I AM STILL TRYING TO FIGURE OUT WHAT IS GOING ON WITH THE LATEST MODS I HAVE MADE ie..POWERLOGGER, ALKY SYSTEM, AND TT ALKY CHIP. ON THIS LOG I MADE TWO WOT TESTS. THE FIRST FROM AROUND 40MPH UP TO 90. THE SECOND FROM 0-65MPH. THE ONLY THING THAT JUMPS OUT AT ME IS THE O2'S DROP TO ALMOST NOTHING AS SOON AS THE BOOST COMES UP. i HAVE NOT TOUCHED THE PAC SINCE INSTALLING YOUR KIT.THE GAIN CONTROL IS BETWEEN 1-2. AND I HAVE THE BOOST SET AT 25PSI WITH NO KNOCK AT ALL. I HAVE NO IDEA WHY THE O2'S WOULD JUST DROP OUT. THE O2 SENSOR IS A BRAND NEW AC DELCO WITH THE PURPLE WIRE AS YOU RECCOMENDED. MY GUT FEELING IS THAT I'M SPRAYING WAY TOO MUCH METH. THE BLM AND INT ARE PERFECT AT 128. ALSO @WOT THE CAR FEELS FLAT. IT PULLS STRONG AS THE BOOST IS COMING ON BUT FLATTENS OUT RIGHT AWAY BUT IS STILL SMOOTH.
calling julio/alky experts pls review my pl log
- Thread starter wb's87
- Start date
No, if you had way too much meth it would read in the high 800's for O2's.
I hate to say it, I would put in your old O2 sensor see if there is a change. Another thing it could be is a loose O2 sensor, bad engine ground, wiring harness issue, ecm issue, etc.
O2's should not drop to zero like that. Period. Alcohol wont cause that.
Understand the O2 sensor is a simple 2 wire device. One wire is its bodya nd it gets ground from the header. The other wire(purple) is the signal to the ecm. If you floor it and there is a breach on the ground or purple wire.. it will drop to zero.
I cant think of anything else to cause this.
I hate to say it, I would put in your old O2 sensor see if there is a change. Another thing it could be is a loose O2 sensor, bad engine ground, wiring harness issue, ecm issue, etc.
O2's should not drop to zero like that. Period. Alcohol wont cause that.
Understand the O2 sensor is a simple 2 wire device. One wire is its bodya nd it gets ground from the header. The other wire(purple) is the signal to the ecm. If you floor it and there is a breach on the ground or purple wire.. it will drop to zero.
I cant think of anything else to cause this.
berserker6
Assistant to the regional manager
- Joined
- Oct 1, 2009
i would really like to be able to read these zip files when i come across them. could someone tell me what program they use to open them?
Julio do you see anything else in the PL log that would cause the car to be flat under WOT? I have been trying hard to get this car tuned but seem to be treading water with it.
russgoodman
Member
- Joined
- Jul 15, 2006
You can download the PLC software on full throttle's forum, Full Throttle Speed Tech Support - Powered by vBulletin
As for the topic, Ive seen several threads pop up lately describing the exact thing with the o2s. It acts fine at idle but drops out when in boost. The common denominator is.......the new delco O2 sensor. Glad you got it figured out.
New springs would be the first thing I would do. Several vendors that help sponsor this board can help you; I think Mike Licht and Jack Cotton carry springs, and the GSCA has them for sale. I have K-Motion springs I bought after talking to Tom at Champion and I'm happy with them.
Have you done spring cleaning items; particularly, installing a new fuel filter and cleaning/changing the air filter? I wouldn't be asking you this question if I didn't have first hand experience with that situation.
After that, I'd find Julio's step by step guide to tuning with alky; it's a sticky on this category. First thing is to be sure your car is running well without alky before you start using the alky.
With a cold air kit and the FMIC you have, IAT should be at or near air temperature. IAT is a component of fueling so it needs to be reasonably correct.
So as not to give the wrong impression. My car is a show car. I take it to the drags about 5-10 times a year, and drive it 2-3 times a week and it has only seen rain about three times in it's lifetime. that being said the car actually ran great before i put the tt 5.6 alky chip and alky system on it. it ran consistant mid 11's. now my best run has been a 12.17 @ only 103 mph. i am meticulous as far as the spring cleaning things. the car had new plugs gapped @.032, new fuel filter, new k&n 9" filter, oil change, all since May. I was following the step-by-step guide and my BLM were high due to an old vacuum line. I changed out all old vac lines and BLM is now 128. That was where I left off. I am definately missing something though. with the alky gain set at 1-2 i do not get any knock retard. if I turn it off completely the first green light on my knock gauge will come on sometimes at WOT but not always. What can I do to get the IAT down?
My point was that we sometimes look for gremlins when it something basic that we just overlooked.
I believe the valve springs will make a huge difference in your car. The drop in your back half gain in speed in probably pretty big but new springs should cure that.
You either have a bad sensor or one that is getting hot air due to its location on or near a heat source which could be the upper radiator hose. I'd track that down and if that's not the problem, I'd replace the part if I couldn't borrow one from a friend to try. IAT is big factor in fueling so that number needs to be reasonably accurate.
As a reminder, you need to run higher boost level when running alky or you can get knock from being too rich.
Hope you get this fixed soon.
I believe the valve springs will make a huge difference in your car. The drop in your back half gain in speed in probably pretty big but new springs should cure that.
You either have a bad sensor or one that is getting hot air due to its location on or near a heat source which could be the upper radiator hose. I'd track that down and if that's not the problem, I'd replace the part if I couldn't borrow one from a friend to try. IAT is big factor in fueling so that number needs to be reasonably accurate.
As a reminder, you need to run higher boost level when running alky or you can get knock from being too rich.
Hope you get this fixed soon.
I just took a little ride and the car seemed to perform a lot better. prior to going i adjusted the boost down as low as i could make it. i removed the rod end and then screwed it on three turns. i didn't feel comfortable with any less. i also turned the fuel pressure down 1-1/2 lbs to 41 1/2. and alky gain up to 3. boost is now at 22lbs. these adjustments made a big difference. the car pulled hard and smooth all through 1st gear and mostly through 2nd. it did nose over at the high end of 2nd though. i really think my major problem is fueling and alky adjustments. i will address that IAT first thing before anything else though. i'm sure if i can get this down close to ambient that it will make a great difference in performance.
Well a couple things. Understand first is get all the sensors reading properly. Then work on tuning.
If the car runs mid 11's then put the car the way it runs mid 11's and confirm it runs mid 11's. Once that is setup.. then move forward. 103 MPH the car is nose diving hard.
The volt booster will not effect ET. Take that off. It will make the alky kit really aggressive. So put alky knob on 6 and leave it alone. Put chip in and let it learn. Once these two have been met.. start cranking boost into it. Typically most alky chips will level off fuel wise at 24-26 PSI. Anything less they will be rich.
not to discount a bad fuel pump, weak valve springs, etc.. but these items are off the list once the car runs the mid 11's like you say it does.
Thanks for showing interest. It seems to me that i may still have a vacuum leak somewhere. I spent most of the weekend under the hood. I bought and installed a new intake air temp sensor. Just to make sure the IAT is the sensor prior to the Maf correct? (Advanced auto calls it a charge air temp sensor) This is the one I replaced. I cleaned the MAF and sensor and screens. The Iat is still pretty high. I took a ride at 5am this morning and the IAT was about 115 degrees, actual temp was about 65. Its weird because the air filter, MAF and Maf pipe are cool to the touch. However the Maf pipe was pretty hot at the point it intersects with the up pipe. I also replaced the vac lines going to the fuel evap canister, the ball thing behind the ds front tire(I dont know what it's called) and cruise control. I found that the o-ring on the tube going into the fuel canister was off of the tube and just sitting in the hole. I ordered a new filter for the evap canister. If you have any suggestions I would appreciate them. Thanks Bill
It should be between the air filter and the MAF and look like this.
//http://www.gbodyparts.com/popup_image.php?pID=949&image=0&osCsid=d81fc69b6512d7526a791249589113ef
I use a tester to find air leaks. I bought one from Mark Huffman but I didn't see them on his website. Google "boost leak detector" and you'll find out more than you probably want to know.
Have found leaks in places I never thought about such as the throttle shaft seals in the throttle body.
Julio is right. Put your car back where it was and see if it still runs good. If so, think that if your computer starts acting up unexpectedly, the first suspect should be the last thing you put on. Same for your car. I'm not sure what would be best order to turn back on your additions. PL is probably a safe bet for #1 but after that, I'd probably pose that question to Eric Marshall/Steve Wood on the TT forum.
Keep us informed.
//http://www.gbodyparts.com/popup_image.php?pID=949&image=0&osCsid=d81fc69b6512d7526a791249589113ef
I use a tester to find air leaks. I bought one from Mark Huffman but I didn't see them on his website. Google "boost leak detector" and you'll find out more than you probably want to know.
Have found leaks in places I never thought about such as the throttle shaft seals in the throttle body.
Julio is right. Put your car back where it was and see if it still runs good. If so, think that if your computer starts acting up unexpectedly, the first suspect should be the last thing you put on. Same for your car. I'm not sure what would be best order to turn back on your additions. PL is probably a safe bet for #1 but after that, I'd probably pose that question to Eric Marshall/Steve Wood on the TT forum.
Keep us informed.
