I have odd problem. My GN has a Red Armstong 93 chip, XP pump and adjustable regulator. With only 25psi at idle with the vacuum line off. I get O2 readings from .85 to .91. When I had it at the recommended 45psi at idle, I had readings of .95 to .99. I'm also get 2 to 8 degrees of knock retard. My boost is set at 17lbs. That acts a little odd also. It climbs to 19lbs drops back to 14lbs then climbs back to 17lbs and stays threre. This testing was done only in third gear since it was on the street with street tires. Any ideas would be greatly appreciated.
Ken Williams
87GN
I forgot to mention in my first posting, that I have blue top injectors and the chip is supposed to be for blue tops. The chip has 667 and R93 written on it.
Ken
I would first start by trying a different fuel pressure gauge to make sure the numbers you see are right. Just to be sure.
Does the pressure change at idle when you put the hose back on? Need to make sure the regulator is working correctly.
What are you using as a scan tool?
Depending on your setup, your boost fluctuation may be due to a need to port the wastegate hole in the turbine housing. When these cars start flowing more air, this hole can be restrictive and cause boost spikes and such.
Thanks Scott. I'm going to have the press gauge checked at work. The reg. pressure does go up when you unhook the vacuum line. I'm using a OTC4000E scaner that I bought from thr club a couple of years ago. I have a home built cold air package with a 9 inch K&N. The air flow numbers run about 180 to 200. I talked with a guy today and he said that the O2 sensor could also be bad. I have a ported exh. elbow and ATR 2.5 down pipe. Sounds like its time to put them on. They might help my boost problems.
Ken
When you say that your air flow numbers are running "180-200", do you mean those are your MAF readings? If so, then I am suspicious of your MAF. With your set-up, you should be coming close to the 255 limit of your MAF at 17psi boost. 180 sounds pretty low to me.
Is this what you meant by 180-200?
Mike
The OTC monitor gives both MAF and ARFLO numbers. They usually run the same but I didn't check when I was testing. I do know that when I added the cold air package the numbers went down to close to what they are now. I question this and list members said that was normal.
Wide open throttle and max boost should generate MAF numbers of 255 (or very close to it, but that's another matter). I'm in agreement with Mike that you may have a bad MAF or perhaps a leaking or damaged MAF hose. Don't think the downpipe will cure the problem.
I don't recall the OTC displaying ARFLO for these cars. Just the MAF number. Are you viewing/recording this data in 'Road' (#9) mode or ALDL (#8) mode? You should be using Road mode, which might take a little 'trick' to set up. Do you know how to set it?
CHECK YOUR HOME MADE AIR SYSTEM. A FRIEND OF MINE
MADE ONE AND HIS CAR WAS RUNNING BAD. GO BACK TO YOUR OLD SYSTEM AND SEE IF YOUR # COME BACK UP TO AROUND 235-255
Well guys, I called John today at Red's and it turns out the guy I bought my chip from sold me one for stock injectors not blue tops. John is very good to deal with and very knowledgable. As soon as I read him the numbers on my chip he told me my problem. I mentioned to him about my low flow numbers and he said get the right chip first. So I'm going to get the correct chip and start tuning again. Thanks for all the help so far. I'll let you know how things turn out.
Ken
87GN
Given that the 'blue top' injectors flow about 20% more than the stockers, that would sure explain the odd fueling. Sounds like you're on the right track.