princetomtom

Hey
I'm a noobie. Anyhow, I'm not sure if this is an ok place to post this but...
I am having some trouble driving my car around the city. It is a 1988 Convertible 2.3L EFI Automatic.
Let me start of firstly by saying I can drive across country on the highway with no problem, but give me ten minutes in stop-and-go in the city and my car bogs down, sputters, stalls, etc. Extreme loss of power. Now at night especially when it's cool it drives pretty darned great.
When the engine is warmed up for a while the acceleration gets progressively worse til eventually i cannot even barely increase my speed without throwing it into 2 (car is an AUTOMATIC). It is a COMPLETE nightmare to drive in the summer.
Also to note it takes anywhere from 2-5+ constant cranking then off then crank again then off... just to get it to start. But even then it is known to shut back off then i have to start again and that's when it runs ok for the time being.
Any help would be greatly appreciated.
Thanks

7_Zero

Have you pulled the codes yet? That might help you get a more specific idea of where the problems are. When was the last time the car had a good tuneup? Plugs, wires, distributor cap, rotor, fuel filter, air filter, oil change etc.? That might help with the hard starts.

As for it bogging down during city driving, my bet is that it is an EGR (Exhaust Gas Recirculation) problem. The EGR valve is probably open/closed when it shouldn't be. It might be caused by a dirty valve that is sticking and not closing properly or maybe a faulty EGR valve position sensor sending back a bad reading. You can pull the valve off and try cleaning it, also check to see if the valve is moving properly by applying vacuum to it (or just by sucking on it ).

On mine, it turned out that it wasn't getting any vacuum at all due to a plugged up EGR vacuum control solenoid. After cleaning the solenoid and the valve, it worked a lot better and there was a drop in the frequency and severity of the bogging/stuttering. However, I still get a fault code for the position sensor, so I think that once that is fixed it might eliminate any EGR problems. Not sure though as I haven't gotten that far yet.

A couple of other things to look into are the IAC (Idle Air Control) valve and also the TPS (Throttle Position Sensor). I found that cleaning and adjusting those also helped with some of the problems.

princetomtom

Thanks for responding to my post
Yes I have pulled some codes. I have pulled 32, 72, and 73. Codes 72 and 73 seem to go away once i goose it at 3000 RPM+. I have looked at my IAC and it does not seem to stick. I did lighly swab some of the carbon out of it. I havent done anything to my EGR yet. As for the solenoid I have no idea how to clean that... is it on the passenger side of the engine compartment? Lol. wouldn't sucking on it get that gunk in your mouth if its dirty?

As for the TPS sensor... I took that out a year ago in august and i repositioned it. It wasnt dirty, though I don't know how it could get dirty. Re positioning it made the car run significantly better but the bogging down issue was around at that time as well.

I had my spark plugs and wires replaced about a year and a half ago. Last april I had my car sent to ford for diagnostics, of which they did not do crap to help me out. Only thing they did was adjust my timing, which they claim was off by 12 degrees. Then they charged me $118. Though my car ran smooth like butter after they messed with the timing. About a month and a half down the road the car went back to its normal crappy driving situation.

So does it seem fair to assume the timing could be throwing off and causing issues as well? I have had the car for two years and have never checked to see if the timing belt is going out. Though I would have thought that when ford corrected the timing they would have checked the belt out. But yet again maybe not. Lol

dreamer1uk

Hi,

What year is your Mustang?

Code 32 - EGR valve not opening properly
Code 72 - MAP/MAF BP out of range
Code 73 - TPS Fault.

For code 32, you could use a vacuum gauge and apply vacuum to the EGR valve and see if you can visually see the EGR valve moving.

Code 72, again use the vacuum gauge on the MAP sensor if equiped along with a DVOM on the GND and SGN RTN and see if the voltage changes under vacuum. Also, look at the vacuum line going to the MAP sensor for damage ect. If the vehicle is MAF equiped, check the wiring and the heated wire element for dirt or damage. You can also check those with a DVOM.

Code 73 - I would complete a base idle reset and again, use a DVOM to make sure your TPS reads around 0.98v at idle and 4.9 at WOT. Obviously you will do that test with the KOEO

Hope this helps.

I also forgot to add that when TFI's go bad (model year dependant), it will cause stalling issues.
How the temperature of the vehicle when your driving in city traffic? Does the rad fans come on?

7_Zero

Did you ever get this fixed? I'm wondering if it is more the TPS than the EGR that is causing your problems. Now that it is warming up here, my car started doing exactly as you described. Once it gets hot, the idle gets out of whack, it bogs down and I loose power. I checked my TPS and it read correctly, however I found that if I pushed on it with my finger it would change. I reset the base timing and re-tightened the TPS and so far so good. Since it has been a year since it was last checked, I would suggest you reset it. Stinger has a good right up on how to do this on his website, Stinger-Performance try that and let us know if it helps clear things up some.

As for the EGR and solenoid, the EGR valve is located on the back side of the upper intake, it is to the right of the TPS, there is a pipe that goes from it down to the exhaust. Theoretically all the gunk and buildup should be on the opposite side of the diaphragm so you can suck on the vacuum port without sucking out any garbage. However, if the diaphragm is bad, then something might come through. You just want to make sure that the valve can move freely. To clean it you can use some carb cleaner, just be real careful not to get the cleaner on the diaphragm as it could ruin it. Or you could just use a screw driver or something to chip away at the carbon deposits.

The EGR control solenoid is the one that is on the passenger side. It controls how much, if any, vacuum is sent to the EGR. On mine, I found that the small foam filter on the backside of the solenoid was clogged and caked in dirt. I cleaned that and the tiny hole behind it and got it working again. Just be careful with it as the solenoid and vacuum connections are plastic and can become very brittle after 20+ years in the engine compartment. If you have some tubing and a vacuum gauge you can see if any vacuum is getting to the EGR by running the hose and a gauge inside your car and go for a spin. You should only see vacuum being applied when you are cruising or under light acceleration. If the car is at idle, or you floor it, the valve should be closed and no vacuum present.

If adjusting the timing helped with the problem last time, it wouldn't hurt to check it again to make sure it is still on. $118 is ridiculous, but what can you expect from the dealership? You can pick up a timing light for $20-$30 and check the timing yourself. It is actually not difficult to do.

Dreamer has some really good info in his post too, try some of these things out and keep us updated.