PATS gremlin while driving??

[funinak]

While driving down the road at different speeds, gears, conditions the PATS light will come on steadily and the car will loose all power momentarily. Sometimes it happens for just a second or recently has lasted for a few seconds. The light goes off and then the car comes back to life???? This has happened randomly over the past couple weeks. The car has never done it before in the 1 1/2 years we've owned it. What could be the cause of this happening? :shrug:

 

[BrApple]

well it was my understanding that PATs only checks the key on startup. I have first hand experience with this when I used the ignition out of my 95 in my 99 and only held the key to the antenna while starting the car.

do you have a chip installed? if so that could be having a connection problem. If so make sure it doesn't come out with the key in the ignition as it will erease the key info in the pcm.

otherwise check your ground and the electrical system.

 

[iBrent]

The same thing happened to me. A few times on the interestate. It sucks when your car dies at 70mph in the fast lane.

I would pull over, and wiggle the battery, which usually allowed it to restart. I found out it was the negative battery terminal. The crimp connections that terminated the black wires to the little loops that go over the battery terminals were extremely loose. In fact, I was able to pull one out of its crimp connector without little effort. I bought some new terminal connectors, re-crimped them, and all was fine.

 

[Ray]

This is a VERY troubling problem to track down.


Know this though:

the PATS is not involved WHATSOEVER once the car is started. Your PATS light is flickering BECAUSE it is regaining power.

I've got a very well documented list of symptoms you are likely experiencing Let me see if I can find mine.

brb

 

[Ray]

here the MY particular post.. but you will find three or four threads with IDENTICAL situations..

such as THIS ONE

I just fixed this problem on my car.. lasted (PLAUGED) me about 8 months. Started out being once or maybe twice a week... then a day.. then every two or three minutes. Eventually I could even MOVE the car because it happened every second, twice or three times a second.

My symptoms:

* CEL light would "flicker", or sometimes STROBE very rapidly.
* PATS light would illuminate and do a 1 second "prove out" test, as if you just turned on the ignition.
* tach would drop/dive towards 0
* car power wasn't affected.. radio, lights, etc, remain
* fuel and spark were GONE during that time. no acceleration, no idling (when it got worse, that is).. nothing..
* voltage at the BATTERY wouldn't move.. would drop from 14.2 to 13.7-ish but that was only because the engine wasn't turning over any more and the alternator stopped producing power, for a second..


I checked everything. PCM power.. battery power.. IGNITON ITSELF (jumpered around the ignition to prove it wasn't the problem)
searched for loose grounds.. everything

The problem? a bad TPS wiring connection.

The TPS was fine.. the WIRING harness to the TPS was shorted, from the positive supply to the ground, which is a shared supply for a lot of the rest of the wiring harness, including the gauge cluster, the ignition, and the pats power.

Never in a million years would ANYONE that I told, or asked help from (on CEG, etc) have imagined that something related to the TPS would cause such EXTREME symptoms.

What should you do?

Check ALL of your grounds in the engine bay.

under the battery/fuse box
at the firewall on the passenger/center side, everywhere.
check the negative wires that go to the battery, and make sure they aren't loose in the crimped on ring that attaches to the battery.

then... the next time it is doing this, repetitively (if it gets worse and more frequent), unplug the TPS from the throttle body.. I bet it smoothes out and stops.