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KTS-300/301 bosch hammer tool (shown) plugs into the diagnostic plug found to the right of the passenger seat
under the cover for the rear hatch release. will display fault codes, actual values, such as temps and RPM, as
well as provide a knock registration to display knock counts.
Mark's car and wiring are a kluge of different years. The original Holbert car started life as '86 ROW car, or a pre-production S4. It didn't come with the same diagnostic connectors that the later ('89+) production cars have. Mark will tell us if it has even the limited '87-88 diagnostics available. We've been pushing him to install a later engine and controller harness so a Hammer/Spanner/Theo/ST-SP will plug in. Jim Corenman has shared the needed data line connection points to add to Mark's harness to enable communications. That may be the fastest way to get access for any of the diagnostic tools. He may still have early controller ROMs, so may need an upgrade to later ('89+) to get full access.
Mark's car and wiring are a kluge of different years. The original Holbert car started life as '86 ROW car, or a pre-production S4. It didn't come with the same diagnostic connectors that the later ('89+) production cars have. Mark will tell us if it has even the limited '87-88 diagnostics available. We've been pushing him to install a later engine and controller harness so a Hammer/Spanner/Theo/ST-SP will plug in. Jim Corenman has shared the needed data line connection points to add to Mark's harness to enable communications. That may be the fastest way to get access for any of the diagnostic tools. He may still have early controller ROMs, so may need an upgrade to later ('89+) to get full access.
yes, that brings back some painful memories of my situation. its one of the reasons ive lost a little interest in the shark tune, because as simple as the wiring seems to you , its ominous to me. but, im not adverse to changing it !!
thanks
mark
yes, the connectror from the sensor into the harness was cracking but i put sealant over it and stabilized it from bending . the hall sensor wire coming out of the pulley cover plate looks good. what is a bosch hammer? a type of diagnostic device. im worried that i dont have the correct plug for any of these devices to check things. Bill ball would know. maybe its worth buying a new hall sensor. i first want to verify. there should be an easy way to do this with timing checks. compare to another S4. it seems simple enough.
But maybe you should fly up Bill, who is in AZ now.
You have the needed tools local to you. Jeff has repeatedly offered to connect to the car with the ST; even if just for basic diagnostics it's a worthwhile effort.
yes, ill try this and hopefully i can get jeff to help. i know he is busy and would be a lot of effort, but it would be great to see if i actually do have any issues .
Basics: If "fixing" the rear knock sensor didn't noticeably improve acceleration throughout the load range, you have another fault to hunt down. Both the knock sensors and the Hall sensor have shielding on the cabling all the way from the controller to the sensor. You can do basic Ohm meter checks from the controller plugs to see if any are shorted to ground (shield). If you unplug the controllers, you can test for that with a flashlight if you have to. A DMM is handier and safer though. You can provide a little DC excitation to a knock sensor, and connect the signal leads to a spectrum analyzer to see what all the mechanical rattling looks like. Or to a basic O'scope to see amplitude alone. O'scope will display the signals from the Hall sensor that go high-low-high-low as the cam turns. If you can't see these basic signals at the controllers end, you need to hunt down the problems. Sensor(s) or wiring.
no, the knock sensors didnt do anything and i would think that i should have been able to see some difference. its not that im feeling im down on power, im only pursuing this, because i might be. also wondering if those around have actually checked the timing, dynoed and other tests to see the difference of the knock sensors or halls disconnected. both knock sensors are new, so what do i check ? the shielding pin? and test that all the way to the ECUs? i can do that.... whats the best way to check with a flash light? power through with using the shield to ground and using 12volts on the flashilte? the wires from the hall sensor look good but the connector at the harness , where the injectors and the belt tensioner sensor meet, look old. could be a crack in there.. so i can check continuity through the cable to the ECU, right?
again, i think it would be great to see some values and conditions of timing change. i still have a feeling that maybe the ecu is ignoring those items, especially since the car has the power it should and the timing is in the 38-39 degrees btdc range . or maybe that test needs a load on the engine to confirm.
-----
Throughout this thread and in many related threads, you bombard your support team with your theory that if the mixture is always OK to a little rich on the WBO2 then the car is perfect. Each time someone on the support team attempts to educate you on even the most basic and maybe mundane issue, you dump a load of perhaps loosely-related internet "facts" on them in an attempt to not fix whatever it is that's actually wrong.
yes, we have had isssues and the shark tune always comes up. we found , on the dyno it to be pretty safe range , with decent power. how much im leaving on the table is another discussion . remember, rave all you want about the power gains, and just look no further than Andersons efforts with the shark tuner, and how the results were less than underwhelming? so why should i get so excited about it? the problems were not related to power, they were related to other things. in fact many of which were helped solved by discussions on the board about valve timing, etc. Im going to pull all those injectors out.. i just hate replacing things for the sake of replacing things. i like finding out root causes! but that willl ONLY address the other issue im seeing , which is the idle miss. (not full throttle issue at all)
Have you followed ---ANY--- of the guidance shared on cam timing? Have you found the vacuum leak? Have you looked? How well balanced are those exhaust port temps at idle, when you have the slight miss that you can only seem to hear at idle? Got a set of known-consistent injectors installed yet? Any basic performance effort really needs to work from a known-good baseline condition where everything is at least as good as the factory intended.
yes, went over all the vacuum lines (there are not many.btw) ive run with and without vacuum for other reasons and never had issues.(keeping fuel pressure up all the time) . in fact, that reminds me.. maybe ill pull the vacuum line again and see if that richens it up and helps with the miss anyway, yes, i have checked for leaks, and infact, i think part of the noise might have been based on some tightening of things when replacing the rear knock sensor......and as you know, i did leak down and compression tests to see if something was mechanically wrong as well as check the valve timing.. its not like ive not been busy working on this thing!!
I know that Rob logged a LOT of data on his way to getting his GTS stroker to where it is now. Jim & Sue had the benefit of dyno time on the GT engine before it went in the car, chassis dyno time after it was installed, and a bonus trip to Palm Springs and Phoenix for more tuning. Then more on the ride home. This is the guy that built the Sharkplotter add-on, so there's a real possibility that he knows what he's doing. Results still are not instant.
But maybe you should fly up Bill, who is in AZ now.
He can patiently read the thread to you.
You listen to Bill.
bill remembers what the wiring harness needs... im hoping you can look at it and know what and what not , we can check. if we can just check a few things that would be great.and maybe inventory what i need to get the diagnostics in order for further testing
yes, that brings back some painful memories of my situation. its one of the reasons ive lost a little interest in the shark tune, because as simple as the wiring seems to you , its ominous to me. but, im not adverse to changing it !!
thanks
mark
Step 1: Call Mark Anderson. Get a '89+ full-diagnostics engine harness set, including the diagnostic connection for the tools to connect to.
Step 2: Remove old Harness.
Step 3: Install '89+ full-diagnostics engine harness set, including the diagnostic connection for the tools to connect to.
Step 4: Connect the tool of choice to the connector.
------
Option: Find out what type of connector the ST/SP uses between the car connector and the tool. There's gotta be one there, as the tool has both the early and late connector options. Whatever's there, ping Jim C to get a drawing that shows EXACTLY which pin goes to which data connection on the controller wiring harness you have now. Find someone who can make those connections for you.
bill remembers what the wiring harness needs... im hoping you can look at it and know what and what not , we can check. if we can just check a few things that would be great.and maybe inventory what i need to get the diagnostics in order for further testing
that's a sweet offer, and its nice to see the great spirit that exists on this forum!
Years ago the community banded together and raised the money for Mark to get this motor under his hood. So the community as a whole would like to see the motor survive as long as possible and threads like this make a lot of us cringe.... https://rennlist.com/forums/928-foru...-100-each.html
This is where things get painful.
Mark anderson had greg brown and crew do a shark tuner for a day, and they ended up VERY close in power compared to where they started with the technique ive used.
There is more to tuning an engine, especially a race engine, than the final power output. You can have two identically built cars, with the exact same HP/TQ output and one could have a much better tune for longevity under race conditions and the other could have a "street tune" for occasional drag racing or stop light shenanigans.
Depending on the car, the build and intended purpose, the all out race car may actually have a lower output on purpose.
Just because the power output is similar, doesn't mean the tune is the same. When our local guy tunes an actual race car, it could very easily be an all day event on the dyno putting the engine through it's paces testing every variable possible on a dyno, and maybe even some live over the air tuning at the track (or on the street depending on just how street legal the car looks...)
The exact same car for the street would get a far less involved tune....while the overall output "on paper" could look the same.
One area that may be different is the temperature compensation map (coolant, intake air, ambient...some computers take into account multiples) and be set to bleed back timing and possibly increase fuel as temps rise. Where and how to setup such things comes with experience.
You're also forgetting about the deceleration portion of the map. This is much more difficult to properly dial in than the WOT area, and can be a key area where detonation can occur when you go from decel to WOT...over and over again during a race.
timing? well, that is another area with suspect gains vs risk.
This is one of those statements that really makes me cringe. Timing is far more important than air / fuel and the only reason why you've skated by for so long is the stock tune is very conservative.
Tuning air / fuel is easy, the O2 sensor gives you all the data.
Knowing how to properly set timing, especial in a race car not so easy.
Anyone who thinks the knock sensor is the equivalent to an O2 sensor for finding proper ignition timing shouldn't go anywhere near your engine. Often times, tuners will disconnect the knock sensors when tuning so they don't interfere with the tuning process, and only connected after everything is finalized. With many computers you need to disable their operation, not unplug them since that often sends the ECU into a "safe" map.
Frankly, in my opinion leave it alone unless you actually plan on ponying up the $$$ to have a bonafide tuning expert strap down and go through the computer. Someone with many, many years doing not much more than tuning race cars.
Not an engine builder who thinks they know how to tune. Not a mechanic who thinks they know their way around air/fuel maps....someone who specializes in nothing but tuning.
There are two people I trust on this level in Green Bay, there must be a plethora of such folks out in your neck of the woods. Luke and Todd are often track side monitoring their work in the real world too, making sure that tune is running as expected. Constantly checking logs, making small tweaks.....
To do this right, which is crucial for a race car, is a lot of work.
Expect the shop time for such an event to be 5-10+ hours minimum to get it done properly. Don't half *** it, that's how engines end up in tiny little pieces.
I'm budgeting no less than 10 hours with my 79 once I convert to EFI to have Luke tune it. Even then, I'll still have some tweaking to do as I drive it and get to know the new motor.
On the extreme side, Todd estimates him and Luke have close to 150 hours tuning his turbo and he's still tweaking it. They plan to get together this weekend to re-tune 1st and 2nd gear to lower the power in those gears.
I'm very grateful the list had faith in me and wanted to be a part of my racing journeys. Its not over yet and i think this next SCCA Runoffs National Championship should make everyone smile to see a 928 officially in the grid , on TV..... Also, since there is time, i would like to put some kind of banner with the names of all that contributed, or at least Rennlist ON the car. this is another thread.
as far as tuning, as much as you think i dont take care of this car, i do. i KNOW the tune is safe, that is the point. i also agree, in not TOUCHING the timing as i know it is critical. and by the way, the type of "tuning" that Mark Anderson did , i did. we got the fuel air ratios safe and went racing with stock maps. it ran great on the freeway, plugs look great, and felt great at all power settings no matter racing or cruising to the market for food......... the engine is now over 120 hours on it of pure racing, (and some 20k street miles) the Holbert engine was at over 100hours as well and 40,000miles of street use. when the block came out, you saw how clean and nice it was.
Then you mention what lengths everyone went through to optimize Marks and Joes car and incorporated as much of the dependent variables as possible, and look what happened to both of those motors. Sometimes SAFE is better than running old technology at the hairy edge , in my opinion..... one thing that i have thought of, is what if my car has been running 6 degrees retarded for all these years, maybe this is why thngs have run for so long. seriously though, i doubt it, as the 5 liter Holbert motor was tuned BY me to a level not seen by many 5 liter engines ... 335rwhp with only fuel regs, and a bunch of little things. i bolted all the stock stuff, not changing a thing on to the GREENBAY short block and thats what is running today heavily restricted but still running 420rwt and 377rwhp. no clutches are blowing up, transmission shearing, bearings burning, oil spraying, or exhaust smoking...........it runs great by any stretch and is safe and that shouldn't make you cringe it should make any 928'er that was apart of this project, smile . 10 years this next month!
so, I agree. i dont want to mess with the safe tune. the optimal tunes dont seem to have the best track record IMHO. however, i do want to fix the subtle things that are wrong, like the little miss and investigate the working order of the knock sensors. heck, what if the engine needs the 6 degrees to be safe and if i get things "working" it grenades on pump gas during the TV race. maybe its best just to run it and enjoy the race and competition. whats the best that the engine could make.????? 25 more hp... is that going to buy me anything? probably a place or two at best. im investing in something that is much more important for this race, and its TIRES!! brand new set of Michellins or Yokohama slicks!
btw. who was talking about an O2 sensor being equivalent to a knock sensor for tuning?
I would like to see what is going on with the knock sensors and see if the hall effect sensors are working. i want to remember, but cant, when bill did the test. i might reach out to him to see if he remembers, if the knock sensors were connected and the Hall sensor was as well. Im curious because i cant get the timing to back off at all by disconnecting the knock sensors. ill do some tests this weekend to check on continuity to the ECUs on the sensors. i would think that with all the knowledge here, and dyno times , there would be those that have tested on the dyno and found out the effects of those sensors on HP. im not seeing much on the "road dyno" and certainly not with timing as well for my first round of topical testing. ill get more creative and detailed in the near future.
I've done a lot of things with tuning and modifying the 928s from the 1984s to the S4s, but ive stayed with in the limits of safe things, including the building and tunning of several 5 liter engines built from 84 blocks and 85 engine parts.
so, yes, i KNOW how critical tuning is and have no intent to do things that many others that have done and failed. just too much risk, unless i sent the motor off to Todd for a tune!
Thanks for all the support and i just want to let it be known , how much I value all the advice, friendships and even the occasional rubbing the list has to offer.
Mark
Originally Posted by Hacker-Pschorr
Years ago the community banded together and raised the money for Mark to get this motor under his hood. So the community as a whole would like to see the motor survive as long as possible and threads like this make a lot of us cringe.... https://rennlist.com/forums/928-foru...-100-each.html
This is where things get painful.
There is more to tuning an engine, especially a race engine, than the final power output. You can have two identically built cars, with the exact same HP/TQ output and one could have a much better tune for longevity under race conditions and the other could have a "street tune" for occasional drag racing or stop light shenanigans.
Depending on the car, the build and intended purpose, the all out race car may actually have a lower output on purpose.
Just because the power output is similar, doesn't mean the tune is the same. When our local guy tunes an actual race car, it could very easily be an all day event on the dyno putting the engine through it's paces testing every variable possible on a dyno, and maybe even some live over the air tuning at the track (or on the street depending on just how street legal the car looks...)
The exact same car for the street would get a far less involved tune....while the overall output "on paper" could look the same.
One area that may be different is the temperature compensation map (coolant, intake air, ambient...some computers take into account multiples) and be set to bleed back timing and possibly increase fuel as temps rise. Where and how to setup such things comes with experience.
You're also forgetting about the deceleration portion of the map. This is much more difficult to properly dial in than the WOT area, and can be a key area where detonation can occur when you go from decel to WOT...over and over again during a race.
This is one of those statements that really makes me cringe. Timing is far more important than air / fuel and the only reason why you've skated by for so long is the stock tune is very conservative.
Tuning air / fuel is easy, the O2 sensor gives you all the data.
Knowing how to properly set timing, especial in a race car not so easy.
Anyone who thinks the knock sensor is the equivalent to an O2 sensor for finding proper ignition timing shouldn't go anywhere near your engine. Often times, tuners will disconnect the knock sensors when tuning so they don't interfere with the tuning process, and only connected after everything is finalized. With many computers you need to disable their operation, not unplug them since that often sends the ECU into a "safe" map.
Frankly, in my opinion leave it alone unless you actually plan on ponying up the $$$ to have a bonafide tuning expert strap down and go through the computer. Someone with many, many years doing not much more than tuning race cars.
Not an engine builder who thinks they know how to tune. Not a mechanic who thinks they know their way around air/fuel maps....someone who specializes in nothing but tuning.
There are two people I trust on this level in Green Bay, there must be a plethora of such folks out in your neck of the woods. Luke and Todd are often track side monitoring their work in the real world too, making sure that tune is running as expected. Constantly checking logs, making small tweaks.....
To do this right, which is crucial for a race car, is a lot of work.
Expect the shop time for such an event to be 5-10+ hours minimum to get it done properly. Don't half *** it, that's how engines end up in tiny little pieces.
I'm budgeting no less than 10 hours with my 79 once I convert to EFI to have Luke tune it. Even then, I'll still have some tweaking to do as I drive it and get to know the new motor.
On the extreme side, Todd estimates him and Luke have close to 150 hours tuning his turbo and he's still tweaking it. They plan to get together this weekend to re-tune 1st and 2nd gear to lower the power in those gears.
Even if you choose not to do a full Sharktune on it, at least get the sensors fixed so you have the horses you had when the engine was built. Get that ignition timing to at least the factory values. When I had the intermittent rear knock sensor fault I didn't notice the missing ponies in my normal driving. It just felt like it was breathing hotter intake air all the time. I could sure tell when they came back though. I'll guess 10-15% torque improvement. Is there anywhere at Sears Point or Laguna Seca where another 15% torque and horsepower might be handy? If you say no, just slack off the throttle cable some so you don't accidentally use the extra ponies.
Even if you choose not to do a full Sharktune on it, at least get the sensors fixed so you have the horses you had when the engine was built. Get that ignition timing to at least the factory values. When I had the intermittent rear knock sensor fault I didn't notice the missing ponies in my normal driving. It just felt like it was breathing hotter intake air all the time. I could sure tell when they came back though. I'll guess 10-15% torque improvement. Is there anywhere at Sears Point or Laguna Seca where another 15% torque and horsepower might be handy? If you say no, just slack off the throttle cable some so you don't accidentally use the extra ponies.
the knock sensors are new, but the only suspect sensor is the hall sensor. However, the connections look good but will check continuity today. im sure , if the timing is backed off, there will be some noticeable power loss. you remember when i first installed the cams and didnt feel comfortably with the initial settings, that the car ran down 15hp as well as had a weird exhaust note. (groweling vs screaming at high rpm for which i was used to ) i retarded the passenger side cam and immediately found the HP. dynoed the car after and it proved it............anyway, you make a clear point, of "getting the horses back" but there is NO loss in horses. thats what makes me think they never had been working or if they are disconnected now, that the system isnt detecting it. a quick check would to be with any stock 928 to give me a timing value at any RPM and any load so i can verify. remember, its not max HP that can cause a knock, it can be other things, so just being light on the "throttle" might not make it as safe, if the engine has NEVER seen the correct or stock timing values. (my other suspicion). however, im pretty sure bill was able to verify that all things were working fine. I just cant remember . (hall, knock, etc) i do remember, not registering any knocks on our test run down the hyway at WOT , high RPM levels. my goal is to verify this, one way or another this month! i hope you can assist me in reaching this not so lofty goal!
thanks! Mark
^^ Perfect poster-child case for arguing why not to do something. ^^
It isn't max HP that causes knock. Nobody ever suggested that. Instead of trying to prove that the system works in a manner acceptable to you, why not find out if it is working all the time by just testing to see if the sensors are being read by the controllers? On the way, open the door to reading the knock counts and which cylinders are contributing the most to those numbers. If you don't really care, why did you waste the time and money replacing just that rear sensor at all?
With the system actually working as designed, it would take timing out only on the specific cylinders that it detects knocking, and only for the short while that it detects the knocking. With it seeing a faulty sensor, it takes 6º out of EVERY cylinder whenever it's under load. You apparently can't tell by butt-dyno whether it's working as designed or not. And suggest that it doesn't really matter.
----
You pull arguments out of your butt and throw them at BASIC SUGGESTIONS THAT HAVE NOTHING TO DO WITH THE CRAP YOU THROW. I have no idea what you do in the bit of spare time you have between posts. I will share that if I had a staff engineer who spent 90+% of their professional time arguing against solutions using pseudo-facts that have nothing to do with the question, they would be seeking new opportunities elsewhere.
Can I recommend that you just close the thread, or not post to it any more? You started the thread to illustrate how under-maintained the knock protection system is in your car. How, in spite of that, you are still able to post decent mid-pack times in club racing. How, in spite of that and all the other shortcomings you afflict on the car, you still have fun racing on the cheap. That's awesome! Keep it up! In the future, don't bother asking questions about your car, since the answers too often require you to actually do something that takes more than a minute and more than a dollar. Maybe, just maybe, you'll discover one day that actually trying some of the possible fixes can be way more productive that arguing them into submission. Remember that definition of problem solving? Where you start with the easiest and least expensive solutions, and use some probability based on what you last worked on and the experiences of yourself and others to order the solutions? The key piece in that method is that you actually have to test for each possible cause. Not argue in a circle about how it can't be the cause, in spite of the knowledge education and experience that hand you a possible solution set on a silver platter.
There's a rather well educated and experienced support team here. You need to actually do your part, and report back the results of your actual solution testing on the car.
Step 1: Call Mark Anderson. Get a '89+ full-diagnostics engine harness set, including the diagnostic connection for the tools to connect to.
Step 2: Remove old Harness.
Step 3: Install '89+ full-diagnostics engine harness set, including the diagnostic connection for the tools to connect to.
Step 4: Connect the tool of choice to the connector.
------
Option: Find out what type of connector the ST/SP uses between the car connector and the tool. There's gotta be one there, as the tool has both the early and late connector options. Whatever's there, ping Jim C to get a drawing that shows EXACTLY which pin goes to which data connection on the controller wiring harness you have now. Find someone who can make those connections for you.
If I remember correctly, you've stated the car has dyno'd almost exactly the same over the years since putting it together after its arrival from Green Bay.
That implies that the electronic/electrical state of the car has not changed since assembly.
I will go WAY out on a limb and assume you used known good-working sensors everywhere.
Therefore, according to your dyno sheets, all your sensors are in the same state as initial assembly, frayed knock sensor wire and all.
However, it could have happened that the engine went together with a bad hall sensor, and why the engine continues to dyno the same, since 6 degrees has always been pulled from the engine. If that's the case, when replaced, you should get a bump in horsepower, using the factory tune.
So do what you have to do to get a diagnostic tool on the engine, or simply replace all the sensors.
However, it could have happened that the engine went together with a bad hall sensor,
if the hall sensor is not bad, then I would really check the wiring which OP mentioned has been taped up. this is a shielded
type cable and I know first hand, from having to cut this cable back and repair/replace a good section of it. in fact, I had to rework
that cable a few times, before I eliminated the short to ground fault code. huge difference when I finally got it right.
08-28-2018, 07:50 PM
anyway, yes, i have checked for leaks, and infact, i think part of the noise might have been based on some tightening of things when replacing the rear knock sensor......and as you know, i did leak down and compression tests to see if something was mechanically wrong as well as check the valve timing.. its not like ive not been busy working on this thing!!
seriously though, i doubt it, as the 5 liter Holbert motor was tuned BY me to a level not seen by many 5 liter engines ... 335rwhp with only fuel regs, and a bunch of little things. i bolted all the stock stuff, not changing a thing on to the GREENBAY short block and thats what is running today heavily restricted but still running 420rwt and 377rwhp. no clutches are blowing up, transmission shearing, bearings burning, oil spraying, or exhaust smoking...........it runs great by any stretch and is safe and that shouldn't make you cringe it should make any 928'er that was apart of this project, smile . 10 years this next month!