I have an 87 GT Convertible with a 5-speed. Whenever I make a U turn or a 90-degree turn at slow speed while in neutral (like into my driveway), the car stalls out. Any ideas on what's causing it?
Also check the connector for the fuel pump behind the rear bumper. I had an issue where my car would stumble on hard turns or certain bumps. Ended up being a bad connection in that connector.
Idle could also be too low. The PS takes a lot of power at full lock and can cause a car to shut off if it's not running right.
I would recommend starting at your battery. Make sure that the hold down is installed so it's not moving around. Check the battery cables and all the connections at the starter solenoid as all your power comes from there. Also check that the computer ground on the fender near the battery is nice and tight.
I checked the battery after having the car sit for a couple of days, and the tester showed that the batter was a bit low. The cables looked secure, as was the battery itself. Since this generally happens with the engine running, I picked up a Ford OBD-I scanner, and ran both the KOEO and KOER tests. Engine off gave me no codes. Engine on gave me code 33, which according to the book that came with the scanner, is an EGR valve fault in that it's not fully opening. Could that be it? Other than that, there are no additional engine computer trouble codes being shown.
It's a stock engine, and according to the guy I bought it from (second owner, who is a mechanic), the only changes made to the car were welded subframe connectors and a 3.73 rear end, so whenever I pop the hood, it's just the same as it was when it was built 34 years ago. I guess that's a testament in and of itself to these cars - take care of them and they'll last.
Another test:
Jack up the front and feel if the front turns freely, test it koeo and koer to see if the rpms still drop.
I'm thinking I know the answer or at least where to look but as usual I can't find that file in my head.
Ha e you noticed whether this problem is more pronounced when the fuel level is low? Does it happen when the tank is full? Or, during spirited driving?
OK, so here goes. I changed the distributor cap, rotor, plugs and wires using the kit from LMR. Changed the starter, too, because that was on it's way out. Had the car out today after a while and noticed a couple of peculiar things. The first: while it was sitting in the garage, the idle would fluctuate between about 700 and 1000 RPM without me even touching the pedal. In fact, I was out of the car when I noticed it. The second: while out driving, when I shift into neutral, I noticed that the RPMs race a little and then drop. It was almost as if it was going to stall, but once I blipped the gas a touch, it would even out. The previous owner said something about he changed the throttle position sensor at one point. Could that be it?
That's what these cars do. Most of us have dealt with this. That's why you have to keep diagnosing the common problems. I changed my Throttle Position Sensor, and it made a difference in idle. I have noticed over time the " hobby " of these cars is working on idle.
The IAC that's on there looks like it's the original. I cleaned the throttle body today and then ran both a KOER and Cylinder Balance Test, too. The KOER gave me an EGR valve code (33), and the Cylinder Balance Test passed (90).
Changed the IAC yesterday and it seems to have solved the surging idle/stalling issue. But, my idle seems to be on the high side now. When I first start up, the engine kicks to 2000 RPM and then drops to about 1100, where it stays. I’ve tried to lower the idle using the set screw, but it doesn’t do anything, either up or down. I’m running a T5 transmission, so from what I’ve read, the idle should be at about 950, give or take.