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Discussion Starter #1
OK so i have an 88 mustang gt and i replaced the lower intake and marked the distributor and everything but when i put it back in it ran kind of rough it would full on its face and backfire when i gave it quite a bit of throttle so i took it to a buddy who is a mechanic(GM may i add) who had a timing light and he told me to line it up with the hole tab on the crank and not the pointer so we did and i took it for a spin and it seemed fine but after driving it around further i found it didnt have as much power as before replacing the intake and removing the distributor and had a faint smell of gas from the exhaust. also i was not sure exactly where all the vac lines went such as the map sensor egr valve(this vac is going to the left i am pretty sure it is in the right spot) and fuel pressure regulator and other vac lines under the upper intake two plastic ones which were broken off from before. so my question is should i time it to the pointer and not the hole or could it be a vac leak or wrong vac lines hooked up??
 

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I kinda have the same question as you. Because I really don't know either. I timed mine by the pointer and I think that is correct. My car runs fine.
 

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Time it to the pointer.12-14° BTDC with the SPOUT out. Then put the SPOUT back in. This is funny because I have a friend that owns a mustang but works at a CHevy dealer. And he asked me the same thing about the pointer and Hole.

MAP sensor should have its own vac line( not shared with any other vac controlled sensor or valve)should go striaght to the manifold, Egr vac should go to the EGR vac solenoid, and the FPR needs a vac line off the manifold. If I missed something just ask.
 

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Find the marks on the crank pully, clean off the rust, and then mark the TDC line. Remove the spout connector, a small grey connector about 4 inches from the ignition module conector, and set the timing to spec. Once the timing is set, then you can start to check out vac lines and routing.
 

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A little side note, do not start the engine with a remote starter button when setting the timing. The ECM will hold the timing retarded, and your setting will be off.
 

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Discussion Starter #6

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How does the remote starter throw the timing setting off?

This is new to me. A remote starter starts the car the same way the switch does. The SPOUT signal is ignored by the TFI and this is the reason for the tming retard. The ECM is still sending the signal for timing advance, but once start voltage is present at the TFI the advance is ignored SPOUT in or OUT.
 

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Yellow to MAP sensor. The reason its open on the pic, is probably since whoever did the daigram has a MASS air car. ANd its not used on a Mass Air car. Your car should be Speed density, unless its been converted to Mass Air.
 

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Discussion Starter #9
ok i screwed up. again referring to the picture the blue hose going to the lower intake i have where the green hose is which should be going to the tree on the firewall and vice versa. am i in trouble? did i F up my motor? other than that everything is right.
 

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Your fine, But if it bothers you, you can switch it. Mine is the same way on my Cobra Intake. I didnt like the ugly blue line(in the PIC) being so visible.
 

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Discussion Starter #11
alright well i appreciate it guys and i will set the timing to the pointer and switch my vac lines and will let you know how it turns out. this site is frickin awesome it has been a huge help with all of my problems. thanks again!!!
 

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Discussion Starter #12
ok so my vac lines are switched and i talked to the guy that set my timing the first time and he told me that it should be set at 0*so that is what it is set at but not on the pointer i think but i could swear i read on here that it is supposed to be set at 10* what is your guys' input? stupid GM guys always think GM is the best and always say well GM is this and that so....the dude i know wouldnt even listen to me and kept saying i was wrong
 

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If you disconnected the input to the starter solenoid and then used a remote starter, the ecm never recieves a start signal. After running for awhile, or being put in gear, the ecm knows it has started. It was a programing glitch from 86-92
 

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If you disconnected the input to the starter solenoid and then used a remote starter, the ecm never recieves a start signal. After running for awhile, or being put in gear, the ecm knows it has started. It was a programing glitch from 86-92
:nono:This is full of miss information........The only thing affected by start voltage is the TFI. Thats where the retard gets done at. And its only done when start voltage is present. Why is it done? Because once start voltage is present at the TFI, it bypasses the SPOUT signal and its at what ever the base timing is set at.

The ECM it self is not concerned with start voltage. Once the ECM receives a PIP signal, the ECM knows its running. If the ECM didnt know it was running there would be no advancemnet of timing or injector firing.

Where is this info your getting from? I want you to post it up so I can read it.

And tell me What PIN on the ECM is for start voltage.
 

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That little tidbit came from the instructor at Ford's tech center. Out of curiosity I tried it and it does hold true.
 

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So your saying, if I use the remote starter, and then check the timing, with the Spout in, it will be reading what base timing is?

The ecm doesn't see start voltage. It constantly sending the advancement for the timing as long as a PIP signal is present. As long as a PIP signal is present, the ecm knows its running. Why else would a PIP signal be present if it wasn't running? Just ask Joel5.0, I just had a talk with him about this thread. We both have come to the same conclusion. Its BS
 

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The tfi module pin 4 reads start comand. Depending on application pin 5 on eecIV is start, cid, or idm. The tfi module retards timing to allow easier starts, and when the start signal is removed, allows timing adjustment via the spout signal. Is this on all Fords, I don't know, but if it affects one vehicle, the engineers will have you follow the same procedure on all vehicles just to standardize procedures. I tried it again today on my boss's 86 F-150, 300 6 cyl. timing at start 2degrees, running spout out 14(should reset that), and 24 with spout connected at idle. Starting with a starter button (not a remote starter, this may be where we are getting confused, a remote car starter uses the same line to the solenoid and provides start signal to the tfi and ecm) the timing stayed at 2 degrees untill rpm was raised above 1200. Acording to Mitchell, this is the push start mode of the TFI.
 

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There is no start signal going to the ECM, pin 5 at the ECM is not used other than for the TSS or BOO signals in some applications and pin 4 is the standardized position for the Ignition Diagnostic Monitor (IDM) signal, which is the coil collapsing pulse.
 

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On mustangs, pin 5 is kind of like fords mod pin, whatever the engineers want, they put there. 2.3 is start signal, 2.5 is idm, all truck engines are blank, Tempos are auto trans switch. 2.3 dis is cid.
 
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