Nothing left to check? VP 5.7GSI wont start - good fuel pressure, good ecm, wiring
#351
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I want to know what color plug in do you have that is for the MAP sensor
Next can you read the numbers on your MAP sensor - the new one and the one you had when the engine ran good ? I want to know if there is a 039 in which means a 1 bar MAP sensor. this should be stamped on the backside of the MAP sensor not the side the vac hose connects to the MAP sensor. Look at both MAP sensor or how many you bought and installed.
Next can you read the numbers on your MAP sensor - the new one and the one you had when the engine ran good ? I want to know if there is a 039 in which means a 1 bar MAP sensor. this should be stamped on the backside of the MAP sensor not the side the vac hose connects to the MAP sensor. Look at both MAP sensor or how many you bought and installed.
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Correct, it's green. I can't make out the numbers now it's too dark. But it seems that if my pulse width is too narrow, as you said, then the only reason my engine is running is because the TJ 11 injextors flow double the fuel (round about) what the factory ones do. I will put the factory ones back in tomorrow but it won't help. It doesn't start or stay running with those
#354
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I believe the green connector can only connect to the 1 bar MAP sensor. so I believe you have that installed. Look for 039 stamped on the MAP sensor back side. the other side might have PBT GF30.
The injectors that you had in when the engine ran good what are the GM parts number that is stamped or marked on the tops of them. If I recall it should be a 25 number but I can not remember the rest.
IMO those were the ones I was saying someone might have jacked them up by testing them. Those are the injectors when the engine ran correctly is this correct ? If so what is the number on them again I think it starts with a 25?????
The injectors that you had in when the engine ran good what are the GM parts number that is stamped or marked on the tops of them. If I recall it should be a 25 number but I can not remember the rest.
IMO those were the ones I was saying someone might have jacked them up by testing them. Those are the injectors when the engine ran correctly is this correct ? If so what is the number on them again I think it starts with a 25?????
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I believe the green connector can only connect to the 1 bar MAP sensor. so I believe you have that installed. Look for 039 stamped on the MAP sensor back side. the other side might have PBT GF30.
The injectors that you had in when the engine ran good what are the GM parts number that is stamped or marked on the tops of them. If I recall it should be a 25 number but I can not remember the rest.
IMO those were the ones I was saying someone might have jacked them up by testing them. Those are the injectors when the engine ran correctly is this correct ? If so what is the number on them again I think it starts with a 25?????
The injectors that you had in when the engine ran good what are the GM parts number that is stamped or marked on the tops of them. If I recall it should be a 25 number but I can not remember the rest.
IMO those were the ones I was saying someone might have jacked them up by testing them. Those are the injectors when the engine ran correctly is this correct ? If so what is the number on them again I think it starts with a 25?????
The part number you are thinking about (GM part number) is 25170301. I ordered those from a fuel injection guy, but they are really hard to find. Unfortunately one was bad out of the box, and here's the thing.... I know my eye isn't a calibrated instrument, but I had one Tj 11, and the one new 25170301 side by side in the pod... I didn't see any noticeable difference in spray.
Lastly, BUP - you said my injector pulse widths are far too narrow. Since this is a function of the ECM, and not the injector, doesn't this all point back to a bad ecm again? Are there any published testing procedures or default parameters for injector pulse width? If the ecm is receiving proper readings from the map, ECT, IAT, TPS, but it's still producing the wrong pulse width, to me that sounds like a bad ecm.
However that being said, you mentioned my map sensor readings are off based on the rpms... But they are NOT off based on vaccum. My engine vaccum increases as I open the throttle. I remember being told at one point that this is the wrong behavior? But my cam timing is good, compression is good, and I sprayed a ton of carb cleaner around the intake and had no increase in rpm that would indicate a leak.
#356
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In neutral and slowly inceasing throttle , many engines increase vac a little.. So....I disagree with some others on this.
In gear , foot on brake (impossible in boat) to create load, applying throttle will decrease vac.
Boat, in the water, in gear, applying more throttle will reduce intake vacuum.
In gear , foot on brake (impossible in boat) to create load, applying throttle will decrease vac.
Boat, in the water, in gear, applying more throttle will reduce intake vacuum.
Last edited by SB; 05-25-2015 at 07:28 AM.
#357
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The part number you are thinking about (GM part number) is 25170301. I ordered those from a fuel injection guy, but they are really hard to find. Unfortunately one was bad out of the box, and here's the thing.... I know my eye isn't a calibrated instrument, but I had one Tj 11, and the one new 25170301 side by side in the pod... I didn't see any noticeable difference in spray.
You, however, are not going to visually see the fuel volume difference between the two. NO way.
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SB - would it be possible for me to send you my factory two injectors, and the one working GM injector I just bought, and have all three flow tested at 30 psi? My thought is, if the "known good one" flows the same as the two factory ones, then I assume they are all good.
Truthfully, as we have eliminated nearly all other possibilities, I am starting to think I need to have the ECM re flashed. If it's receiving all the right data, but interpreting it wrong, that sounds like a software issue, not hardware. Since the ecm is just acting like a grounding device, and we know that portion of it works, I don't see a reason to replace it.
SB - would it be possible for me to send you my factory two injectors, and the one working GM injector I just bought, and have all three flow tested at 30 psi? My thought is, if the "known good one" flows the same as the two factory ones, then I assume they are all good.
Truthfully, as we have eliminated nearly all other possibilities, I am starting to think I need to have the ECM re flashed. If it's receiving all the right data, but interpreting it wrong, that sounds like a software issue, not hardware. Since the ecm is just acting like a grounding device, and we know that portion of it works, I don't see a reason to replace it.
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Also, one thing in addition to above. BUP - fuel is in the fuel pump vent line. It's not full, but if I take it off, it will drip a few drops out. It's wet. Does that mean anything?
I plugged it and took it off, still runs the same. I also just put the one good GM injector that the guy sent me, and one of my original Injextors in, and it just won't stay running. I warmed it up on the tj11's.
as soon as the computer leans the pulse width out it dies
I plugged it and took it off, still runs the same. I also just put the one good GM injector that the guy sent me, and one of my original Injextors in, and it just won't stay running. I warmed it up on the tj11's.
as soon as the computer leans the pulse width out it dies
Last edited by nunnink23; 05-25-2015 at 11:14 AM.
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QUOTE=nunnink23;4308260]I will check the map sensor part number when I get to the boat in an hour. The part number on the old Injectors (original with the boat) have no part number on them. Unless I am a fool and missing them, but i can't make out any number, not even remains of an old one.
The part number you are thinking about (GM part number) is 25170301. I ordered those from a fuel injection guy, but they are really hard to find. Unfortunately one was bad out of the box, and here's the thing.... I know my eye isn't a calibrated instrument, but I had one Tj 11, and the one new 25170301 side by side in the pod... I didn't see any noticeable difference in spray.
Lastly, BUP - you said my injector pulse widths are far too narrow. Since this is a function of the ECM, and not the injector, doesn't this all point back to a bad ecm again? Are there any published testing procedures or default parameters for injector pulse width? If the ecm is receiving proper readings from the map, ECT, IAT, TPS, but it's still producing the wrong pulse width, to me that sounds like a bad ecm.
However that being said, you mentioned my map sensor readings are off based on the rpms... But they are NOT off based on vaccum. My engine vaccum increases as I open the throttle. I remember being told at one point that this is the wrong behavior? But my cam timing is good, compression is good, and I sprayed a ton of carb cleaner around the intake and had no increase in rpm that would indicate a leak.[/QUOTE]
Nun i hate to interupt your train of thought here but stay with BUP he is diagnosing your entire system not just the map but the whole system they (ect,,map,,,mat) are all interelated simple but very confusing. Let him trouble shoot the system his way this can be frustrating enough by itself say less for someone taking it all over the place. Now as to your injectors there all wrong (ebay right) and no you cannot see any difference in pulse width maybe some between idle and half throttle....to be honest you have not even seen the spray pattern yet.... it's far to fast for the human eye to see.... that is why i asked to illuminate the spray pattern with a neon light it slow's it down.... very similar to a strobe light. I will say it again any injector that is rated at 80/90 lbs at 13 psi is NOT the right injector that is enough fuel for a 375/400 hp 454 way to much for a 280hp 350 running at 30PSI..... the fact its running rich is perfect.
I hope im not being sharp angled here i just want to see you get that tub running what you could do is take pic's of what you are doing so he can see for his own eye's...this is tough enough as it is ive never heard or seen anyone run a TBI system with a mefi 4 it should be the same as a 3 but a 4 has more parameter's and may require different component's so take pic's and take some of the doubt out of it and lets move forward progress has been made you just dont see it flooding is the most positive result yet the damm thing's finally firing without the aid of dumping in gas.. Pic's plz and take a 45 second vid of the spray pattern with a neon light you may be amazed.
However that being said, you mentioned my map sensor readings are off based on the rpms... But they are NOT off based on vaccum. My engine vaccum increases as I open the throttle. I remember being told at one point that this is the wrong behavior? But my cam timing is good, compression is good, and I sprayed a ton of carb cleaner around the intake and had no increase in rpm that would indicate a leak.[/QUOTE]
Ok go to school a bit......... https://youtu.be/gq4szm5Re0g
The part number you are thinking about (GM part number) is 25170301. I ordered those from a fuel injection guy, but they are really hard to find. Unfortunately one was bad out of the box, and here's the thing.... I know my eye isn't a calibrated instrument, but I had one Tj 11, and the one new 25170301 side by side in the pod... I didn't see any noticeable difference in spray.
Lastly, BUP - you said my injector pulse widths are far too narrow. Since this is a function of the ECM, and not the injector, doesn't this all point back to a bad ecm again? Are there any published testing procedures or default parameters for injector pulse width? If the ecm is receiving proper readings from the map, ECT, IAT, TPS, but it's still producing the wrong pulse width, to me that sounds like a bad ecm.
However that being said, you mentioned my map sensor readings are off based on the rpms... But they are NOT off based on vaccum. My engine vaccum increases as I open the throttle. I remember being told at one point that this is the wrong behavior? But my cam timing is good, compression is good, and I sprayed a ton of carb cleaner around the intake and had no increase in rpm that would indicate a leak.[/QUOTE]
Nun i hate to interupt your train of thought here but stay with BUP he is diagnosing your entire system not just the map but the whole system they (ect,,map,,,mat) are all interelated simple but very confusing. Let him trouble shoot the system his way this can be frustrating enough by itself say less for someone taking it all over the place. Now as to your injectors there all wrong (ebay right) and no you cannot see any difference in pulse width maybe some between idle and half throttle....to be honest you have not even seen the spray pattern yet.... it's far to fast for the human eye to see.... that is why i asked to illuminate the spray pattern with a neon light it slow's it down.... very similar to a strobe light. I will say it again any injector that is rated at 80/90 lbs at 13 psi is NOT the right injector that is enough fuel for a 375/400 hp 454 way to much for a 280hp 350 running at 30PSI..... the fact its running rich is perfect.
I hope im not being sharp angled here i just want to see you get that tub running what you could do is take pic's of what you are doing so he can see for his own eye's...this is tough enough as it is ive never heard or seen anyone run a TBI system with a mefi 4 it should be the same as a 3 but a 4 has more parameter's and may require different component's so take pic's and take some of the doubt out of it and lets move forward progress has been made you just dont see it flooding is the most positive result yet the damm thing's finally firing without the aid of dumping in gas.. Pic's plz and take a 45 second vid of the spray pattern with a neon light you may be amazed.
However that being said, you mentioned my map sensor readings are off based on the rpms... But they are NOT off based on vaccum. My engine vaccum increases as I open the throttle. I remember being told at one point that this is the wrong behavior? But my cam timing is good, compression is good, and I sprayed a ton of carb cleaner around the intake and had no increase in rpm that would indicate a leak.[/QUOTE]
Ok go to school a bit......... https://youtu.be/gq4szm5Re0g
Last edited by Pliant; 05-25-2015 at 12:03 PM.