what to adjust for dying after letting off throttle . cammed lq4 is300 swap

[strokedcoupe]

hello just starting tune and having few issues .. first cant figure out what to tune to get the thing to quit dying after I rev it either sitting still or coming to a stop from driving.. it has around a 580 lift cam and im starting with a tune I had done years ago at wait4me performance when I originally bought this engine for another project.
any help on other parts of tune you see would be appreciated .. I have the tuning school.com level 1 course im using to tune with but this is really only 2nd time I've used and other was a stock ride I was just playing with but I tune many other efi racing style platforms so have understanding of the basics but hp tuners has so many other maps and adjustments it will take a while to learn..

here is the logs and file im currently using sorry actually I thought I saved log it only saved histogram from ltft. so I don't have one with me right now
car info is
is300 swap
lq4
ls6 intake / truck mass air
headers
571 lift cam with trunion conversion and pac 1218 springs
1999 5.3 Silverado ecu and harness
built 4l60e with 2800 stall
4.30 gear with lsd (factory)

[mowton]

Need to post you log files as well. They end in .hpl

Thanks,

Ed M

[strokedcoupe]

Need to post you log files as well. They end in .hpl

Thanks,

Ed M

in the post I had stated that it did not save them only the histogram which I didnt realize until posting I thought I clicked save log but it was histogram that I hit instead and ill try to get that next time I get to drive it... but is that required for a point in the right direction on my next tuning session ? not trying to be smart just trying to understand if that is a requirement to answer the question correctly or did you not catch that part of post? thanks for any info

[2xLS1]

So would that be like a 3/4 racing cam? Because just saying what lift a cam has is about as useful information as just saying it is a 3/4 racing cam.

[JasonS5555]

Yeah, we really need to see a log file before we can help. There are MANY things that can cause the engine to die off throttle. Idle air, throttle follower / cracker, to list just a few. So we need to see a log.

HTH
Jason

[strokedcoupe]

So would that be like a 3/4 racing cam? Because just saying what lift a cam has is about as useful information as just saying it is a 3/4 racing cam.

571 571 lift 276/282 duration 224/228 @50 anything else dear??? so no its not 3/4 its full race cam

[strokedcoupe]

Yeah, we really need to see a log file before we can help. There are MANY things that can cause the engine to die off throttle. Idle air, throttle follower / cracker, to list just a few. So we need to see a log.

HTH
Jason

thanks im trying to get on real quick of idle and rev.. also gear selector switch is broke and thinks its in gear all the time .. have one ordered but just keep it in mind ...

[strokedcoupe]

tune and log of idle and rev/ die it does it more at the end when it warms up

[2xLS1]

571 571 lift 276/282 duration 224/228 @50 anything else dear??? so no its not 3/4 its full race cam

Your fuel trims look awesome. Keep up the good work dear?

[strokedcoupe]

Your fuel trims look awesome. Keep up the good work dear?

um I've only made one change to the map. car just started up Sunday and I've only drove it 5 miles to get gas and logged ltft histogram ,so thanks ill take that as a compliment... apparently you are the internet police of this forum.. every good forum has at least 5-10 of them.. they go around correcting grammar and making smart comments but never really answering the question. keep up the good work..

[02statesman]

Your fuel trims look awesome. Keep up the good work dear?

LOL... That's priceless

[POWERZONE]

Your VE table needs serious work.
DO NOT GO WOT! Some of your PE functions need work.(you have a 3200 rpm delay combined with 100% TPS, Not bueno for reving or WOT).
Your spark tables need work as well.
Your MAF is partially failed.
Your TPS needs to be reset or your TB position screw is off or cable is hanging, probably just needs to be reset.

I suggest you read the material in the Tunning Book fully before driving the car. Because you have major KR and lean spots. Some of it looks like pre-ignition pinging due to your fuel trims. Until you fix the VE and Spark tables, the idle and ride will be erratic.

Set a base tune that is safe, then work from there.

[strokedcoupe]

Your VE table needs serious work.
DO NOT GO WOT! Some of your PE functions need work.(you have a 3200 rpm delay combined with 100% TPS, Not bueno for reving or WOT).
Your spark tables need work as well.
Your MAF is partially failed.
Your TPS needs to be reset or your TB position screw is off or cable is hanging, probably just needs to be reset.

I suggest you read the material in the Tunning Book fully before driving the car. Because you have major KR and lean spots. Some of it looks like pre-ignition pinging due to your fuel trims. Until you fix the VE and Spark tables, the idle and ride will be erratic.

Set a base tune that is safe, then work from there.

I think the pe was disabled to 100% while I was doing the ve table scan for the first time as per the ve tuning manual.. I turned mass air fail freq back upafter my first and only ltft scan because it wont hardly idle with out.. I haven't drove since.. its a new swap and first fire up.. and the original tune is from wait4me performance when I had pcm and harness done years ago .. I havent changed much yet.. should I start back over with my stock tune. .. thanks for the help powerzone.. im just trying to get it to idle decent before it goes to paint shop Monday so they wont be cussing me trying to pull it in and out of shop... I can fix the rest afterwards..

[strokedcoupe]

ok started over with a stock tune went by the tuning school manual for 4 ve ltft and 3 maf ltft runs tonight .. it runs much better still some stumble on way home in OD but computer was dead so couldn't log that.. but could someone look at my ve maps I know I need to smooth them but after 4 ve ltft logs it still was asking for 20 in some of the areas @ 3200 and 50kps which are at 140 now.. something seems wrong with that.. car is happier revs cleaner and doesn't die after letting off but I did make few changes that the manual told me for a cammed vehicle but only baby steps on that


here is final tune tonight and last log from ve then last log from maf ltft



thanks for anyones helpful input

[POWERZONE]

ok started over with a stock tune went by the tuning school manual for 4 ve ltft and 3 maf ltft runs tonight .. it runs much better still some stumble on way home in OD but computer was dead so couldn't log that.. but could someone look at my ve maps I know I need to smooth them but after 4 ve ltft logs it still was asking for 20 in some of the areas @ 3200 and 50kps which are at 140 now.. something seems wrong with that.. car is happier revs cleaner and doesn't die after letting off but I did make few changes that the manual told me for a cammed vehicle but only baby steps on that


here is final tune tonight and last log from ve then last log from maf ltft



thanks for anyones helpful input

What injectors do you have? If stock what year and car?

This is a N/A setup or FI?

[strokedcoupe]

What injectors do you have? If stock what year and car?

This is a N/A setup or FI?

they are the stock 21.8 99 truck injectors #25320287
N/A setup

[strokedcoupe]

cylinder #8 not firing plug still looks new .. it has spark so im guessing injector bad.. may have a few bad might be why the trims are so AWESOME..