Mechanics

RUNS ROUGH THEN STALLS

1998 Lincoln Continental

Computer problem
1998 Lincoln Continental V8 Front Wheel Drive Automatic 91000 miles

Hello,

A few months ago my Continental would not start out of the blue. It would start and run rough briefly but it would not respond to giving it gas and would soon die. I discovered it would start while holding the accelerator to the floor and run fine after. Recently it started to lose power with the same symptoms while driving and eventually stall out with the " service engine" light on. Same thing; turn key off and restart w/ pedal to the floor and it runs fine for a while, light goes out. Happened 3 times on a recent 750 mile trip. So hot-cold-driving-not driving doesn't appear to make a difference.

The OBD II scanner pulled not one code. I was thinking it may be the TPS with the conditions I described above, but wouldn't that set a code?

Any input is appreciated.

Thank you
Avatar
Fredrok
July 1, 2010.



Hi fredrok, Welcome to 2carpros and TY for the donation.

Lets do this check and test the TPS closed idle and wide open throttle voltages and clean the MAF sensor with an approved cleaner and see what happens-also test the coolant temperature sensor

Rasmataz
Jul 1, 2010.
Thank you Ras. I cleaned the MAF and the ACT sensor that was just downstream. The MAF was hard to tell but the ACT was filthy. I can only imagine the same with the MAF probes. I'll read TPS voltages and with the coolant temp sensor, do you mean just take ohm readings cold and hot?

Thanks a bunch.

Tiny
Fredrok
Jul 2, 2010.
CTS

The normal resistance on an engine with 50 to 80 degrees F = 2,200 to 2,700 ohms. As the sensor temperature DECREASES, the resistance value will INCREASE.

Rasmataz
Jul 2, 2010.
Thank you Ras. It's been a while. But I wanted to get some miles on it since it's infrequent. I ended up just replacing the TPS and CTS shortly after I cleaned the MAF sensor.

I drove it a couple hundred miles w no issues and sold it to a buddy. He got 400 miles down the road to go home and it did it again but was able to get to the next auto parts store and pull a code: P1152. It stated bank 2, O2 sensor 1 rich and that it could be caused by fuel pressure issue or stuck EGR valve. It started running okay as before, but he states a bit sluggish now. He reports that it was bucking and he could smell " exhaust" more and the check engine light came on. Happened a couple more random times, each one wait a few minutes-start-and go for a long while.

Given it's infrequency and suddenness when it does happen, could it be the EGR valve? Maybe still the MAF? It didn't die on him completely this time, but when it did w/ me, I had to hold the acc. To the floor to get it running.

Suggestions please!

Thanks!
Fred

Tiny
Fredrok
Aug 20, 2010.
Rescanned the computer again

Start the car up and let it idle then tap on the MAF sensor-it shoudn't react, if it does there's still a problem with it. Also test the TPS and MAP sensors to include cleaning out the EGR valve

Rasmataz
Aug 20, 2010.
Thank you Ras. I'll follow up. I've replaced the TPS and will check the rest. We may even replace the EGR valve all together if the rest checks out. Oddly, it seems to be fine around town but is doing it every 15 mins. Or so on the highway now after the first 400 miles.

Thanks for your help

Tiny
Fredrok
Aug 20, 2010.