Cutting out under WOT in boost areas
i also have my doubts about those leaks being the issue but its worth the peace of mind to go over the fundamentals like you did. just another thought...how about the line from the manifold to the brake booster? does it have a good check valve.
i think the engine to frame ground is important and good to do esp with the remote mounted battery.
hope its sorted out
i think the engine to frame ground is important and good to do esp with the remote mounted battery.
hope its sorted out
Last edited by 350SS; Aug 23, 2019 at 05:29 PM.
i went back and looked at your first datalog you posted...
maybe i'm missing something but i thinkg there has to be something wrong with the wiring for your map sensor (i would think its the sensor but you replaced it already)
i'm just repeating what you said already here:
in the log the map value goes from 147kpa (~7psi) to 50kpa (~14in vacuum) in 0.39 seconds
throttle position is still at 100% and rpm only drops ~100 rpm still at ~43-4200rpm
how does a motor operating at 4300rpm with the throttle all the way open pull 14 in of vacuum?
hopefull the engine to frame ground solved this but i think it has to be something with the map wiring
maybe i'm missing something but i thinkg there has to be something wrong with the wiring for your map sensor (i would think its the sensor but you replaced it already)
i'm just repeating what you said already here:
in the log the map value goes from 147kpa (~7psi) to 50kpa (~14in vacuum) in 0.39 seconds
throttle position is still at 100% and rpm only drops ~100 rpm still at ~43-4200rpm
how does a motor operating at 4300rpm with the throttle all the way open pull 14 in of vacuum?
hopefull the engine to frame ground solved this but i think it has to be something with the map wiring
9 Second Club
Joined: Nov 2003
Posts: 13,616
Likes: 185
From: Norn Iron
i went back and looked at your first datalog you posted...
maybe i'm missing something but i thinkg there has to be something wrong with the wiring for your map sensor (i would think its the sensor but you replaced it already)
i'm just repeating what you said already here:
in the log the map value goes from 147kpa (~7psi) to 50kpa (~14in vacuum) in 0.39 seconds
throttle position is still at 100% and rpm only drops ~100 rpm still at ~43-4200rpm
how does a motor operating at 4300rpm with the throttle all the way open pull 14 in of vacuum?
hopefull the engine to frame ground solved this but i think it has to be something with the map wiring
maybe i'm missing something but i thinkg there has to be something wrong with the wiring for your map sensor (i would think its the sensor but you replaced it already)
i'm just repeating what you said already here:
in the log the map value goes from 147kpa (~7psi) to 50kpa (~14in vacuum) in 0.39 seconds
throttle position is still at 100% and rpm only drops ~100 rpm still at ~43-4200rpm
how does a motor operating at 4300rpm with the throttle all the way open pull 14 in of vacuum?
hopefull the engine to frame ground solved this but i think it has to be something with the map wiring
Thread Starter
Staging Lane
Joined: Sep 2017
Posts: 63
Likes: 1
From: Albuquerque, NM
i also have my doubts about those leaks being the issue but its worth the peace of mind to go over the fundamentals like you did. just another thought...how about the line from the manifold to the brake booster? does it have a good check valve.
i think the engine to frame ground is important and good to do esp with the remote mounted battery.
hope its sorted out
i think the engine to frame ground is important and good to do esp with the remote mounted battery.
hope its sorted out
Restricted User
Joined: Mar 2014
Posts: 7,192
Likes: 109
From: Ohio
I just seen your throttle cable. I'm not sure how you actually expect that to work out lol. Should've just bought a stock LS truck cable from the JY.
As far as MAP readings dropping to a vacuum reading while wide open throttle, no amount of boost leaks would ever do that. There's a major major issue if your MAP reading is reading vacuum while wide open.
As far as MAP readings dropping to a vacuum reading while wide open throttle, no amount of boost leaks would ever do that. There's a major major issue if your MAP reading is reading vacuum while wide open.
Thread Starter
Staging Lane
Joined: Sep 2017
Posts: 63
Likes: 1
From: Albuquerque, NM
i went back and looked at your first datalog you posted...
maybe i'm missing something but i thinkg there has to be something wrong with the wiring for your map sensor (i would think its the sensor but you replaced it already)
i'm just repeating what you said already here:
in the log the map value goes from 147kpa (~7psi) to 50kpa (~14in vacuum) in 0.39 seconds
throttle position is still at 100% and rpm only drops ~100 rpm still at ~43-4200rpm
how does a motor operating at 4300rpm with the throttle all the way open pull 14 in of vacuum?
hopefull the engine to frame ground solved this but i think it has to be something with the map wiring
maybe i'm missing something but i thinkg there has to be something wrong with the wiring for your map sensor (i would think its the sensor but you replaced it already)
i'm just repeating what you said already here:
in the log the map value goes from 147kpa (~7psi) to 50kpa (~14in vacuum) in 0.39 seconds
throttle position is still at 100% and rpm only drops ~100 rpm still at ~43-4200rpm
how does a motor operating at 4300rpm with the throttle all the way open pull 14 in of vacuum?
hopefull the engine to frame ground solved this but i think it has to be something with the map wiring
As well, I also order a baffled catch can for the truck, should be here tomorrow it has accommodations for a vent (filter) or no vent (block off). I'm assuming I should have it vented. And I would just take the line from the passenger valve cover, hook it to the tank, then line from the tank back to the throttle body?
Thanks again guys, more to come very soon!
Thread Starter
Staging Lane
Joined: Sep 2017
Posts: 63
Likes: 1
From: Albuquerque, NM
I just seen your throttle cable. I'm not sure how you actually expect that to work out lol. Should've just bought a stock LS truck cable from the JY.
As far as MAP readings dropping to a vacuum reading while wide open throttle, no amount of boost leaks would ever do that. There's a major major issue if your MAP reading is reading vacuum while wide open.
As far as MAP readings dropping to a vacuum reading while wide open throttle, no amount of boost leaks would ever do that. There's a major major issue if your MAP reading is reading vacuum while wide open.
And alright!! Definitely something up with that. I will put the majority of my efforts on checking MAP wiring and getting that ground cable from my block to frame in and see what it looks like, I will report back my findings.
Thread Starter
Staging Lane
Joined: Sep 2017
Posts: 63
Likes: 1
From: Albuquerque, NM
Hey guys got my catch can in the mail yesterday, gonna run from PCV valve to catch can then outlet back to the manifold. I will have a filter on the top for venting, and plan on running the passenger side valve cover after the filter before turbo with a check valve in line. Seems to be the setup that most guys are using on here from the few threads I've read on it. My question with that is, the check valve needs to be positioned to where it vents to the turbo under boost and shuts when the engine is under vacuum?
Got my cable made FINALLY yesterday. So I'll get that on first thing in the morning tomorrow because it's my day off. As well, I'll check out all my map wires for continuity. And then I should check the 5v wire with koeo? What should it be reading koeo? I believe before when I looked at it it was around 2.5v.
Also going to go through my PIDS and everything and absolutely make sure everything is setup correctly to read the values it should be.
Got my cable made FINALLY yesterday. So I'll get that on first thing in the morning tomorrow because it's my day off. As well, I'll check out all my map wires for continuity. And then I should check the 5v wire with koeo? What should it be reading koeo? I believe before when I looked at it it was around 2.5v.
Also going to go through my PIDS and everything and absolutely make sure everything is setup correctly to read the values it should be.
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Staging Lane
Joined: Sep 2017
Posts: 63
Likes: 1
From: Albuquerque, NM
Also! I found a thread on the hp tuners forum that showed how to get your linear and offset data using the factory PDF for the map sensor.
(MaxP-MINP)/(MaxV-MINV)
(200-20) / (4.88-0.405)
180 / 4.475
40.2234636872 KPA per Volt
X 5Volts
201.1173184358 per 5 volts (linear)
Offset: 200 - [201.1173184358 × (4.88/5)]
200 - [201.1173184358 × .976]
200 - 196.2905027933
3.7094972067 offset
Gonna check the map wires first and get that ground installed and see how that goes before I try anything else with these map values. But thought it was interesting that I came up with different numbers than the 200kpa linear and 8.0kpa offset.
(MaxP-MINP)/(MaxV-MINV)
(200-20) / (4.88-0.405)
180 / 4.475
40.2234636872 KPA per Volt
X 5Volts
201.1173184358 per 5 volts (linear)
Offset: 200 - [201.1173184358 × (4.88/5)]
200 - [201.1173184358 × .976]
200 - 196.2905027933
3.7094972067 offset
Gonna check the map wires first and get that ground installed and see how that goes before I try anything else with these map values. But thought it was interesting that I came up with different numbers than the 200kpa linear and 8.0kpa offset.
Thread Starter
Staging Lane
Joined: Sep 2017
Posts: 63
Likes: 1
From: Albuquerque, NM
Today is finally the day, gonna install my block to frame ground, get my pipe back in, install catch can and see how she goes. Gonna check my map wiring and check out my brake booster check valve. Wish me luck!
Thread Starter
Staging Lane
Joined: Sep 2017
Posts: 63
Likes: 1
From: Albuquerque, NM
Alright, quick update:
MAP wires checked out fine in their continuity test and I had 5v at the 5v reference wire. Put charge pipe back in, and hooked up frame to engine block ground. Check valve tested out okay on booster. Seemed to not cut out as badly. Ground portion I attached to frame seemed a little dirty so I'll clean that first thing in the morning and try it out again but it seemed to work a lot better. Recalibrated my wideband and my values in my VE didn't change too much. I did notice however more knock than before. I started a run and got almost 7 degrees pulled out total!! Yikes! But only ended up showing 3 removed from knock retard. But I applied those values to my table to take them out. When it did cut out today it did so around 5200 rpm instead of right when boost hit. I thi k the cleaner grou d connection and install my catch can and see what she does, but even just idling and cruising around it seemed quieter, throttle response was better. All around better everywhere! I'll keep the updates coming.
MAP wires checked out fine in their continuity test and I had 5v at the 5v reference wire. Put charge pipe back in, and hooked up frame to engine block ground. Check valve tested out okay on booster. Seemed to not cut out as badly. Ground portion I attached to frame seemed a little dirty so I'll clean that first thing in the morning and try it out again but it seemed to work a lot better. Recalibrated my wideband and my values in my VE didn't change too much. I did notice however more knock than before. I started a run and got almost 7 degrees pulled out total!! Yikes! But only ended up showing 3 removed from knock retard. But I applied those values to my table to take them out. When it did cut out today it did so around 5200 rpm instead of right when boost hit. I thi k the cleaner grou d connection and install my catch can and see what she does, but even just idling and cruising around it seemed quieter, throttle response was better. All around better everywhere! I'll keep the updates coming.
I think your map sensor is hooked up backwards.
Duty cycle of 35% at 7psi on 60lbs injectors is definitely off. It should be higher than that. I suspect you are running lean as **** when it cuts out.
It could also lie in your tune file. You need to find out what settings affect fueling at 100% throttle. Do a compare of a past working time if you have one. One that worked under boost.
What is is your timing at 7psi of boost and what fuel are you using? If you are at 17 degrees or under at 7psi on pump and it’s knock retarding 7 degrees, that’s again pointing to lean.
Are you 100% sure you have fuel pressure when it noses over? It could be losing pressure inside the tank at your hose on the fuel pump.
What is your fuel fuel level at? Do you have at least half a tank of fuel? Mine would do this below half a tank until I upgraded the fuel pump bucket, which on my vehicle does not hold a lot of fuel.
Duty cycle of 35% at 7psi on 60lbs injectors is definitely off. It should be higher than that. I suspect you are running lean as **** when it cuts out.
It could also lie in your tune file. You need to find out what settings affect fueling at 100% throttle. Do a compare of a past working time if you have one. One that worked under boost.
What is is your timing at 7psi of boost and what fuel are you using? If you are at 17 degrees or under at 7psi on pump and it’s knock retarding 7 degrees, that’s again pointing to lean.
Are you 100% sure you have fuel pressure when it noses over? It could be losing pressure inside the tank at your hose on the fuel pump.
What is your fuel fuel level at? Do you have at least half a tank of fuel? Mine would do this below half a tank until I upgraded the fuel pump bucket, which on my vehicle does not hold a lot of fuel.
So then.... After making the according changes to my tune based on the two logs I just posted, I cruised around for a few to let everything circulate and cycle etc. Then I did two more logs (one cruise and one WOT) and got almost the exact opposite readings as what I did before. Using a Innovate LC-2 using HP Tuners presets for logging. But even this lean.. and its still falling on its face. Now I did notice during the last two logs that my gas level had gone below a 1/4 tank, but I wouldnt see that being too much of an issue? Havent made any more changes since the first itteration this morning, but here is those two files I did last and Ill go ahead and post the tune again for you all to look at, thanks!
Fuel level could absolutely be the culprit
Thread Starter
Staging Lane
Joined: Sep 2017
Posts: 63
Likes: 1
From: Albuquerque, NM
I think your map sensor is hooked up backwards.
Duty cycle of 35% at 7psi on 60lbs injectors is definitely off. It should be higher than that. I suspect you are running lean as **** when it cuts out.
It could also lie in your tune file. You need to find out what settings affect fueling at 100% throttle. Do a compare of a past working time if you have one. One that worked under boost.
What is is your timing at 7psi of boost and what fuel are you using? If you are at 17 degrees or under at 7psi on pump and it’s knock retarding 7 degrees, that’s again pointing to lean.
Are you 100% sure you have fuel pressure when it noses over? It could be losing pressure inside the tank at your hose on the fuel pump.
What is your fuel fuel level at? Do you have at least half a tank of fuel? Mine would do this below half a tank until I upgraded the fuel pump bucket, which on my vehicle does not hold a lot of fuel.
Duty cycle of 35% at 7psi on 60lbs injectors is definitely off. It should be higher than that. I suspect you are running lean as **** when it cuts out.
It could also lie in your tune file. You need to find out what settings affect fueling at 100% throttle. Do a compare of a past working time if you have one. One that worked under boost.
What is is your timing at 7psi of boost and what fuel are you using? If you are at 17 degrees or under at 7psi on pump and it’s knock retarding 7 degrees, that’s again pointing to lean.
Are you 100% sure you have fuel pressure when it noses over? It could be losing pressure inside the tank at your hose on the fuel pump.
What is your fuel fuel level at? Do you have at least half a tank of fuel? Mine would do this below half a tank until I upgraded the fuel pump bucket, which on my vehicle does not hold a lot of fuel.
According to my Wideband O2 sensor I'm not too far off my commanded air fuel when it cuts out. I'll look through my tune again and see if there is anything that affects wide open throttle fueling.
Timing where the knock occurred was around ten degrees, and took it down to 2.5 degrees. I was not under boost yet it was around 80 kpa. It was right after I rolled into WOT. And my wideband O2 said it was 2% lean. Under full boost it was knocking from 1.8 degrees up to 6 degrees. And again reading about 2% lean to 1% rich. And I can check the pump hose tomorrow where it connects to the sender. But on my mechanical guage hooked to the rail it never drops below 55-50psi.
I do have at least a half tank in the truck at all times now and reading back through your post about the duty cycle.. I inputted all the data that the injector company gave me when I installed the injectors. They are advertised as 60lb injectors but in my injector table they told me to put them at 72.3lbs because of the pressure difference from my pump to what they tested them at. If you find anything that looks off in the "new" tune I posted let me know
Last edited by Soupermn; Aug 28, 2019 at 08:43 PM.
According to my map sensor connector and the pinouts for my 99-02 PCM it is all hooked up correctly.
According to my Wideband O2 sensor I'm not too far off my commanded air fuel when it cuts out. I'll look through my tune again and see if there is anything that affects wide open throttle fueling.
Timing where the knock occurred was around ten degrees, and took it down to 2.5 degrees. I was not under boost yet it was around 80 kpa. It was right after I rolled into WOT. And my wideband O2 said it was 2% lean. Under full boost it was knocking from 1.8 degrees up to 6 degrees. And again reading about 2% lean to 1% rich. And I can check the pump hose tomorrow where it connects to the sender. But on my mechanical guage hooked to the rail it never drops below 55-50psi.
I do have at least a half tank in the truck at all times now
According to my Wideband O2 sensor I'm not too far off my commanded air fuel when it cuts out. I'll look through my tune again and see if there is anything that affects wide open throttle fueling.
Timing where the knock occurred was around ten degrees, and took it down to 2.5 degrees. I was not under boost yet it was around 80 kpa. It was right after I rolled into WOT. And my wideband O2 said it was 2% lean. Under full boost it was knocking from 1.8 degrees up to 6 degrees. And again reading about 2% lean to 1% rich. And I can check the pump hose tomorrow where it connects to the sender. But on my mechanical guage hooked to the rail it never drops below 55-50psi.
I do have at least a half tank in the truck at all times now
Well damn. I’ll try and look at your tune file later this evening.
Are you sure you're not getting false knock and youre not having it break up because the timing is in the dirt? If you richen it or pull timing and it's still knocking then it's probably fake and the main cause of your car breaking up.
Thread Starter
Staging Lane
Joined: Sep 2017
Posts: 63
Likes: 1
From: Albuquerque, NM
And I noticed in my datalog that the MAP value did drop again as before but not as bad, I could feel it in the truck, but it didn't fall on its face like it was doing. so it has improved with what members here have posted up for me to try. "New" tune below. I see what you are saying about the duty cycle. They 60lb injectors, but in my injector table they are 72.3lbs, that's what the company sent me for the info for them because my pump is rated at a higher pressure than what they test their injectors at. If anything looks off in this new tune let me know
Last edited by Soupermn; Aug 28, 2019 at 08:45 PM.
Thread Starter
Staging Lane
Joined: Sep 2017
Posts: 63
Likes: 1
From: Albuquerque, NM
Good thing to point out!!! I shall experiment with this tomorrow!
Thread Starter
Staging Lane
Joined: Sep 2017
Posts: 63
Likes: 1
From: Albuquerque, NM
So, I cleaned my grounds. And installed my catch can today. It goes from PCV valve to can, then can to intake with check valve in between. Passenger valve cover is hooked to the intake pipe before the turbo. No more boost cut, no more oil leaky rear main seal, no more oil cap blowing off, everything is perfect!! Had to re enable Traction control. It's pointless driving the truck without it. It pulls so hard!! I will post tune and recent logs later. Thanks everyone so much!