that one for a while…I just had heat before I “Fixed” it. Of course, what really had me scratching was the fact that the service engine soon light was coming on and going off randomly, and if I raced the motor under load, I’d start to get heat ( loss of vacuum allowed the valve to open up a little and allow heat to the core ).
Totally a LOL moment. I’m relieved it ultimately ended up being something so simple…but who’d think to look there for a vacuum leak?
SOLVED!
It took long enough, but I got it figured out. Ready for the answer? It was the Heater! Confused? Not exactly where you’d want to look, but when it gets cold outside and the heater decided to quit working, I had to figure out what was going on in a hurry…I need that HEAT!
Seems that I never truly understood the vacuum schematic for the vacuum lines for the heater controls, and neither did the guy that installed the V8. I had the vacuum ball hooked up to port that supplies vacuum to the heater control valve, and the heater control valve connected to the vacuum source ( engine ) which apparently was using too large of a vacuum hose. The large vacuum hose allowed the heater control valve to stay open because it was ..leaking vacuum! When I installed the proper sized hose because the original valve had broken and was leaking like a sieve, it closed the valve and turned off my heat. I was scratching my head at that one for a while…I just had heat before I “Fixed” it. Of course, what really had me scratching was the fact that the service engine soon light was coming on and going off randomly, and if I raced the motor under load, I’d start to get heat ( loss of vacuum allowed the valve to open up a little and allow heat to the core ).
Totally a LOL moment. I’m relieved it ultimately ended up being something so simple…but who’d think to look there for a vacuum leak?
well, perhaps I jumped the gun a bit. I still have a check engine light on…came back yesterday. I need to put my scanner on it and see what is going on. Didn’t notice anything loose when I redid the vacuum lines, but I can easily remove that from the system by simply plugging the vacuum line. Likely I’ll just end up getting new vacuum lines for the whole shebang and eliminate the possibility altogether.
well, perhaps I jumped the gun a bit. I still have a check engine light on…came back yesterday. I need to put my scanner on it and see what is going on. Didn’t notice anything loose when I redid the vacuum lines, but I can easily remove that from the system by simply plugging the vacuum line. Likely I’ll just end up getting new vacuum lines for the whole shebang and eliminate the possibility altogether.
sounds like your on the right track.have you rechecked your
fuel trim numbers? we would be interested in seeing them.
I did notice that your coolant temp was pretty low.keep
us posted on your progress. 😉sounds like your on the right track.have you rechecked your
fuel trim numbers? we would be interested in seeing them.
I did notice that your coolant temp was pretty low.keep
us posted on your progress. 😉Nope, haven’t looked at the fuel trim numbers yet. I’m replacing the transfer case on Wednesday, so I’m planning on using our good scanner at the shop to look at everything.
Nope, haven’t looked at the fuel trim numbers yet. I’m replacing the transfer case on Wednesday, so I’m planning on using our good scanner at the shop to look at everything.
I wouldn’t say you need to replace all the lines, just the bad ones if you find them. If they’re still pliable then they’re probably not an issue. It doesn’t hurt to look for vacuum leaks though. I’d first pull the codes to see what you have. It might be unrelated.
I wouldn’t say you need to replace all the lines, just the bad ones if you find them. If they’re still pliable then they’re probably not an issue. It doesn’t hurt to look for vacuum leaks though. I’d first pull the codes to see what you have. It might be unrelated.
I pulled the codes with my basic scanner, P0171 and 174 again, with 171 causing the freeze frame data to record. I need a better way to determine if I have a leak at the intake manifold or not. I’ve tried propane and carb cleaner to no avail. I have pulled the air cleaner off and my LTFT numbers come down. I can only think that removing the restriction of the air cleaner ( which is brand new, but still an aftermarket “cone” style…no oil ) removes some need for the engine to try to draw air through a vacuum leak somewhere. I saw something about hooking up a vacuum line to the PCV system by blocking off the PCV and the vent side hose to the intake horn and pulling a reading from the valve cover on the opposite side as the PCV. Supposedly I’d get a vacuum reading of the intake was leaking in the lifter valley. Somehow if that were the cause to the leak, it makes me wonder if that also wouldn’t be the cause of the buzz I’ve heard from the PCV valve. It would seem to me that if I were drawing an intake pulse vacuum through the block side of the intake, whilst the blowby from compression was trying to increase pressure at the same time, I’d have a “push/pull” effect on the PCV valve.
Does that make any sense? Not sure if I’m grasping at straws, giving myself an excuse to just pull the intake and replace the gaskets wholesale or if I’m either on something, or onto something.
I pulled the codes with my basic scanner, P0171 and 174 again, with 171 causing the freeze frame data to record. I need a better way to determine if I have a leak at the intake manifold or not. I’ve tried propane and carb cleaner to no avail. I have pulled the air cleaner off and my LTFT numbers come down. I can only think that removing the restriction of the air cleaner ( which is brand new, but still an aftermarket “cone” style…no oil ) removes some need for the engine to try to draw air through a vacuum leak somewhere. I saw something about hooking up a vacuum line to the PCV system by blocking off the PCV and the vent side hose to the intake horn and pulling a reading from the valve cover on the opposite side as the PCV. Supposedly I’d get a vacuum reading of the intake was leaking in the lifter valley. Somehow if that were the cause to the leak, it makes me wonder if that also wouldn’t be the cause of the buzz I’ve heard from the PCV valve. It would seem to me that if I were drawing an intake pulse vacuum through the block side of the intake, whilst the blowby from compression was trying to increase pressure at the same time, I’d have a “push/pull” effect on the PCV valve.
Does that make any sense? Not sure if I’m grasping at straws, giving myself an excuse to just pull the intake and replace the gaskets wholesale or if I’m either on something, or onto something.
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