2000 GT Idle/Running Issues

junkman306

New Member
Sep 22, 2009
19
1
3
Sparta, Mo
www.streettostrip.com
Hi kids. Longtime listener, first time caller. So I bought a 2000 Mustang GT. Auto car. 203xxx miles. The previous owner said it's had the crank sensor, cam sensor, throttle position sensor, fuel pump, fuel filter, battery, brakes, complete stereo system, all of suspension bushings, tie rods, sway bar, rebuilt transmission, injectors, coils, new radiator, condenser, and new head lights in the last year. He said it quit running after his son slid it into a ditch this past winter so they replaced the fuel pump based on a mechanics recommendation. He originally thought that they had pinched a wire when they put the front fender back on and fried the computer. It'll crank and try to start and then backfire and die. He said a code reader wouldn't link to the computer so he was certain it was the computer. He also said that at some point, the connector to the abs pump started smoking so it is currently unplugged.

When I got it home I immediately scanned it with my scanner and it linked to the computer just fine. There are no codes. Here is a video of me trying to start it when I first got it home:

View: https://youtu.be/U02aoQu7UIY



After adding a can of Seafoam, 3 gallons of 91 octane fuel, and about 2 hours of cranking, I made it to here:

View: https://youtu.be/XLk9Owos7s0


View: https://youtu.be/oztQpQkTRmI


I let it idle for probably 30 minutes like this. Still no codes. Then I remembered to do the KOEO and KOER tests with my scanner. KOEO came back fine. KOER shows a P1000 and P1101. Maybe it's the MAF causing this? I did take the cold air intake off and clean the MAF. I also installed a new SPECTRE air filter because the old filter wouldn't clean. It also seems to only idle like the above videos once it has some heat in the motor. At first I thought it had some bad gas in it. Timing is randomly off, maybe? I will add some live data later this week. Here is a pic of the engine as it was when I got the car. It has yellow coils (Accel maybe?) And orange injectors.


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junkman306

New Member
Sep 22, 2009
19
1
3
Sparta, Mo
www.streettostrip.com
So all 8 plugs were NGK TR55s. And they were black. I replaced the #4 coil and all 8 plugs. I also swapped the MAF sensor with a used unit from pick and pull. It still hates anything below 1/2 throttle, but I managed to run it up the highway about 5 miles. It pulls fine at full throttle. Anything under half and it won't stay running. Tps voltage reads .95 with the key on. See pics below of the coil and old plugs. It almost seems like a ground issue. Is there any live data that I can show you guys that might help?
 

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junkman306

New Member
Sep 22, 2009
19
1
3
Sparta, Mo
www.streettostrip.com
This morning I tried to log freeze frame data and it now shows a P1116 on the KOEO test. The temp gauge on the dash always shows half way between cold and hot. The car hasn't been running yet this morning and my scantool shows the ECT is 50 degrees.
 

junkman306

New Member
Sep 22, 2009
19
1
3
Sparta, Mo
www.streettostrip.com
Messing with it this morning reading live data, while it's doing it's usual crappy low idle, calculated load fluctuates between 88% and 92% and the TPS always shows 17.6% at idle. STFT B1S1 is 52.3% and STFT B1S2 is 99.2%. Same percentages for SFST B2S1 and B2S2. P1000 and P1101 are always there on the KOER test. I think it's a wiring issue. I guess I'll dig out my Power Probe.
 

junkman306

New Member
Sep 22, 2009
19
1
3
Sparta, Mo
www.streettostrip.com
I got it to run well enough to take a 17 mile drive last night. It ran crappy, but it ran. When I got back it had a P1151 and a P1131. I didn't mess with it much today, but for the 2nd time starting now, there's been black splatter on my driveway behind the tailpipes. It's oily. The plugs I changed were black and only had 13,000 miles on them. Oil getting past the rings maybe? I had about 30 minutes before work so I checked a few things in general under the hood. I noticed that the elbow from the vent fitting on the drivers side valve cover to the plastic tube was all but dust. It was rotted bad. When taking the tube out of the rotted elbow, the other end that goes into the intake tube just fell of the hose that attaches it to the intake tube. Very loose. So for the time being, I grabbed a zip tie and pulled it as tight as I could. It's now tight enough that it won't even turn in the hose. I put a new elbow on the drivers side at the valve cover. Ill check it Sunday to see if that helped any. There is a vacuum fitting off of the back of the upper intake that goes to a hose that runs down beside the passenger side strut tower. Where does it go? I couldn't see well enough to follow it. That hose is fairly rotted as well.
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