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Discussion Starter #1
Hey all,

I have a 1987. With the spout connector off, it idles great, with the spout connector on it doesnt idle, doesnt want to start, and missfires bad.

I am assuming that with the spout on, the computer adjusts fuel, and with it off, fuel goes off a base map.

The ECU is making the car really rich with the spout on, which means there is something wrong somewhere.

I need to check the TPS, EVP, and MAP sensor (which are all new anyways), but I think the reason is I dont have a midpipe installed, so the 02 sensors are just reading atmosphere air instead of exhaust air. That would cause the computer to go super rich right?

I tried pulling the codes yesterday, but nothing was pulling up, so thats a different problem.
 

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With the SPOUT out, timing is whatever it was set to. Factory is 10*. Remove the SPOUT and the engine will run at 10*. With the SPOUT in, the computer takes over, and will adjust timing based on load, ACT and ECT temps, TPS, MAP, and the O2 sensors. timing can run as high as 20* or so IIRC. To shorten the list of possibilites, replace the missing exhaust. IF the O2 sensors are reading mostly air (for any reason), the computer will add fuel to compensate.

As for the SPOUT itself, check your timing. Make sure the balancer has not slipped, which will screw the timing. If that checks out, has the distributor been pulled recently? If not, you may have a short to ground in the SPOUT connector, or wiring back to the computer. Or a failed TFI.

You said no codes, but see post #2 here anyway.

https://www.stangnet.com/mustang-forums/threads/what-causes-no-advance.788697/
 

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He's right, the spout only interupts the computer control of the timing. The computer has no idea if spout is in or out. So your conjecture isn't correct. If you can't pull codes check tps voltage at green wire, if it is 4.9v your sensor return is fried. If it is .98 or thereabouts, then computer should generate codes.
 

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Discussion Starter #4
Thanks for the help guys, I tried puling codes again yesterday and it worked.

I got codes 34, 67, 81, 82, 85.

I deleted all the emissions stuff minus the egr and egr solenoid.
 

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Google those codes and post them up.
 

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Discussion Starter #6
34 - EGR Valve Position/Pressure Feedback EGR Voltage Above Closed Limit (O,R), PFE or EVP circuit has intermittently failed above the closed limit of 0.67 volts (CM)
67 - Park Neutral Position Switch Circuit Open; A/C On -Manual (O), Manual Lever Position Sensor Out Of Range/A/C On (CM,O), Clutch Switch Circuit Failure (CM)
81 - Secondary Air Diverter Circuit Failure (O)
82 - Secondary Air Bypass Circuit Failure (O)
85 - CANP Circuit Failure (O)

I dont have any emissions stuff except for the egr and the egr solenoid. I also dont have the canister purge solenoid.
 

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Ok, so they are normal then. You need a chip to turn them off. Your issue seems to be that the timing is way off. Disconnect spout and set your timing to 12 or so. Don't try that 'timing by ear' bs, it doesn't work. Mark your balancer so you can see the marks clearly with the timing light. Then check for vacuum leaks, unplug O2 sensors and see if that improves it. Also makes sure large black wire for computer ground goes to battery negative terminal.
 
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