What are you using for gauges, electronic or analog? Start at the begining, verify you have good pressure to the CP-3 and check your rail pressure to make sure it is not bottoming out.
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Lack of power in '03 w/HE351, smarty jr,
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Ultra gauge on order. Let's see how long it'll take to get up here.
What's the best way to set up a fuel pressure gauge?(lift pump pressure)
When I first installed HE351 I didn't adjust wastegate. It would only do 22psi and egt was high instantly. I shortened sdjustment rod a fair bit and it went to 26 psi (stock pressure on 03). Since I should have been seeing 36-37 psi Harry at peak diesel suggested a pair of vise grips on hose to wastegate actuator. After that I had 35 psi +. I tried an adjustable boost elbow and an elbow from an Edge Ez but it was either 26 psi or 35+. I just left the vise grips in place. I knew my drive pressure would be high under full power but that only happens briefly when passing or up hill towing. (Our hills aren't that big or long on the prairies).
Boost fooler didnt change anything.
Side note, I just put an M085171 muffler on my '05. The flo-pro exhaust was way too loud. It was a perfect fit. The Donaldson was the same length as their "muffler" and one small piece of pipe. I welded on a bracket on the muffler and extended the tailpipe past my mudflap. Hopefully I can hear myself think. Thanks again. TDR is a much better forum for actual help.
What's the best way to set up a fuel pressure gauge?(lift pump pressure)
When I first installed HE351 I didn't adjust wastegate. It would only do 22psi and egt was high instantly. I shortened sdjustment rod a fair bit and it went to 26 psi (stock pressure on 03). Since I should have been seeing 36-37 psi Harry at peak diesel suggested a pair of vise grips on hose to wastegate actuator. After that I had 35 psi +. I tried an adjustable boost elbow and an elbow from an Edge Ez but it was either 26 psi or 35+. I just left the vise grips in place. I knew my drive pressure would be high under full power but that only happens briefly when passing or up hill towing. (Our hills aren't that big or long on the prairies).
Boost fooler didnt change anything.
Side note, I just put an M085171 muffler on my '05. The flo-pro exhaust was way too loud. It was a perfect fit. The Donaldson was the same length as their "muffler" and one small piece of pipe. I welded on a bracket on the muffler and extended the tailpipe past my mudflap. Hopefully I can hear myself think. Thanks again. TDR is a much better forum for actual help.
AH64ID
TDR MEMBER
36-37 is a bit much for the HE351, as its on the very edge of what the compressor can handle (at sea level) and well beyond what the turbine can push.
Your best best for wastegate control would be a spring gate that is common on HE351's these days, as its opened by drive pressure.
Your best best for wastegate control would be a spring gate that is common on HE351's these days, as its opened by drive pressure.
Found spring gates for sale $250! That sure seems like a lot. I bought the turbo for $300 and sold my 341 for $250. I'd be better off spending that money on upgrading to a better turbo. Any suggestions for a flatlander like myself to upgrade my turbo? Towing and fuel economy being the main considerations. John your dad has a modded 351 on his truck and you have your Garrett. Would going the modded 351 work for me?
Not worth the price, you can control boost well enough with your right foot so it is a waste. The stock WG rod setting and a boost fooler cranked down with the bleed port towards the actuator nets me a constant 37-38 psi if go WOT. 99% of your driving is not going to be in those ranges so I would not even worry about 37-38 psi on the rare occasion you need it. If you roll out of the throttle at high boost instead of just dumping the throttle it is a lot easier on the turbo.
Unless you have broken the spring in the actuator you likely have problems other than the turbo. With the boost reference hose you should be able to see 40 psi with 325 HP tune and EGT's still 1300 or under. If you can't get boost over 26 psi and the EGT's stay at or under 1200 you have a fueling problem somewhere that a turbo won't fix.
Unless you have broken the spring in the actuator you likely have problems other than the turbo. With the boost reference hose you should be able to see 40 psi with 325 HP tune and EGT's still 1300 or under. If you can't get boost over 26 psi and the EGT's stay at or under 1200 you have a fueling problem somewhere that a turbo won't fix.
AH64ID
TDR MEMBER
Crazy Carl has one for $99, and I seem to remember there being some around $80 but it's been a few years.
The modded HE351 would probably be the best route, based on what I have learned about you around here, but like cerb said I don't think you have a turbo/air problem.
Personally I'd rather a truck limit itself to a safe level when passing/towing up a grade vs having to use the right foot.. but I know a LOT of people that have more fuel than turbo, or more wastegate than compressor map or turbine and just use their right foot... to me that's not a well matched motor.
The modded HE351 would probably be the best route, based on what I have learned about you around here, but like cerb said I don't think you have a turbo/air problem.
Personally I'd rather a truck limit itself to a safe level when passing/towing up a grade vs having to use the right foot.. but I know a LOT of people that have more fuel than turbo, or more wastegate than compressor map or turbine and just use their right foot... to me that's not a well matched motor.
Crazy Carl has them for $99 then when you select HE351 you add another $140. For a total of $239. It would be nice to have boost pressure limited to a certain level for sure. That way if someone else were to drive my truck I wouldn't have to worry. With it being 0F out and no heated building to work in I might not get to the bottom of things. My fuel pressure should be 20 psi at idle and 6 psi at WOT? I can use my fuel gauge for p7100 pumps tapped into FASS I would think. Rail Pressure gauges aren't cheap. I'm not sure if ultra gauge will measure it or even an Edge CTS on an 03 will work either.
Based on all th eproblems with these pumps and ULSD fuel, measuring pressure at the pump is a bad idea. You need to know what you have constantly at the inlet of the CP-3 or you are still guessing.
Rail pressure gauges are not cheap, but for troubleshooting they are priceless. If you are using the data bus to read RP you are not getting a true reading. Anything on the data bus is an interpolated value based on the ECU's view of the world. If it is scrambled you will chase problems with no solutions.
Electronic gauges are great when everything works, useless when there is an electronic issue. Not as if this is not a distinct possibility. Get analog gauges if you want consistency and accuracy.
Rail pressure gauges are not cheap, but for troubleshooting they are priceless. If you are using the data bus to read RP you are not getting a true reading. Anything on the data bus is an interpolated value based on the ECU's view of the world. If it is scrambled you will chase problems with no solutions.
Electronic gauges are great when everything works, useless when there is an electronic issue. Not as if this is not a distinct possibility. Get analog gauges if you want consistency and accuracy.
I think you have that backwards, the ECU is using the data bus to send the info not accept it. What you read from the OBD port has been affected by the ECU interpeting the signal from the sensors. AFAIK, the only sensors that are truly digital are the cam and crank sensor, and even that is subject to calculation to determine rpm's.
There is an infinite number of readings that can exist an any voltage range so it has to be interpolated from a table to convert to usable values. That is only half the problem, any sensor can be off as read by the ECU if there is a corroded battery cable, power cable, a bad battery, or a bad connection on any number of harness connections.
Some analog gauges ar enore accurate thna others. Don't exect a Glo-Shift to be as accurate as an EV II, the more you pay the better the accuracy is unless you get a bad gauge. Trying one gauge and deeming the gauge bad does neccessarily make it bad.
Comparing to the what the ECU puts on the bus may not be accurate, or, the gauge may not be accurate. There is no way to absolutely know for sure so it is a guess which one is correct.
There is an infinite number of readings that can exist an any voltage range so it has to be interpolated from a table to convert to usable values. That is only half the problem, any sensor can be off as read by the ECU if there is a corroded battery cable, power cable, a bad battery, or a bad connection on any number of harness connections.
Some analog gauges ar enore accurate thna others. Don't exect a Glo-Shift to be as accurate as an EV II, the more you pay the better the accuracy is unless you get a bad gauge. Trying one gauge and deeming the gauge bad does neccessarily make it bad.
Comparing to the what the ECU puts on the bus may not be accurate, or, the gauge may not be accurate. There is no way to absolutely know for sure so it is a guess which one is correct.
AH64ID
TDR MEMBER
The ECM has to interpret those signals prior to using them, making them more accurate to what the ECM is doing. The ECM needs to knowers sure to determine injector open time, it uses the signal from the rail pressure sensor to determine pressure and then look at the tables.
The data available via the OBDII port or 4 pin port is what the ECM is using for rail pressure and CP3 and injector commands, to me that is the most accurate. If it isn't exactly what the pressure is then it doesn't matter, as its what the ECM thinks it is and unless you are using a rail pressure module that's the number you want to know.
From a tuning standpoint the OBDII data is the way to go, and an external gauge is only needed if your RP cannot be read via OBDII or you run a pressure box.
My understanding of what the ECM does is based on what I know exists inside the ECM. The ECM rail pressure table uses pressure in MPa, and has a voltage to MPa table for taking the rail pressure signal and making it into pressure.
The data available via the OBDII port or 4 pin port is what the ECM is using for rail pressure and CP3 and injector commands, to me that is the most accurate. If it isn't exactly what the pressure is then it doesn't matter, as its what the ECM thinks it is and unless you are using a rail pressure module that's the number you want to know.
From a tuning standpoint the OBDII data is the way to go, and an external gauge is only needed if your RP cannot be read via OBDII or you run a pressure box.
My understanding of what the ECM does is based on what I know exists inside the ECM. The ECM rail pressure table uses pressure in MPa, and has a voltage to MPa table for taking the rail pressure signal and making it into pressure.
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That is exactly my point, the ECU interpolates the signal to get a value it can use, doesn't really matter if it is using MPa or PSI or F or C what matters is a voltage signal is converted to a discreet value. That discreet value is then used to detemine operations AND put on the data bus.
The problem is EVERY connection in the harness becomes a failure point. EVERY remote signal, both read and transmitted, can be degraded by connections and the wiring harness itself resulting in invalid information. The engineers expected this and deisgned into the interpolation logic algorithms that define a range\time combination a signal from\to a sensor\relay\solenoid can have. This "smoothing" of the actual signal is exactly the difference between an analog and the electronic gauge. What you GET from the OBD port may not be what actually IS going on.
This happens constantly, with no CEL's, that results in degraded performance. Fan codes, MAP readings not consistent, battery temps not consistent, gov solenoids and transdcuers not correct based on analog readings, FCA operation that creates perfomance issues. As these trucks age the degradation of the harness and componeent siwll be the single largest problem, and frequently there is no way to tell what the problem is.
Given 1 truck and 1 gauge how can you KNOW what is the correct reading? Anser is you one cannot knwo for sure. All we can do is compare actual readings to what has been published as the stnadard and make a decision based on that. Given 100 psi variation at idle between a EV II and the ECU as read thru the OBD port, we still don't KNOW which ones is correct we guess based on what we assume is a correct standard. Peirodically, that will come back and bite us, guarnateed.
Been there, done that.
You are correct in stating the electronic values should be correct, all things being equal. The inequalities which cause all the problems are where things start to diverge. The OP's case looks to be one of those where for no reason readings are not up to standard. Since he hasn't answered how he is reading boost it is imposssible to tell if boost is really low or just invalid. The fact the EGT's are lower indicates something in the electronics is not correct. Plugging another electronic reader into a vehicle with suspected electronic issues does not generate confidence.
The problem is EVERY connection in the harness becomes a failure point. EVERY remote signal, both read and transmitted, can be degraded by connections and the wiring harness itself resulting in invalid information. The engineers expected this and deisgned into the interpolation logic algorithms that define a range\time combination a signal from\to a sensor\relay\solenoid can have. This "smoothing" of the actual signal is exactly the difference between an analog and the electronic gauge. What you GET from the OBD port may not be what actually IS going on.
This happens constantly, with no CEL's, that results in degraded performance. Fan codes, MAP readings not consistent, battery temps not consistent, gov solenoids and transdcuers not correct based on analog readings, FCA operation that creates perfomance issues. As these trucks age the degradation of the harness and componeent siwll be the single largest problem, and frequently there is no way to tell what the problem is.
Given 1 truck and 1 gauge how can you KNOW what is the correct reading? Anser is you one cannot knwo for sure. All we can do is compare actual readings to what has been published as the stnadard and make a decision based on that. Given 100 psi variation at idle between a EV II and the ECU as read thru the OBD port, we still don't KNOW which ones is correct we guess based on what we assume is a correct standard. Peirodically, that will come back and bite us, guarnateed.
Been there, done that.You are correct in stating the electronic values should be correct, all things being equal. The inequalities which cause all the problems are where things start to diverge. The OP's case looks to be one of those where for no reason readings are not up to standard. Since he hasn't answered how he is reading boost it is imposssible to tell if boost is really low or just invalid. The fact the EGT's are lower indicates something in the electronics is not correct. Plugging another electronic reader into a vehicle with suspected electronic issues does not generate confidence.
AH64ID
TDR MEMBER
The external gauge I used has far more "smoothing" than the OBDII port, one appears to be real time while the other appears to be an average.
I haven't used an ISSPRO EV2 RP gauge but I have the tuning program which has the defaults, and it too will have more "smoothing" than the OBDII readers I have used.
From a tuning standpoint the ECU is the accurate one, from actually knowing the pressure in the rail?? Well that's the million dollar question, especially since they both use the same sender.
Both EV2 and OBDII are interpreted signals, so nothing is "analog".
I haven't used an ISSPRO EV2 RP gauge but I have the tuning program which has the defaults, and it too will have more "smoothing" than the OBDII readers I have used.
From a tuning standpoint the ECU is the accurate one, from actually knowing the pressure in the rail?? Well that's the million dollar question, especially since they both use the same sender.
Both EV2 and OBDII are interpreted signals, so nothing is "analog".
The EVII can be adjusted for sensitivity and mine is pretty close to what the ECU is reporting on variation, when everything works right. The gauge has its own algorithms for determing values that is separate form the ECU.
I have also seen the demanded bouncing between 21k and 23k and the gauge maxxed quivering at 26k or so with electrical problems evident.
The gauages are reading directly from the sensor, the OBD port is reading what is on the bus thru 5-6 feet of harness after the ECU reads, smooths, and interprets the signal thru 3-4 ft of harness that is subject to degradation and electrical noise. Both will go whacko with a dirty power signal, the ECU will have a lot more variance if the ground side or other component goes bad.
The simple fact you can unhook the batteries and periodically fix weird electrical issues is pretty definitive the ECU source and data bus are not always to be trusted.
I have also seen the demanded bouncing between 21k and 23k and the gauge maxxed quivering at 26k or so with electrical problems evident.
The gauages are reading directly from the sensor, the OBD port is reading what is on the bus thru 5-6 feet of harness after the ECU reads, smooths, and interprets the signal thru 3-4 ft of harness that is subject to degradation and electrical noise. Both will go whacko with a dirty power signal, the ECU will have a lot more variance if the ground side or other component goes bad.
The simple fact you can unhook the batteries and periodically fix weird electrical issues is pretty definitive the ECU source and data bus are not always to be trusted.
AH64ID
TDR MEMBER
Yeah I rather like the EV2's for that reason. It's nice to slow down the readings on oil and fuel pressure but keep boost and EGT's as fast as possible.
What are you using to read demanded? What elevation and temp were you at?
Some of the Smarty tunes will run the demanded rail pressure up when the IAT's and elevation are high. My demanded will go to 26,107 with IAT's above 75° and 8,000',.. Marco is aware.
Yeah signals can go whacky, but should be symptoms of it to follow.
I guess I haven't ran across any odd electrical issues on my truck, I know it's only one sample but...
What are you using to read demanded? What elevation and temp were you at?
Some of the Smarty tunes will run the demanded rail pressure up when the IAT's and elevation are high. My demanded will go to 26,107 with IAT's above 75° and 8,000',.. Marco is aware.
Yeah signals can go whacky, but should be symptoms of it to follow.
I guess I haven't ran across any odd electrical issues on my truck, I know it's only one sample but...
Using the AutoEnginuity to read and log. I had unloaded the Smarty trying to figure out what the devil was wrong with the truck.
When these trucks get an electircal gremlin they are really a hair pulling event. I have had a couple issues with bad connections and a possible bad battery that sent it into the twilight zone.
When the issues with pressures happened it was cold and at 700 ft elevation. Started the truck with ambient in the 60's, it idled for a couple minutes then went beserk. Charging quit, rail pressure maxxed out, idle went to about 1100 rpms and rattled like crazy. Every single engine parameter sensor went to high voltage and it threw every code possible for engine operation. I was checking demanded against what the rail gauage was saying trying to figure out what was going and they were way off. The other pids for MAP and temp were all over the place maxed and then drop to nothing. Figured it either shorted the OBD harness or the ECU. Started unplugging all the components and gauges trying to figure out what the heck happened. It would periodically run for 5 minutes or so and then go back to the same condition if it didn't go to it right off start.
Never figured out for sure what the issue was but after disconnecting the batteries, discharging the ECU, and cleaning all the connections the gremlin left. About 2 months later the batteries started going low after sitting for more than a day. Only thing I could figure is a battery was starting to short out and threw garbage into the system. Never had another issue after that and replacing the batteries.
Crazy electrical monstrosities.
When these trucks get an electircal gremlin they are really a hair pulling event. I have had a couple issues with bad connections and a possible bad battery that sent it into the twilight zone.
When the issues with pressures happened it was cold and at 700 ft elevation. Started the truck with ambient in the 60's, it idled for a couple minutes then went beserk. Charging quit, rail pressure maxxed out, idle went to about 1100 rpms and rattled like crazy. Every single engine parameter sensor went to high voltage and it threw every code possible for engine operation. I was checking demanded against what the rail gauage was saying trying to figure out what was going and they were way off. The other pids for MAP and temp were all over the place maxed and then drop to nothing. Figured it either shorted the OBD harness or the ECU. Started unplugging all the components and gauges trying to figure out what the heck happened. It would periodically run for 5 minutes or so and then go back to the same condition if it didn't go to it right off start.
Never figured out for sure what the issue was but after disconnecting the batteries, discharging the ECU, and cleaning all the connections the gremlin left. About 2 months later the batteries started going low after sitting for more than a day. Only thing I could figure is a battery was starting to short out and threw garbage into the system. Never had another issue after that and replacing the batteries.
Crazy electrical monstrosities.
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Hey Chuck-
I think John called it on the lack of fuel causing your problem. I went through the same thing with mine a few months ago- noticeable loss of power and lower than normal boost out of my 351CW. Turned out to be my aftermarket lift pump failed. I didn't realize that the CP3 would draw through my aftermarket pump because it absolutely would not draw through the factory lift pump. Once I replaced the lift pump, all was good again. Might try checking the pressure relief valve on the rail, the rail pressure sensor, and the FCA.
Please let us know how you end up.
100 Proof
I think John called it on the lack of fuel causing your problem. I went through the same thing with mine a few months ago- noticeable loss of power and lower than normal boost out of my 351CW. Turned out to be my aftermarket lift pump failed. I didn't realize that the CP3 would draw through my aftermarket pump because it absolutely would not draw through the factory lift pump. Once I replaced the lift pump, all was good again. Might try checking the pressure relief valve on the rail, the rail pressure sensor, and the FCA.
Please let us know how you end up.
100 Proof
I guess its time for an update. I towed with my truck the other day. It pulled well. 2 things I think may have lead to slightly reduced power. Boost leak at intake horn and dirty fuel filter, the biggest problem was a faulty boost gauge making me think I had a big reduction in power.
I checked fuel pressure after new filters and had 18 psi no load. I'd like to get a fuel pressure sensor and a rail pressure sensor. I'm waiting on my 60psi boost gauge and my Ultragauge. We will see what happens after they are installed.
100proof your dyno numbers are pretty good. Where did you have the Smarty set at? What boost and egt did you see during the run. I'd be curious at where my truck(s) would be.
I put the 50 hp injectors and fluidampr on my 05 earlier this week. It definitely runs better. I haven't towed with it yet so I dont know how it really runs. My a/c condenser is really dinged up bad on it. I plan to get a new one for next spring. I'm thinking it reduces the airflow to my rad and intercooler.
We will have to see how the Smarty touches make out. Maybe one of those and some UDC tuning for next fall. The other thing that I might try and do would be to get a Modified HE351 to reduce the drive pressure and be hopefully a bit more efficient.
I'm not sure which clutch my 05 has but any more power in my 03 and my ConO might be pushed past its limits.
I checked fuel pressure after new filters and had 18 psi no load. I'd like to get a fuel pressure sensor and a rail pressure sensor. I'm waiting on my 60psi boost gauge and my Ultragauge. We will see what happens after they are installed.
100proof your dyno numbers are pretty good. Where did you have the Smarty set at? What boost and egt did you see during the run. I'd be curious at where my truck(s) would be.
I put the 50 hp injectors and fluidampr on my 05 earlier this week. It definitely runs better. I haven't towed with it yet so I dont know how it really runs. My a/c condenser is really dinged up bad on it. I plan to get a new one for next spring. I'm thinking it reduces the airflow to my rad and intercooler.
We will have to see how the Smarty touches make out. Maybe one of those and some UDC tuning for next fall. The other thing that I might try and do would be to get a Modified HE351 to reduce the drive pressure and be hopefully a bit more efficient.
I'm not sure which clutch my 05 has but any more power in my 03 and my ConO might be pushed past its limits.
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