Should I Fix this B4 DSMLINK?

[talon77]

I'll try to keep this short, but here goes... My alternator went out on me recently, so I changed it with a new factory unit and new battery. Problem solved, from a voltage perspective. Voltage now reads 12.99V with car shut off and 14.0V with car running... Cool. However, after installing battery and alternator, my car wants to stall every time I slow down for a traffic light as soon as I depress the clutch pedal. For example, tachometer reads 1,000 rpm when I am slowing down as I approach traffic light. As soon as I depress the clutch pedal, the rpm wants to drop to about 300 and the engine wants to stall. (As a side note, if I give the throttle a quick "blip" by heel and toeing, I can recover from the stall and the car will run fine again until I reach the next traffic light).

I have searched the forums and it seemed that the problem could be the ISC. I performed a check and I found all measurements to be between 28 to 29 ohms. Also important to note is that when I turn the steering wheel at idle, the rpms raise momentarily as it should. I could be wrong, but I concluded that the ISC was not the problem.

Again, I could be wrong, but I do not think that the problem is the BISS screw either since the engine normally idles very nicely (around 900 rpm), except when coming to a stop. From searching the forums, it seemed that those with problems associated with BISS normally had a "hunting" idle, which I do not have.

I haven't performed a boost leak test recently, but I am not sure if a boost leak would cause this stalling problem.

Long and short of it is that I was going to buy myself DSMLINK this Xmas, but should I proceed to buy and install DSMLINK before fixing this problem? If you guys have any input regarding how to fix the stalling issue or whether/not to go with DSMLINK yet, I'd appreciate it much! BTW this forum rocks! Sorry for the long post guys...


P.S.: My car is currently untuned, I drive it very easily (off boost most of the time). I am waiting for the DSMLINK install before I install my AFPR, Supra fuel pump, 650 injectors, and 2G MAS...

 

[Talesin]

I was having the reverse problem; when I'd be coasting down in neutral, it'd idle surge like crazy (1000-1500 every 2 seconds) and be idling at 900-1000rpm at a full stop.
Ended up being the BISS... apparently while my mechanic was rebuilding the engine, he thought the BISS was holding the TB on, and unscrewed it. Didn't put it back. Grounded the connector and set the idle, and it's been perfect ever since. Try setting the base idle first (don't forget to ground that connector!), then check your ISC. Normal idle is 750 +-50rpm.

Beyond that, the standard idle surge checklist is your friend. And yes, get the car running right before you put in DSMLink. That way, any new problems that crop up afterward can be tracked down with a known-good baseline.

 

[dalatinromeo]

I would definitly solve your problem first before purchasing DSMLink. I will fix it now, then having to spend more later because you never fixed your problem.

 

[talon77]

Talesin,

I was afraid that you guys would say that ... I'll keep working on the fix before looking into DSMLINK. For now, I'll start with setting the base idle and see if it helps I'll keep you guys posted.... can't wait to get this fixed so that I can get the link!!! If anyone had a similar problem with their dsm and is familiar with the fix, your input is appreciated

I was having the reverse problem; when I'd be coasting down in neutral, it'd idle surge like crazy (1000-1500 every 2 seconds) and be idling at 900-1000rpm at a full stop.
Ended up being the BISS... apparently while my mechanic was rebuilding the engine, he thought the BISS was holding the TB on, and unscrewed it. Didn't put it back. Grounded the connector and set the idle, and it's been perfect ever since. Try setting the base idle first (don't forget to ground that connector!), then check your ISC. Normal idle is 750 +-50rpm.

Beyond that, the standard idle surge checklist is your friend. And yes, get the car running right before you put in DSMLink. That way, any new problems that crop up afterward can be tracked down with a known-good baseline.