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Thread: help...Blew 2 engines this year.

  1. #1
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    help...Blew 2 engines this year.

    so i'm new to tuning. I'm a relatively smart guy and think I have a fairly good understanding on how most of it works but i'm far from an expert so asking others to look over this and tell me if i'm missing something. I will try to keep it short(but probably will get long).

    so we bought a car that was already built and supposed to have been tuned by a shop. 2000 camaro 6.0l, cxracing 76/75 turbo, 317 heads, ls9 gaskets, comp 277lr cam, built 4l60, deka 80's, etc. well it ran like crap and after a lot of work fixing their cobble job, and us putting in a wide-band and doing a bunch of tuning we finally got it going good as we thought. before putting in the wideband after a bit of fixing, driving, fixing, driving, etc all of a sudden had no oil pressure. turns out oil was full of fuel. oil change and had pressure again. got wideband and anything over idle the afr dropped and pegged at 10. so pulled a bunch of fuel from VE table and I worked on the tune from there. street tuning we got it to where we felt it was pretty dialed in and took it to the track. first pass with the crappy stall they had in it(1600 it would push through the brakes) it gave a 2.0 60' then boost came in and away it went. shifted 2nd and blew the tires off and hit the rev limiter. after regaining traction car was flying again and into 3rd. when it hit the 1000' the engine grenaded. 4 broke pistons, 2 broke rods, holes in block and pan, etc...it was impressive. so we figured with everything we had to do to it just to get it to run right and the fuel washing the oil that the engine was hurt when we got the car and moved on to replacing it. amazingly with all of that it still ran a 11.8@113

    2nd engine is a 03 5.3 that got honed, new rings gapped to .025, new bearings, btr stage 2 turbo cam, springs and all new valves, didn't port but cleaned up the 862 heads a little, etc. also put in a 4l80 and a circle d 3000rpm stall(man I love that thing). cranked and it fired on the first crank and ran great. actually got a new afr guage and sensor also. did some street tuning and back to the track last friday. our big problem was traction with it being low 50's outside. car has worn 255 mickey thompson E/T SS tires. so it would start spinning at the top of first then shift 2nd and rpm never dropped they actually shot up and hit rev limiter(6500)...peddle it etc. the 4l80 segment that was swapped in I never changed and figured I would adjust at the track so shift pints were set low(5000 rpm) I believe it to be a stock 2500 truck trans segment. after some passes I changed 2-3, and 3-4 to 5500. did a couple short runs trying to get it to launch and such...no luck and no traction(we know how to fix that so not my question). eventually started running it to the end...best was a [email protected] back halved like a beast! after 2 partial passes and 3 full passes we now had no oil pressure on this engine and oil smells like fuel. push it in the trailer. next day change oil and we have perfect pressure again but not running or sounding right. diagnosing we found cylinder 7 not firing and plug side electrode pushed down to the center electrode(so 0 gap). compression test showed 0psi so basically blew another engine after 5 passes.

    yes we know we have trans tuning to do and traction to fix so don't need help with that...slicks are on the way and new engine has been purchase(going to be stock 150k 5.3 this time...not even opening it) and in process of being swapped. my ultimate question is can someone look over our tune and scan and tell me if there is something I am missing and why do we keep washing the engine with fuel. I don't want to keep blowing them up.
    Attached Files Attached Files
    Donny O.
    99 Hugger Orange SS convertible...mostly stock
    2000 Z28...not even close to stock. LQ4/turbo

  2. #2
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    you said its a 5.3. under general in the tune its listed as a 6.0.
    your boost enrichment doesn't look like a valid number(0-32) yours is 64
    its commanding an 11.9 is that what your seeing on wideband. seems lean for 14lbs. 15*

  3. #3
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    it is currently a 5.3. was originaly a 6.0 but yes tune still says 6.0. I did not change that or the cylinder volume as I was under the impression in SD mode none of that mattered. as for the 64 in boost enrichment I have never touched it. most of the tune is unchanged since we got the car. I have been adjusting the VE table with the scanner histogram table to get it to match what it is showing me it is calling for. i'm assuming you cant see the wideband readings that I can but yes I have gotten the AFR fairly close to commanded. waste gate is 10# and that is what we are running....haven't bothered or had it hold together long enough to go higher yet. also 15 timing was what it was set at. have seen knock so didn't bother going up. again haven't had it run right or hold together long enough to do more.
    Donny O.
    99 Hugger Orange SS convertible...mostly stock
    2000 Z28...not even close to stock. LQ4/turbo

  4. #4
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    at time 5:58.6 bank 1 injector pulse width drops and goes to a 14.4 air fuel under boost.
    also your rpm limits are backwards for resume and cutoff. my best guess is thats why it cuts out. and a 500 rpm spread is horrendous.
    i see its less in gear but the prndl select is none.

  5. #5
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    I assumed that was because it blew the tires off and was on the limiter and shut the fuel off. as for the RPM limits I see what your saying and an easy fix. as for the prndl I saw that but assumed the original tuner did that for a reason and left it.....I don't know the reason so cant speak to that as it was all before we got the car.
    Donny O.
    99 Hugger Orange SS convertible...mostly stock
    2000 Z28...not even close to stock. LQ4/turbo

  6. #6
    Senior Tuner SultanHassanMasTuning's Avatar
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    Rays 2000 camaro 5.3 gld final 100419 fix.hpt

    for fueling i would use as attached, hope your using a knock box or something for ignition map
    Follow @MASTUNING visit www.mastuned.com
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  7. #7
    Tuning Addict 5FDP's Avatar
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    Also remember that early GEN 3 engines have connecting rods that will only want to handle around 500whp before they get really weak and snap. You need a later GEN 3 engine with the newer GEN 4 rods if you want to push it because those are known to take 800-1000hp. Those are generally found in 2004.5+ engines, they also call them H beam rods and the earlier ones I beams.
    2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.

    If you don't post your tune and logs when you have questions you aren't helping yourself.

  8. #8
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    Quote Originally Posted by SultanHassanMasTuning View Post
    Rays 2000 camaro 5.3 gld final 100419 fix.hpt

    for fueling i would use as attached, hope your using a knock box or something for ignition map
    I see what you did as far as enabling the boost enrichment ratio and such. that will require me to do a bunch of tweaking with the VE table I assume....and i'm fine with that. is there a reason the original tuner might have set it up the way it was? is there a reason this is a better way to do it? as a disclaimer Im not asking because I don't think you know what your doing.....i'm asking because I want to understand it and learn. my engineering mind wants to know why i'm doing what i'm doing. sorry just had too many people take my questions wrong over the years so unfortunately I have to throw out disclaimers.

    knock box was a new term to me so I looked it up....i'm assuming you don't want me to have a box to hold my espresso...which is what came up first. so we have been going off of the knock sensors in the car which were new.
    Donny O.
    99 Hugger Orange SS convertible...mostly stock
    2000 Z28...not even close to stock. LQ4/turbo

  9. #9
    Senior Tuner SultanHassanMasTuning's Avatar
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    Donny,

    your VE will not change it will just jump to the boost EQ multiplier once your map sensor reads above 105kpa, reason i mentioned a knock box because your knock sensor seem to be disabled
    Follow @MASTUNING visit www.mastuned.com
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  10. #10
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    Quote Originally Posted by SultanHassanMasTuning View Post
    Donny,

    your VE will not change it will just jump to the boost EQ multiplier once your map sensor reads above 105kpa, reason i mentioned a knock box because your knock sensor seem to be disabled
    so basically just a different way to do the same thing? any reason to do it one way over the other? I have looked at others tunes in the repository and seen them set up both ways.

    as for knock sensors i have seen knock retard so assumed they were working as they should. you can see some KR in this scan.
    Attached Files Attached Files
    Donny O.
    99 Hugger Orange SS convertible...mostly stock
    2000 Z28...not even close to stock. LQ4/turbo

  11. #11
    Senior Tuner kingtal0n's Avatar
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    1. You need to get Wideband data imported into the scanner so the folks here can watch the wideband feed in real-time with the scan.
    google it (youtube it) theres a bunch of videos how to do this.

    when done right it will report something like this, that you can use later to more fully tune and understand how the car is running by re-watching the playback
    wbafter-a-day-of-tuning.png


    2. If you are using 93 octane it is extremely temperature sensitive. The IAT location and sensitivity is very important. Make sure the IAT sensor is working and accurate and positioned near the intake manifold (within a couple feet, after the intercooler)

    3. Since 93 (gasoline) is so temp sensitive make sure it stays cool, use an intercooler and keep it 90-105*F for safety.
    Use the IAT vs Spark tables to pull some timing when the IAT goes over say 105*F start pulling timing


    4. Pump fuel is not forgiving and neither is a cast aluminum piston. I recommend you start lower with timing and 'sneak up' on the right number by using one of many techniques. 15* for 10psi sounds like it would be okay. I run 15-16* for 7psi and gradually slope down to about 9* of timing near 14-15psi (93 only) to give you an idea.
    Maybe consider installing a water injection system (use 50/50 meth/water at first) to gain missing headroom for errors while you tune the engine and learn.
    In other words, if you have a couple extra degrees of timing by accident, or too lean of an a/f ratio, the engine will usually be damaged in one hit if using straight gasoline.
    On the other hand, if you are using a methanol spray control qty, the engine will likely survive long enough for you to eventually realize the mistake. Just don't run out of methanol.


    5. The oil dilution effect sounds like poor cruise/idle tuning.
    Notice in my picture the a/f is always around 14.5 to 15.2 in the cruise/light load regions.
    This helps keep the oil clean and the plugs clean.
    Next, make sure the engine has a full complement of PCV action during WOT.
    Here is a write up how that works
    https://www.corvetteforum.com/forums...post1600218648

    The active PCV suction at WOT when implemented properly will keep crankcase(blow by) vapors out of the engine oil so you can drive the car many miles without having to worry about the oil quality as rapidly degrading.

    6. Read up on the sloppy mechanics wiki to make sure all of your parts and information are up to snuff.
    https://sites.google.com/site/sloppywiki/

    For example
    -make sure you have TR-6 for testing and use TR-7's (Iridium IMO) for full boost (12-15psi 93 octane) gapped right (.028 to .032" but sometimes .025")
    -learn how to read plugs "timing strap" for dialing in the timing and how to tell colorization of plugs over time
    etc

    7. general advice
    -make sure your hptuner tables are smooth, use the graph visualize function to tell if there are any sharp peaks or valleys
    ex.VE table needs to look nice and smooth:
    latestve.png
    -do a search here for tuning help in the gen3 section to pick up 10+ years of advice also

  12. #12
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    Quote Originally Posted by kingtal0n View Post
    1. You need to get Wideband data imported into the scanner so the folks here can watch the wideband feed in real-time with the scan.
    google it (youtube it) theres a bunch of videos how to do this.

    when done right it will report something like this, that you can use later to more fully tune and understand how the car is running by re-watching the playback
    wbafter-a-day-of-tuning.png

    it is in there just we have our scanners set different so you cant see mine. here is the afr and afr error. now I realize its not pretty and most of the red can be explained by either being on the 2 step(he for some reason decided to use it this run even though had no traction on the brake), or being on the revlimiter. also it is set to 1 cell hit so many will disappear by upping the cell hit count.


    2. If you are using 93 octane it is extremely temperature sensitive. The IAT location and sensitivity is very important. Make sure the IAT sensor is working and accurate and positioned near the intake manifold (within a couple feet, after the intercooler)

    actually the best we have is 91 octane here in southern wisconsin. IAT was about 3 inches before the throttle body and was getting heat soaked sitting in the engine bay..so we did relocate it to just after the intercooler. there is 2-3' of pipe til the throttle body.

    3. Since 93 (gasoline) is so temp sensitive make sure it stays cool, use an intercooler and keep it 90-105*F for safety.
    Use the IAT vs Spark tables to pull some timing when the IAT goes over say 105*F start pulling timing

    i'm assuming you mean intercooler for the air not cooling the fuel. car does have an intercooler...just added a bigger one actually. I think it is 31x11x4 if memory serves me....but im getting old(47 tomorrow). I see in our tune it starts pulling timing about 131 degrees. I can change that.

    4. Pump fuel is not forgiving and neither is a cast aluminum piston. I recommend you start lower with timing and 'sneak up' on the right number by using one of many techniques. 15* for 10psi sounds like it would be okay. I run 15-16* for 7psi and gradually slope down to about 9* of timing near 14-15psi (93 only) to give you an idea.
    Maybe consider installing a water injection system (use 50/50 meth/water at first) to gain missing headroom for errors while you tune the engine and learn.
    In other words, if you have a couple extra degrees of timing by accident, or too lean of an a/f ratio, the engine will usually be damaged in one hit if using straight gasoline.
    On the other hand, if you are using a methanol spray control qty, the engine will likely survive long enough for you to eventually realize the mistake. Just don't run out of methanol.

    I have had others say to me that 15 is low....they were running 18 degrees timing. ive also compared to many others spark table in the repository and most seem very similar to mine..

    5. The oil dilution effect sounds like poor cruise/idle tuning.
    Notice in my picture the a/f is always around 14.5 to 15.2 in the cruise/light load regions.
    This helps keep the oil clean and the plugs clean.
    Next, make sure the engine has a full complement of PCV action during WOT.
    Here is a write up how that works
    https://www.corvetteforum.com/forums...post1600218648

    The active PCV suction at WOT when implemented properly will keep crankcase(blow by) vapors out of the engine oil so you can drive the car many miles without having to worry about the oil quality as rapidly degrading.

    6. Read up on the sloppy mechanics wiki to make sure all of your parts and information are up to snuff.
    https://sites.google.com/site/sloppywiki/

    i'm assuming you mean I have the MAP characteristics and injector info correct. those have all been checked...is there something else you meant?

    For example
    -make sure you have TR-6 for testing and use TR-7's (Iridium IMO) for full boost (12-15psi 93 octane) gapped right (.028 to .032" but sometimes .025")
    -learn how to read plugs "timing strap" for dialing in the timing and how to tell colorization of plugs over time
    etc

    we are using tr7's and gaped to the recommendations given. I do know how to read the timing straps. would be a lot easier if you could pull plugs on this engine without removing the headers....its a lot of work to do it every "log session" or "run"

    7. general advice
    -make sure your hptuner tables are smooth, use the graph visualize function to tell if there are any sharp peaks or valleys
    ex.VE table needs to look nice and smooth:
    latestve.png
    -do a search here for tuning help in the gen3 section to pick up 10+ years of advice also
    the VE table was still a work in progress. adjust by percentage, smooth, adjust by percentage, smooth, rinse and repeat(which reminds me I have a dentist appointment tomorrow..LOL) I have searched here, youtube, internet in general, talked with others unfortunately not many in my area trying to do this that I know. I am in the engineering field so in general I tend to over analyze everything, reasearch, read, try to learn as much as possible. I cant even try to guess how many hours I have into this already since getting the car in january. I just cant help but think there has got to be something major that stands out that i'm just missing. engines are cheap but not that damn cheap. hope that added some useful info at least.
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    Last edited by Donny O.; 10-09-2019 at 04:08 PM.
    Donny O.
    99 Hugger Orange SS convertible...mostly stock
    2000 Z28...not even close to stock. LQ4/turbo

  13. #13
    Senior Tuner kingtal0n's Avatar
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    I never checked your logs or tune because I don't have HPtuners on this computer so I had no idea you had the wideband data imported, thats good

    I did look at the pic you posted of a/f ratio and found something suspicious

    dearwhoeveryouare.jpg

    looks like engine goes lean up top?

    Your air temp is high if it's over ambient (a joke, sort of)
    seriously though get the largest intercooler as you need to get the intake air temp down near ambient for the whole run of whatever you are doing.
    Otherwise it doesn't matter what timing you use- something will ignite one of the events (it just takes one and how many are there per second at 6800rpm? homework) and the pressure will escalate and shatter engine parts like glass. Cast aluminum is an incredible alloy for daily driving but it must be kept cool, (turbocharged engines from the factory are typically piston oil-squirter equipped when cast aluminum is used) and you can't make a single mistake because she won't forgive you.

  14. #14
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    Quote Originally Posted by kingtal0n View Post
    I never checked your logs or tune because I don't have HPtuners on this computer so I had no idea you had the wideband data imported, thats good

    I did look at the pic you posted of a/f ratio and found something suspicious

    dearwhoeveryouare.jpg

    looks like engine goes lean up top?

    Your air temp is high if it's over ambient (a joke, sort of)
    seriously though get the largest intercooler as you need to get the intake air temp down near ambient for the whole run of whatever you are doing.
    Otherwise it doesn't matter what timing you use- something will ignite one of the events (it just takes one and how many are there per second at 6800rpm? homework) and the pressure will escalate and shatter engine parts like glass. Cast aluminum is an incredible alloy for daily driving but it must be kept cool, (turbocharged engines from the factory are typically piston oil-squirter equipped when cast aluminum is used) and you can't make a single mistake because she won't forgive you.
    Awe come on now. i've been reading this forum for almost a year and every time someone post a question the first response is always "you have to post a log and tune so we can see it"....so my very first post ever I do just that.....and ya don't even look at it!! hurting my feelings over here...LOL

    the lean up top i'm guessing that was when it was on the limiter.....had the cell count at 1 for that photo and average so it shows everything. if I up the cell count that goes away. shift points were 5000(2nd), and 5500(3 and 4) so it was spinning first and shifted and blew past the shift point for 2nd before it had time to shift to 3rd....boom limiter!! just to be clear it did shift to 2nd as it was supposed to but tires were already spinning and they just spun up faster and RPM never dropped just kept going up. Traction should keep us off the limiter if that is what is causing engine failure.

    we did just put a bigger intercooler and it is as big as will fit....actually the bumper support got spaced out even for it to fit. as I said I think it is 31x11x4 from CX racing. I attached pictures...video captured pictures so not great. showing how open the front is as well.
    Attached Images Attached Images
    Donny O.
    99 Hugger Orange SS convertible...mostly stock
    2000 Z28...not even close to stock. LQ4/turbo

  15. #15
    Senior Tuner kingtal0n's Avatar
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    limited reasoning
    make sure you use a fuel-cut limiter and set it low enough to prevent engine damage during tuning. The engine should not pass say 5500rpm until you tune it properly up to that point. Once the engine and shift point tuning is well refined after many hours of tuning, you can gradually raise the shift and limiter points.

    The idea is to NEVER touch the limiter if possible after say 6,000rpm. This is why low rpm limiter-shift tuning is so important to do first. Most engines (even stock) are fine sitting on a fuel-cut limiter below 5600rpm- it is very safe if done properly and gives you experience with how the engine acts or can act (say, blow through a shift and hit the limiter etc...)
    Once you have it 'figured out' then you raise both limiter and shifts, and NEVER touch the limiter again if possible.
    -The rpm shouldn't be able to rise past the limiter and especially don't want to be on the limiter at ALL after say 6,000rpm.

    air temp and pressure test
    As to the air temp. If you have a good intercooler and seeing a temp rise with such low boost (10-15psi is 'low')
    then there is a big problem. It likely has an boost leak.
    I should have mentioned this in my first post but there are so many things i just forgot

    rule#1: Always pressure test plumbing start at the compressor inlet through to the engine manifolds using compressed air.
    https://www.youtube.com/watch?v=rYZmZqn3-x0

    Every air molecule that the compressor wheel imparts energy to that is lost to the atmosphere via a leak, causes additional exhaust gas pressure rise in the turbine in order to extract that energy in the first place.
    In other words, if you create a small leak in the plumbing, then demand the same boost pressure. Well now flow rate has to be higher because the compressor has to make up extra flow to also feed the leak, therefore compressor wheel speed now needs to be higher than it should be. Which creates additional demand on the turbine via wastegate signal, and walaa you overheat the intake air, and overheat the exhaust gas, cause high rate of thermal expansion of parts and sky rocketing EGT (you don't have an EGT gauge, do you?) and wham- busted engine even from low boost.

  16. #16
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    I will absolutely take your advice and lower the rev-limiter and shift points til we know we have traction figured out.

    do not have an EGT...we did build a tester to do a boost leak check though. that was part of fixing the past owners "cobble job". leaks everywhere even a hole in the intercooler. replaced lots of piping and fixed a leaking BOV and even had a hole in the original intercooler. we have also put a bead, ridge whatever you want to call it on the end of every hard pipe to keep the silicone hoses from blowing off. I attached a picture of our boost tester, and a picture of random un-needed wiring that was everywhere, and a coupler they had coming off the turbo when we first bought the car to show how bad they had cobbled it together. not to mention the wastegate had no fire ring, a ball valve going to a make-shift heater, wire nuts on some of the electrical, and so many more things.
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    Donny O.
    99 Hugger Orange SS convertible...mostly stock
    2000 Z28...not even close to stock. LQ4/turbo

  17. #17
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    pump or ethanol?

  18. #18
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    Quote Originally Posted by lukearmstrong1990 View Post
    pump or ethanol?
    pump.

    so update. got engine 3 in the car and fired. this is a bone stock 5.3 with 150k. swapped valve covers, intake and oil pan. fired up, did some tuning cuz obviously was gonna be way off due to no big cam in this one. drove it a little while tuning and all of a sudden no oil pressure again. oil smells like gas. so did closer inspection of the past 2 engines and both seem to have trouble with cylinder 7. looks far richer than the others. long story short and i'm sure will get comments about it anyway. did not bother going through all the testing as we were short on time so a new set of injectors were ordered AS THEY WILL BE NEEDED ANYWAY FOR ANOTHER BUILD. put them in the next day and even though they were supposed to be the same deka 80's that were in there the car ran like total crap. huge idle surge. so we didn't make it to the track they day we were working towards. I eventually found the injector data for them and it was different than what was in my tune so I changed all of those settings....then had to adjust fuel a little but then fired and runs. also changed oil and have pressure again. few more drives and logs and adjustments it seems to be running ok. havent' put enough driving to have the fuel in oil problem yet so not sure if that solved it.

    not sure if it is the exact reason but the other problem I have now is the throttle body has already been drilled and with stock cam I think its too much air so does not want to idle below like 950. iac at 0, so I have some work to do there as well, but in the limited time I have had it was not my main concern.
    Donny O.
    99 Hugger Orange SS convertible...mostly stock
    2000 Z28...not even close to stock. LQ4/turbo

  19. #19
    Senior Tuner kingtal0n's Avatar
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    don't know if i mentioned or not but
    1. keep the a/f 14.6-15.2 when cruising/idle to keep from fouling plugs, wasting fuel, and contaminating the oil
    'power' transition to richer air fuel ratios can begin near 70-80KPA

    2. perform injector continuity test is essential element.
    Remove ECU plug and put one end of multi meter in the injector wire at the ECU
    Put the other end of multi meter into the power source for injector, as far from injector as possible (I found injector fuse and test from there)

    Then look for correct resistance on multi meter. Mine shows 14.6Ohms. Now wiggle the injector clip and tug the injector wires. Try to make the Ohms reading waver or change by moving the connector. I had two bad injector connector clips on my car, for example. The ohms would change when I pulled on the clips. NOT GOOD. This will create lean cylinders and misfires and mis-tuning since the wideband takes an average read.