928S4 Cutout problem
03-02-2010, 01:25 AM
#16
Nordschleife Master
If the CPS (crank sensor) has a dot on the end of it, replace it iirc they are around $54 from ROG100 here on the list.
You say you replaced the FP and brain relay. Which brain? There are two brains, and 2 relays.
EZK and LH. Both should be exchanged.
I would confirm about the shorted injector harness, and I would also recommend if you havent got a rebuilt LH for your car to do that.
Roger in Texas, or Louis Ott in OR.
You say you replaced the FP and brain relay. Which brain? There are two brains, and 2 relays.
EZK and LH. Both should be exchanged.
I would confirm about the shorted injector harness, and I would also recommend if you havent got a rebuilt LH for your car to do that.
Roger in Texas, or Louis Ott in OR.
03-05-2010, 12:45 PM
#17
Both brains have the new relays as well as FP. I agree, if that sensor looks compromised I should get a new one.
But are you suggesting I get a new LH as well?
I will check the injector harness as well, and relook at everything. The fluctuating idle may be a new clue, this problem could be just about anything.
But are you suggesting I get a new LH as well?
I will check the injector harness as well, and relook at everything. The fluctuating idle may be a new clue, this problem could be just about anything.
03-05-2010, 01:24 PM
#19
Shameful Thread Killer
Rennlist Member
Rennlist Member
Anyway, took it out for a drive, and while it didn't do the cutout trick( of course this was intermittent anyway), it did do something else: Get on the throttle (4k rpm) then lift foot off accel and push in clutch. Car RPMS drop to ALMOST zero (no stall) then hunt back to 5-600 rpms.
Did this a few times, then it just started working better. Same test, dropped to 800 rpm rock solid idle. Then a few times later, once when I wasn't on the throttle, dropped to zero then it stalled. Started right up again.
I'll check the Hall on the pass side today too. Still weird.
Did this a few times, then it just started working better. Same test, dropped to 800 rpm rock solid idle. Then a few times later, once when I wasn't on the throttle, dropped to zero then it stalled. Started right up again.
I'll check the Hall on the pass side today too. Still weird.
03-05-2010, 04:56 PM
#20
Addict
Rennlist Member
Rennlist Member
What does the brains trust think of this speculative theory ?
Intermittent short to ground in the wiring to pin2 (idle) of the TPS switch. or in the TPS switch itself.
This would tell the LH that the throttle was closed and fuel accordingly ignoring the MAF signals, causing the revs to drop to idle speed.
Intermittent short to ground in the wiring to pin2 (idle) of the TPS switch. or in the TPS switch itself.
This would tell the LH that the throttle was closed and fuel accordingly ignoring the MAF signals, causing the revs to drop to idle speed.
