2001 Grand Cherokee stalling

I have a 2001 Grand Cherokee 4.0L with 215xxx miles. It just started stalling coming up to a stop, but then it starts right up noproblem. Engine idles a little rough and trhe gas milage has gone down somewhat. The CEL came on a while ago, and the auto shop checked the computer code and said it was the neutral safety switch. I brought this up with a friend who had the same problem and he rebuilt his and said it was easy. So I was going to attempt it, but I can’t find the darn thing. @ questions: 1)where is it? and 2)could the NSS be causing the stalling?

Thanks.

The NSS will not cause stalling.

I agree with PvtPublic. Additionally, it won’t trip the CEL. Are you sure about the code? A faulty throttle position sensor or idle air controller (or the associated wiring) are more likely to be the culprit(s).

Jeeps do put the light on for transmission range sensor, its on the passenger side of the trans, just follow the wires.

Throttle position sensor or vacuum leak is more likely for a stalling problem.

Jeeps do put the light on for transmission range sensor, its on the passenger side of the trans, just follow the wires.

I wouldn’t have thought so in a 2001. I learn something new every day here?

I’m going to guess that the code was in the P070x range (transmission range sensor circuit…). But @brewchemist if you report the specific code that might help people respond.

Also note that a problem here is NOT likely to explain your symptoms. Even so, if you do have a P070x code does need to be addressed. But the code doe NOT point to the switch itself. Those are all codes for the circuit. The switch is only one part of the circuit. It is normally attached to the other end of the shifter mechanism. Eyeball the top of the transmission, and ask someone to get in the car and move the shifter between various positions. Look for what moves. Then investigate a problem with the whole circuit.

Thanks for everyones comments. I did the trick of turning the ignition on and off 3 times to trigger codes, and it displayed 3 of them. Unfortunately I left them at home, but I will post them later. Again, I appreciate any help.

Ok, here we go. The codes are: P0320, P1899 and P0456.

Again any help is appreciated.

In reverse order, the codes are:

http://www.obd-codes.com/p0456. Small leak in evaporative emissions system. Could be leaking gas cap, leaking filler neck, leaking charcoal canister, leaking purge/vent valve, or leaking hose.

P1899: neutral safety switch stuck in park or in gear.

P0320 Ignition/Distributor Engine Speed Input Circuit Malfunction

I don’t know the specifics of the ignition or timing control on this vehicle, but your symptoms are most like going to be from the P0320. It’s probably a crank position sensor. The PRNDL / neutral safety switch is not likely to cause those symptoms. However, when you do get around to that, this might be useful: http://www.bc4x4.com/tech/2010/jeep-neutral-safety-switch-nss/

One thing to think about though is whether or not you have some damaged wiring harness that might be affecting both things. Recall that most of these codes are circuit codes - not “part” codes. The PCM/ECU only has access to what “parts” are doing via their circuits.

Thanks for all the information, I really appreciate it. I will get to everything when time allows.

The NSS would cause the engine to not crank, or fail to crank intermittently. It wouldn’t affect the idle quality or speed. The evap problem may or may not affect idle speed or quality. Depends what the problem is. The engine speed (rpm) problem could cause all sorts of drivability, idle, and fail to start problems. You’re going to have to fix all of them to get the vehicle back to it’s former reliable state I think. It’s hard to say which is the one to fix first. I guess since the NSS can make the engine impossible to start – and since if it won’t start it doesn’t matter whether it idles well or not – I’d probably start with that one.