Messages

61

General Buick Tech / Re: I'm trying to track down a rough idle problem on my 87 GN

« on: January 13 2018, 06:56:28 AM »

Sorry on the misunderstandi ng on the "modules". When I swapped the ignition module/coilpak from my other turbo car to my GN, it is, in fact, an aftermarket module, so I guess that's why the car shuts off after unplugging the cam sensor. I'll be switching back the modules first thing todaythe other being a Delco. Also, I have one of those Casper's cam sensor caps, brand new, that I have never installed. Now may be a good time to put it on. Steve, would you do that or do you recommend loosening the cam sensor and moving it ccw?

The car does warm up properly and readings on the scanmaster are in order. It does go to closed loop normally. I'm not familiar with a light on the scanmaster indicating closed loop. Also, I'm pretty sure TPS reading sits on .042 and doesn't change unless I press on the gas, but I'll double check.

I upgraded my TT chip less than a year ago, I think it's 5.7, for more fuel and yes, the 02s are reading in the 800s on startup. I'll verify that today to be sure. I'll be looking at it in a couple hours.

It seems this problem presented itself after a cold weather snap down here in Florida. I didn't go anywhere in the GN for over a week and when I resumed driving it, that's when I noticed the erratic idle. Thanks again.

62

General Buick Tech / Re: I'm trying to track down a rough idle problem on my 87 GN

« on: January 12 2018, 08:26:25 PM »

I think they're OK. I have 50s I installed years ago, before there were 60s. As I said, it will run smooth, so if it was something like that, it wouldn't ever run smooth. This is just one of those problems that starts, out of the blue. I'm hoping it goes away the same way. 

63

General Buick Tech / Re: How To Select The Correct Turbocharger/Torque Converter?

« on: January 12 2018, 08:22:53 PM »

For how junk my car is, this 6262 and PTC 3k l/u combination is mind blowing. I wasn't expecting this turbo to spool as fast as it does on my stock engine...

Tell me about it. I installed a 6262 a few months ago after running a 44 for(ever) more than 10 years, maybe much longer. I was very impressed with the power increase, to say the least. I also purchased a 9.5 lock-up converter from Ron Husek to replace my D-5, but I still haven't installed it. To my surprise, the D-5 works fine with the 62. My only complaint is with myself. I thought I could still run 25 pounds of boost. 

64

General Buick Tech / Re: I'm trying to track down a rough idle problem on my 87 GN

« on: January 12 2018, 07:38:48 PM »

John, are you running factory ignition modules, or, are they aftermarket.  My cars run perfectly on factory modules when unplugged.  Of course, I get the check engine light.

I never tried unplugging an aftermarket module.

Just for the heck of it, you might try loosening the cam sensor and rotate it about 1/8" CCW and see if that makes a difference.  While you are at it, Check how much vertical play you have in the cam sensor cap.

Is the car warming up properly after start up as per the scantool and do you have any data logs taken during the warm up to show us?

Hello!  Yes, the TPS is an AC, or that's what it says, and the cam sensor is not aftermarket as far as I know. But as I said, it stalls after unplugging the cam sensor. Does that mean anything? And when unplugging the TPS, there is absolutely no idle variation.

I thought maybe I might be too close to a position with the cam sensor that might cause my idle problem, but I didn't get that far -- to loosen it and move it a little, so I will do that tomorrow.

Car is performing fine after warmup, though I've been staying out of WOT for fear of back fires. Of course I have a scanmaster but nothing more sophisticated.  Thanks!

65

General Buick Tech / I'm trying to track down a rough idle problem on my 87 GN

« on: January 12 2018, 06:47:31 PM »

Hello all. I'm having an idle problem. On startup, it may idle smoothly for a couple minutes and then the idle rises and falls, and gets somewhat jerky and then may smooth out. Once into normal driving, all seems well. I have swapped out (I have another turbo car) the ign. mod./coilpak, the maf, ECM, changed chips so far. I've unplugged the O2 sensor. None of this had any positive effect.

I finally got some improvement by changing the TPS. It idled smoothly for longer periods although with some, but less than before, occasional idle fluctuating. If I unplug the TPS it idles perfect. Is this typical? Though it does seem overall better with a different TPS installed, I still think it's not the basic problem.

I unplugged the cam sensor. After doing so, about 30 seconds later the car stalled out. I tried again, and it stalled out quicker. I was under the impression it would just continue to run. What might that indicate if unplugging the cam sensor caused it to stall?  Thanks in advance for any and all suggestions.