Hi all,
I'm a newbie to the world of GN's and EFI tuning but not to the world of fast Buicks. I recently traded my '69 Skylark 455 for an '87 GN. (unfortunately the 455 was faster than my GN now but I'm hoping to change all that!)
With the great help of Jay (who I met on this site), I have found that I'm having MAF sensor issues (among other things) since even under WOT, full boost, and building RPM, the MAF readings, according to my DirectScan runs, is dropping out and then building again, and generally quite erratic.
I have cleaned my filter, checked the intake path and everything seems ok.
Any insights from anyone would be greatly appreciated. Also, if you are so inclinded, I would greatly appreciated it if someone could review my DS files and provide comments (we can take that discussion off line).
Thanks a bunch.
Scope
scope169@yahoo.com
We will need a little more info on your setup. Or is it totally stock? I will be happy to look at the ds files. Email them to me at sully@carolina.rr.com
To make things easier, I posted his DS runs on my website..
http://www.wideopenwest.com/~morpheus99/DS/
Also - besides that wacky MAF and inj. PW, check out his RPM ramps..valvesprings?
I looked at the runs. You hmust either have a bad MAF or some really wicked airleak after the MAF. Take a look at the pipe that goes from the maf to the turbo for large tears or holes.
looking at test3 at 37 MPH YOu have been at WOT for long time and MAF is only 171 which is causing your injectors to only run at 66%. Problem is you are getting a lot more air than 171 cause your o2 are down to 92. You data indicates that the car is maxing out the maf only it doesn't know it and is fueling for 171 g/s.
This means the turbo is drawing air in that the MAF isn't reading or the MAF is just plain bad. Is it an aftermarket MAF or stocker?
The MAF sensor is stock, and I've checked the hose from sensor to turbo. No problems there.
If it is a bad MAF sensor what are my options? Is there anyone in Toronto area who has an extra or would be willing to swap just to run some tests? I don't want to spend $300 on MAF and translator if I don't need to ...
Thanks.
Hi all,
I managed to borrow a good MAF this weekend and tested it with my car. It did max out at 255 and didn't dip as RPM rose, so I guess my MAF is bad.
Anyway, I have a couple of questions for the group:
1) Are there any drawbacks of going with a chip that locks out MAF at 255? If this is a viable solution, I just as well might go for it.
2) If the above point is not recommended, should I just get a rebuilt stock MAF or should I upgrade to Impala SS MAF (3") or even LT1 MAF (3.5")? I really don't want to spend the money at this time (I just got the car this year) and if solution 1) is workable, I would much prefer that.
3) Does anyone have any experience with totally open loop chips? I've heard that some guys do this and are getting decent results, i.e., setting the closed loop temp really high so the BLM's never get updated. Would going this route help my MAF situation?
Any help or advice would be much appreciated. I'm hoping to get the car in order for a local Buick day this Sat.
Thanks.