I just want to expand on my thoughts a little more. I think the spacer or tube that causes the iac air to dump into iac passage of intake is worth doing and wont hurt anything given its done safely. I do not think that will solve your idle issue as it is more geared to solving split blm so it could improve a rough idle. The through hole is pretty much done so the throttle blades can be fully closed and the iac passage gets the proper amount of air. Again its more of a fine tuning and again is to help the split blm and it will affect the iac count. The reason the mods help is because air dumped in the plenum gets distributed poorly between cyllinders. The iac passages distributes the air the best. .......... Now onto my concern. It doesnt really sound like this will solve your problem. My opinion is these mods are more for a car that idles(dont get me wrong I do believe running idle air in iac passages is better than dumped into plenum)but its a rough idle and split blm. I agree with Fred that getting your o2 working is important and I also would see about opening the blades via the screw as well. Pretty much I would examine and share your idle a bit better. Can you get it to keep rpm by holding blades open(using the screw or steady pressure?) or does it require feathering ? Did you check the resistance of the iac valve coils? Because you speak of how hard you are working at keeping it at idle speaks of other problems. The o2 effects fueling so thats important to solve that.. The iac valve could have been damaged as well (thats what happened to mine alot of people change theirs and it doesnt help but as bad as it sounds you are fighting to keep at idle reminds me more of my issue except mine would sometimes stick at a high idle but when it wanted to stick on a low idle I had to be all over the throttle to keep it running. Does your car run good other than just not wanting to idle?........ For file sharing I could not figure out a regular site so I was advised google doc- google drive and I figured out that site.


Posted from Camaroz28.com App for Android

 

Injuneer- I am sorry if I sounded annoyed. I do appreciate your help and as you and slick1hunting mentioned I think it is worth looking into the O2 problem.

The car will remain at a steady idle. I can hold it as low as 600 and it'll set there and lope, its just that as soon as you release your foot it dies. It did surge on me only once though. I will mess with the idle screw tonight as well.

I also agree that I don't believe opening my IAC passage will cure this problem because from what I've read goes right along with slick1 saying it is more of a fix for fine tuning a rough idle. Nevertheless I think it won't hurt to do.

This brings up another concern though, I am planning on running a nitrous outlet plate system. Being that this mounts between the TB and Intake, will it too need drilled? Does it already have holes for IAC passage? Does anyone have experience with this?

My main concern now is getting the car to idle, so the nitrous can wait. I'll get a .csv file up whenever I get home from work tonight so hopefully you guys can help me out some more.

Thanks for the replies and patience. I work about 50 hrs/wk and go to college in the evenings so it's hard to get time to work on it, hints why I had to take a weeks worth of vacation just to get the motor in the car lol

 

I run the nitrous outlet plate. It does have a hole or provision to let air into the iac passages of the manifold. It is about a 3/8" hole. I drilled mine to 1/2" but that is only because I used a tube rather than a cut spacer to direct the air and needed the extra room. The plate may have a tendancy to throw the idle blms off too as I have read of problems dissapearing with removal of plate. I may not be any help with the datalog because I am learning myself and am getting pretty familiar with my software and some things to watch but if it isnt something ive experienced or doesnt show up in a similar format I may be of no help and even worse lol. Fred is the man, very knoweldgeable. I still have my eye on a problem with your iac valve but thats mostly because I assume you have some of the problems I had. If it does come to it and you need to replace I found mine on amazon for a good price for genuine ac delco(dont get cheapo knockoff brand) Posted from Camaroz28.com App for Android

 

Alright guys I got the car to idle on its own. I adjust the screw pretty far out, but it is idling.

I have .csv files but I am not sure how to upload them????

I have server filezilla, but I can't figure it out

 

Ok I gave up on trying to figure out filezilla. I used uploading.com there are two different .csv files. Neither file is when I am driving because my car is not driveable at the moment.

http://uploading.com/dce7m6f7/DLOG-2013Aug13-203238-csv

http://uploading.com/379fdc5d/DLOG-2013Aug13-201939-csv

 

You need to find another FTP site. That one is set up to fool people into clicking the wrong "download" button, and loading unwanted software on your PC. My virus system prevented me from opening the file.

 

https://kgerdon.opendrive.com/files?...Mzc4NF8wV0NBYQ

https://kgerdon.opendrive.com/files?...Mzc3OV9RUmFFUQ


Try these. They are through a top rated FTP site, should be secure.

 

https://kgerdon.opendrive.com/files?...Mzc4NF8wV0NBYQ

Here's another that is much longer than those two.

I'm new to reading these, so correct me if I am wrong. This is what I'm interpreting and the solution. Again, please tell me if I am missing anything or am wrong about something.

BLM seems good. It only strays from 128-128 one time

IAC is high. Want around 35-40. Drill Mod will help.

TPS voltage is high. Want around .67. Slot TPS.

 

Your TPS voltage should be closer to .5v than .7.

The IAC counts are high but not maxed out. 35-40 might work on a stock car but with bigger heads and cam the motor will naturally want more air. I wouldn't drill anything yet. In fact, I'd be willing to bet your Chinese throttle body is playing a big part in why the car won't idle.

You're also showing low map readings as well as a code for low vacuum. Which LE cam are you running? Specs would be handy.

Your BLMs appear to be locked but hard to tell without seeing the tune. Your O2 sensors are either shot or the car is ridiculously rich. DTC 63 means the right sensor isn't working at all.

You're also getting several degrees of knock retard which usually means the rockers are being noisy and should be adjusted or your pushrod length is wrong. This could also affect the MAP readings.

I'd start by checking the pushrod length on the motor to make sure you have the correct length. Decking the block, surfacing the heads and different gasket thicknesses will all play havoc with pushrod length. Next follow the instructions on Shoebox's site for properly adjusting the valves if you're not familiar with the process. Check the intake for vacuum leaks and stick the stock throttle body back on the car for the time being. And, of course, fix your O2 sensors.

 

Thanks for the reply 97ws6. When I put the engine together I used ls7 lifters. Then measured what pushrod length I needed once my rockers came in. They are:

Trickflow Chromoly Pushrods 7.2" Part# TFS-21407200
Trickflow 1.6 NSA RR's Part# TFS-31400521

My cam spec is 232/240 .579/.576 lsa 110.


I am not hearing any noise from the rockers and I am pretty confident I have the correct length and have adjusted the valves correctly.

I do hear a pretty loud whoooshing sound almost like a procharger sounds. So that could be a vaccum leak. I'll check that tonight after work.

I've also ordered two new o2's that I'm picking up after work. And I'll find my stock TB.

What do you mean by BLM's being locked up? I thought it seemed odd they stayed so perfectly matched.

Thanks again.

 

What you call a "longer" file is not very long. It ran for 152 seconds, and then appears you restarted it. You are also only recording a frame of data every 6 seconds - way too long an interval. You need to get it closer to 5 frames or more per second to get meaningful data. I've received files with over 10,000 lines of data.

It's still in open loop, because it typically take 205 seconds to enter closed loop, assuming your coolant is warming up (yours got warm enough) and the O2 sensors are hot enough to start working. [b]Because it's still in open loop, your LTFT's (BLM's) and STFT's (INT's) are all 128[b]. They are not locked. That's what they show in open loop, cold, and O2's are not working. They mean nothing until it enters closed loop.

Your right O2 appears to be disconnected or burned out. The volts stay around 0.45V, which is what the PCM supplies. The sensor is not generating any voltage of its own.

I would disagree that you need any specific TPS closed throttle voltage. The PCM will accept anything between 0.25 - 0.90V and baseline that as 0% open. Your 0.71V is fine. Most unmolested stockers will read 0.65-0.67V. 0.50V is a holdover from the 3rd Gens, which had an adjustable TPS sensor, and a PCM that would not auto-baseline.

You basically have no significant intake manifold vacuum (partly because you are holding the throttle open). You have knock retard all the time. I am wondering if you have the timing set installed correctly.

 

https://kgerdon.opendrive.com/files?...Mzc4NF8wV0NBYQ

That's a link to my file from tonight. This data log shows my new o2's installed. I kept the aftermarket throttle body on. I let the engine run longer about a half hour. It died on me once I think. It also kept surging up to 3-4 grand. Generally if a gave it a little tap on the throttle it would come back down. From idle, it seems to hesitate when I punch the throttle quickly and hesitate to come back down promptly to idle.

I too am beginning to think my timing might be off just by the sound of the engine. I do know Brian at PCMforLess said he was going to retard some of the timing at higher rpm's for the nitrous. Other than that I am not sure of what else was done to the tune other than me giving him my list of mods.


Just for reference here are some if they will help you guys read the data correctly:

Stock crank
Block was squared, decked, honed, and bored .30
Pistons sealed power pistons hypercrappy (they were new and I got them free so hey)
Heads had minor port job with valves/spring upgrade.
ls7 lifters
7.2" trickflow chromoly pushrods
1.6 NSA trickflow RR's, trickflow guideplates
Stock intake
32# injectors
52mm Professional Products TB
Cloyes double roller timing chain.
LE Cam 232/240 .579/.576 lsa 110
Meizerrie HD water pump
Pacesetter Mid tubes
NGK iridium plugs
Summit plug wires
AC Delco new opti
ARP bolts/studs everywhere

I think that's pretty much it. Is there a way I can determine for sure if it is out of time?

Also, Injuneer I cannot find an option to increase my scan interval on the Scan9495 software. I hope this file is long enough to be useful for you all.

Thanks everyone.

 

Could I be getting false knock readings? With the car running sort of rough causing vibration, would it cause my knock sensor to false read? It is a new sensor I just bought, I suppose I could have over tightened it. I think 14ft lbs is the spec.

Also, I forgot to mention towards the end of the data log I did drive the car down the driveway and back. I can't take it down the road yet without tags, plus hood, bumper, lights are off so I can paint it.

On the plus side, I think my new o2's are working.

I've built other engines before, but this was my first lt1. To my understanding you can't really mess up installing the timing set. I mean line up the marks tdc and opti only goes on one way. Is this wrong?

Sorry for all the questions, I am trying to gain a better understanding of these data readings. I'm used to old school 302's and 350's, so it's new to me.

 

This log is with the TB hole drilled. 5/32" same size my stock had. I also found where a vaccum leak was occuring and fixed that. And I changed plugs and oil/filter. It idles great now, but is still popping. Number 8 spark plug was clean too, while all the others were blackened. 8 is getting fire, I checked that. I've made some progress, can anyone read this log and help me figure out the popping and why one bank BLM is lower than the other???

https://kgerdon.opendrive.com/files?...NTA2Ml95ZHJ1eQ

 

Bump. I was really hoping to get her running good before the ltx shootout.

I've made some more adjustments to the car and it seems to be running better now. Although at idle my exhaust is clanging and casuing a false knock retard. I'm going to fix that this weekend. I have another data log if anyone at all is willing to look it over and help me out.

Thanks