"Check Engine" help

[estevaf]

Hello There,

I was wondering if someone could shed some light on this problem.

I was driving my Mustang 95 GT last weekend and, I was returnign from a 60 miles trip, when the Check Engine light started keeping coming on and off .

Then, I noticed that the car behavior was like it was starving and getting not enough fuel at full throttle.

After running about 50 miles in that condition, I stopped by a gas station to pump some gas and... The car did not want to start again!

I tried to start the engine for 30 minutes and, when I was just about to give up and get the Mustang towed, it started (the engine was a bit cooler then).
However, it was not a normal start, I mean, it did not start smoothly, it gasped a lot before running ok. I manage then to drive the car home.

Yesterday, I tried to start the engine again (the Mustang is not my daily driver) and it was again hard to do it.
When it finally started, after some gasps, it ran ok in idle for 10 minutes and even at full throthle it did not gasp at all.

Today, I tried to start it again and I gave up, fearing that I could damage the starter motor.

Well, I have read the EEC memory codes and they look like this:

172 – Heated Oxygen Sensor indicates lean condition, right side.
176 – ditto, left side.
181 – Adaptive Fuel Rich Limit Reach at part throttle, right side.
189 - Adaptive Fuel Rich Limit Reach, left side

Any idea what this could be?
Should I expect the Fuel Pump to be failing soon?

Thanks for reading. Any input will be appreciated.

 

[donkey_punch]

seems like your Oxygen sensors need to be changed.

 

[estevaf]

But the sensor seem to be reading something, right?

It is interesting though that the Engine, when it happens to start, runs OK.

 

[Chythar]

The sensors can return values, but not the proper ones. Basically, if the O2 sensors aren't returning the proper values the computer will be making the wrong corrections to the air/fuel mixture. The car can also run really bad if it's getting too much fuel, as opposed to not getting enough.

When your Mustang ran, did the exhaust smell like gasoline? Did you notice if the engine temperature got really hot? Or was it running cold? Did you notice if your gas mileage suddenly got worse?

 

[estevaf]

Last time it ran the temparature was absolutelly normal.
Interesting that you say that the car may be suffering from excess of gas, because when it first happened on the road, it was like the car was choked.

I could not notice milleage changes because I drive the car very rarelly and almost never in long trips like that sunday.

One curious thing I have noticed the last time it ran, was that the exhausts spitted something that first looked like water but then, when it dried, looked like that green rust of brass or copper. Anyway, I may be seeing thing already

Today I was things about disconnecting the battery cable to reset the PCM.
Could that do any good?

Thanks for the help.

 

[mo_dingo]

Try reseting the computer. Then drive the car for 10 minutes. Then do the KOEO and KOER codes sequence. See if the codes are still there. YOu may get rid of some codes that are dormant from a previous problem.

Your O2 sensors are probably NOT bad. They are telling you that you are not getting enough fuel, or too much air.

My guess is you have a serious vacuum leak, or very little fuel pressure. I would check both, and report back.
Scott

 

[estevaf]

Thanks for the inputs.

I will check again this weekend but it seems that will definetelly need a new fueld pump...

Anyway, what brand would you suggest as a replacement for the 95 GT Fuel Pump?

Is this one a good choice?
http://198.208.187.182/internet/PartImage.jsp?mfgname=ACDELCO&prodlinecd=43&acpartnbr=EP360

(Or should I go with the Original Motorcraft and full stop.)

 

[mo_dingo]

If you are going to keep the motor stock, just get a replacement one. Any will do.

But if you want to get some power to the car, get an aftermarket pump.
Scott

 

[HISSIN50]

half the aftermarket pumps are either Walbros or repackaged Walbros, which is the OEM pump.

for the few dollar difference, i would step up to something slighly larger for the sake of doing so. that is just me. good luck.

 

[estevaf]

Thanks!
Where can I find those pumps on the Internet, pls?

 

[HISSIN50]

Summit racing, Late Model Resto, and about 50 other places. also people get them off ebay. grab a mustang mag and flip through it and check out the ads.

good luck.

 

[95strokerPSU]

Might want to try www.poweredbyford.com That's where I got almost all of my parts including my 155 fuel pump.

As a side note...how much could bad o2 sensors screw up the performance of our cars?

 

[HISSIN50]

As a side note...how much could bad o2 sensors screw up the performance of our cars?

quite a bit. the lambdas are used within ~30-120 seconds after start up (once they light off, at around 600*F) and during operation (their input is ignored at WOT on foxes). if not calibrated or faulty, they can really mess up the A/F trim.