1985-1998 [Subscribe to Daily Digest] |
[Main 9000 Bulletin Board | BBFAQ |
Prev by Date | Next by Date | Post Followup ]
Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
Re: APC/BPC valve problems Posted by Ari [Email] (#2847) [Profile/Gallery] (more from Ari) on Thu, 18 Oct 2001 12:36:56 In Reply to: APC/BPC valve problems, 87 9000T, Wed, 17 Oct 2001 23:12:34 Members do not see ads below this line. - Help Keep This Site Online - Signup |
Definately go to the Townsend site mentioned by 94 Aero below. I wouldn't sweat the resistance too much, because at 3 ohms, most people don't have ohmmeters accurate enough to tell much of a difference. Basically, it should be low ohms (around 3), but not a short circuit (less than 1) or too high (over 15-20 ohms).
The Townsend document talks about when you get airflow between which ports, energized or denergized. That's what counts, period.
If you want to rule out some sort of bizarre APC solenoid heating effect, just pull the + wire out of the solenoid connector, and wire 12 volts to the solenoid all the time. You should be able to get full boost all the time, even past your 5 minute window. If you still get full boost 5 minutes later, it's not the solenoid. Be careful with this - you've just wired out all of the anti-knock safety systems. If the problem is that the engine warms up and starts knocking after 5 minutes, you'll be knocking under full boost.
I can think of a bunch of reasons to loose boost after a few minutes. The main reason to drop to base boost is knocking. The engine will knock if it runs lean. The first place I'd look is your O2 sensor. When the engine is cold, the O2 sensor isn't up to temp and isn't working, so the engine schedules fuel based on the AMM. After a few minutes, it schedules fuel based on the AMM and the O2 sensor. If the O2 sensor is bad or slow, you could be running lean after warmup, causing knock and reduction to base boost.
Under full boost you should be getting fuel enrichment. It's possible that your fuel pump, or more likely, your fuel pressure regulator isn't providing enough fuel pressure. Low pressure, low fuel deliver, and lean running.
Just some thoughts.
posted by 140.157....
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.