99 Sport 4.0. 175k(ish) miles, uncertain service history.

My daughter's daily driver. Fixed a bunch of minor issues in the last 5 months (See parts below), but it's still having an intermittent issue. Only very occasionally, when she's at a red light/stop sign, when she takes her foot off the brake and tries to accelerate, it stalls. Restarts fine and drives fine. Has no driveability issues...shifts fine (auto trans), no loss of power, etc.

This happened about a month ago. It also had a rough idle/difficult start (cranked a while, sputtered before finally 'catching' and running fine) around the same time. To fix the rough idle/difficult start, replaced the idle air control (NOTE: Used a BWD part from a local auto parts store as we couldn't find MOPAR nearby or in stock for quick shipping on line). Mopar Throttle position sensor, and Mopar MAP Sensor. Now the rough idle is fine (idles at 1100ish on cold start, down to 750 when warm and except for the very occasional stall when starting out, you see no problems), but the Stall when starting from a stop is still there (i.e...that problem didn't change after changing those parts).

I ran a smoke test...no problems at all (no leaks).

No rough/loping idle.

No codes.

So far (as part of maintenance, fixing other issues, etc....we've only had it 5 months, so most are new parts):
(As mentioned above: IAC, MAP and TPS sensors are all new).
Carter Fuel Pump (fixed the check valve issue).
Mopar Crank Position Sensor.
New Battery
New Starter
Greased the Slip Yoke.
Distributor/Cap/Rotor
Wires & Plugs
Coil.

Because it's very intermittent, and no codes, just looking for suggestions. I may wind up springing for the Mopar Idle Air Control, but want to be sure that's still a likely culprit, although as the idle/start is fine (except for the stall), not sure if that could be it as it did it before with the 'bad' IAC and with the new BWD part also.

Thanks for any help.

 

Hmmm. I suppose the IAC is theoretically possible, but I don't think it's a major suspect.

I was going to point a long, bony, accusing finger at the CPS, but you already did that.

Cam sensor is a candidate. It hides in the distributor. If you listen carefully on a warm summer night, you can sometimes hear it chuckle softly to itself, "Heh heh heh. I'm a critical sensor and nobody even knows I'm here!" For some reason, that amuses them no end.

Anyway, if'n I were you I'd get a Bluetooth OBDII reader and hook it up to a phone and log some data. When it stalls, you shold get some useful info out of the logs. I'm partial to OBDLink myself, as they provide good software for Android AND PC. Load it on your laptop and drive around. It will capture more than the Android software.

I tried a generic Bluetooth reader and Torque (freeware), but there was a lot I couild not do with it and there is ZERO support. The so-called "support" forums are a mess. Completely useless.

I think the OBDLink's excellent software for both platforms is worth the money.

 

I may go with the Bluetooth reader (most of my code readers are 'dumb').

I did replace the Distributor (and it came with the pickup/cam position sensor) with a Cardone reman unit...(mostly because when I went to pull the cap off, one of the screws snapped). Certainly a good possibility if the new one is 'off' a bit.

I did keep the old pickup sensor, so maybe I'll swap that back in for a few days and see if it fixes the problem.

Thanks for the tip.