Engine Car in limp mode, fuel spitting out of tailpipes, missing rough idle


Jun 12, 2017
I was driving my car and it all of a sudden seemed to go into limp mode. The idle is rough, the car is misting fuel out of the tailpipes and every other exhaust connection and is emitting white smoke from the tailpipes probably from burning fuel.

I pulled the codes but was told with a Quarter Horse tune / chip it may prevent the computer from communicating correctly and dumping correct codes. The code I got was 15. The ECU board where the Quarter Horse tune was dark so I thought the ECU was fried. I tested a second ECU I have with the Quarter Horse chip in it and the car ran the same. Any ideas?


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Advanced Member
Jan 10, 2019
White smoke is generally an indication of burning coolant. Did you look inside the radiator? I suspect a blown head gasket. What were you doing just prior?


Active Member
Apr 4, 2007
White smoke is generally an indication of burning coolant. Did you look inside the radiator? I suspect a blown head gasket. What were you doing just prior?
Literally just slow stop and go traffic temp got up to halfway but that it.

I didnt check the coolant, i checked the oil but it looked fine. I'll check the coolant today.


Jun 12, 2017
What is the set up on the car?
With the chip I figure it ain't stock.
Fordstrokers 347:
347 Dart Liberator Complete Shortblock
Dart SHP Machined Block
RPM 4340 Forged Steel 3.400 Crankshaft
RPM 4340 Forged Steel H Beam Connecting Rods 5.400
With ARP 2000 Rod Bolts
Wiseco 2618 Forged Pistons (20cc, TFS) 4.030
Wiseco GFX Ring Package
Clevite 77 H Main Bearings
Clevite 77 H Rod Bearings
Dart Coated Cam Bearings
Screw in Oil Galley Plugs
Fel Pro Rear Main Seal
ARP Main Studs
Freeze Plugs
FordStrokers Custom HYD Roller Billet Camshaft
ARP Cam Bolt
Cam Retainer Plate
SA Gear Billet Timing Chain w/Torrington Bearing
Melling Oil Pump M68HV
ARP Oil Pump Bolts
Moroso Oil Pump Pick up - 24516
ARP Billet Oil Pumpshaft
Fel Pro 1 Piece Pan Gasket
Moroso 7qt Oil Pan - 20511
Mr. Gasket Oil Pan Bolts
- Oil Drain Back, Passengers Side
- 3/8" NPT x 1/2" Straight Hose Barb
Timing Chain Cover - Fox Body
Fel Pro Timing Chain Gasket Set
Trick Flow Twisted Wedge 190 11R Cylinder Heads 56cc = 9.3:1
Morel Hyd Roller Link Bar Lifters 5323
4130 Chromemoly .080 Wall 1 Piece Formed End Pushrods
Trick Flow Roller Rocker Arms 1.6 7/16th
Fel Pro MLS 1133 Head Gaskets
ARP 1/2" Head Studs

Vortech S Trim 11lbs
Holley Systemax Intake
3 core Radiator
Strock Fan
Moates Quarter Horse Chip and Dyno Tune

Easier just to copy the invoice items and post then to sift through and delete the irrelevant items...

I was hoping the Quarter Horse chip took a dump on me...


Active Member
Apr 4, 2007
Ok so... I pulled KOEO codes and got 85 and 15. Great! Bad ECU right? Not so fast!

I pulled the ECU out and swapped it with a spare I have. I only did KOEO and only got code 85. I put the Quarter Horse chip in the second ECU and the car ran the same. I pulled KOEO codes with the chip in and it threw code 85, not 15. I did the KOEO codes again and got 85 and 15!

I'm not sure if the Quarter Horse chip is married to one specific ECU which would not allow it to run with the new ECU. I was told the Quarter Horse chip can prevent the ECU from throwing codes.

I pulled the ECU out and dropped it off to have the Quarter Horse chip checked the make sure it isnt bad.

Now, without the ECU in, I cycled the ignition to the on position several times and left it for about 15 mins while I pushed the car into the garage to make sure the steering column didn't lock.

4 hours later, I came out and there is fuel leaking from every joint on the passenger side exhaust. Maybe 1 drop on the drivers side hanging, not enough to drop to the ground

All drivers side plugs are dry.

Passenger side plugs, #4 soaked with fuel, #3 about half wet, #2 maybe a couple drops and #1 is dry. All 8 plugs look the same other then the fuel.

The injectors are Deka 60#ers.

I have been having an unknown fuel pressure issue to. Fuel would come out of the cap. Ive checked the return line around the tank and don't see any visual pinches or kinks. Ive drilled the cap but it hasn't really helped. It causes crap to stick to the paint around the fuel door as you can see in the picture.

The car doesnt have the smog stuff so I don't know if it does or doesn't have the purge solenoid and I'm not too sure where to find it. I know it doesn't have the canister.

Once I get the car back together so I can crank it (starter nose casting also broke off in the bellhousing last week), i was thinking of starting with a noid light test for the injector harness.

Maybe a bad PIP could cause this?



Active Member
Apr 4, 2007
Same issue related to another thread I started. It was a bad regulator. Original Ford piece, 27 years old.
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