[Q] How to improve fuel economy in a 88 Mustang LX Conv. and more...

Hello group I have 3 questions for you guys, I would really appreciate your help, thank you very much in advance.

[Q] 1, I am getting barely 22/mpg (around 245 miles per tank). I would like to improve the fuel economy. The factory specs say that the car will do 25/mpg in the city and 30/mpg in the highway. Is there anything I can do to get better mileage than 22/mpg in a 2.3l 'tang? [Q] 2. The smoke coming out of the exaust pipe smells like the air/fulel mix is a little to rich in gas, should I get a new oxigen sensor? [Q] 3. (Forr computer experts) I scanned the computer codes using a small ACTRON/// scanner and it gave me a code 34 which means EGR Valve Position (EVP) sensor or Pressure Feedback EGR (PFE) sensor: signal voltage out of Self-Test specification limits, or, signal voltage above closed limit during normal engine run operation, or,signal indicatesinsufficient EGR flow. Should I get a new EGR valve?

Thanks a bunch again!

Reply to
Pepito
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The fuel mileage specs are not factory specs.... they are assigned by a third party that tests all makes under controlled conditions and assigns the mileage rating. There is no tried and true way to be sure you can meet or exceed these numbers other than watching your driving habits, keeping the tires properly inflated and making sure that the car is in a decent state of tune. These three things have a great impact on fuel mileage and cannot be overlooked if we are on a quest for better mileage.

As far as the exhaust being rich........ I've yet to meet the person that can tell whether the mixture is off with their nose unless the mixture is off grossly. In this case you'd be getting diddly for fuel mileage. Additionally, there are far more things that can drive mixtures lean than those that will drive mixtures rich. Lean mixtures will also deliver poor gas mileage.

I'm going to assume that you have the EGR mounted EVP sensor.... these things are famous for setting false codes. All I can suggest is to clear the code, drive the car and retest.

HTH.

Jim Warman snipped-for-privacy@telusplanet.net

Reply to
Jim Warman

I cleared the code a couple of times, drove the car and retested. I still get the same result, should I get a new EGR valve?

What is the most common problem in an 88 Mustang LX causing to have rich mixture? The injectors? The oxygen sensor?

Reply to
Pepito

I've had the EGR valve stick open on me before, car ran like crap. Take the sensor off the back and see if the diaphragm is all the way down. If not try tapping it lightly with a screw driver to see if it will pop back into place. If that don't work you might need to replace it.

Reply to
Ironrod

If the EGR is sticking open, the car will idle like crap. There may also be a possible problem with the EGRV solenoid.

Without having the tailpipe sniffed with a 4 or 5 gas bench, you don't know if the mixtures are rich...... you desparately need to prove this before you tackle it as a problem. If you have a scan tool capable of monitoring fuel trims and O2 PIDs, check those at idle and let us know. These readings will help a lot with diagnosis IF they are out of spec. If you set out to fix something you can't prove is broken, just what is it you're fixing?

Reply to
Jim Warman

This is my first Mustang so I am trying to figure out why the poor mileage, you could say I am trying to fix that problem.

I would have to take it to a mechanic to get a computer/fuel test. I only have a code scanner for Ford cars (this is my 3erd Ford)

I will try to do what Ironrod recommended me tomorrow. The car sure idles like crap, I had an 84 Ford Tempo (carb 2.3) and that car never ever idled like the Mustang does.

Reply to
Pepito

Jim can you tell me more about the EGR and EGRV solenoid like where threy are located and what they look like. I bought a Chilton Ford Mustang/Capri 79-88 but I can't find anything by looking at their drawings of this valve. Thank you for your help!

Reply to
Pepito

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