Won't start without starting fluid, then idles at 2,000-2,200 rpm??

Mkviiiswap97gt

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Any update to this thread? I have 97 mustang with a mkviii swap thats only starts up with starting fluid and revs exactly the same, i also noticed if i unplug the iac while the engine is already on with starting fluid the rpm's drop from 2000- to about 600-800 rpm, I noticed that the car will stall out if you press on the accelerator too much while its idling and the iac is unplugged, i was trying to see if the car would be drivable without the iac

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Mkviiiswap97gt

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What trouble shooting steps have you tried?
Well..... Just about everything I have a video of my most recent steps, but back to the begining i could think of i assumed it was my clutch because when it broke down the first time i was barely able to drive it home and I mean BARELY, after the clutch was done i noticed one of the mickey moused vaccum lines was ripped so i replaced the connector and threw some new spark plugs in and it wouldnt start I sprayed some starter fluid after replacing my battery that tested bad but had full charge, Nothing. Then I had a neighbor help me check for spark at the end of the boots, He said nothing happened when I would crank it,So i assumed the coil packs were shot out since they were duralast, I replaced them since almost every sensor in the engine bay is lifetime warranty but no change. He recommended i change the MAF sensor, nothing happened. My gf told me a story on how her 300zx wouldnt start because of an alternator once so i purchased one of those as well ....nothing. Then i decided to get all the free stuff out of the way so I changed the Crank shaft position sensor, Throttle position sensor, and spark plug wires since they all have to do with getting spark and ive had luck with changing them before, And finally booom! All the starter fluid i had tried before backfired and made smoke come out of the intake. I tried to start it up again on its own after and it started up extremely loud for 1st time in like a month but i noticed alot of white smoke coming out of my exhaust, and my idle would not come down from 2k consitenstly and even though it was cold outside that much smoke to me was way too sketch so i shut it off and decided to try again in the morning when it was warm. When the car is started warm it does not smoke but the rpm hang is consistent unless the IAC is unplugged, then it will idle at 6-800 rpm but will stall sometimes if gas is used, if i unplug the MAF while idling the car stalls immediately so that checks out to me all fuses look good too im honestly confused because the car only starts with starting fluid now but it has more than enough gas in the injectors to constantly run at 2k rpm so I highly doubt its a fuel delivery issue?
 

Mkviiiswap97gt

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Check fuel pressure and power to the fuel pump.
Fuel comes out of the shrader valve when pressed and the fuel pump primes when Key On Engine Off, the car also mantains 2000 rpm idle could a bad fuel pump or open circuit cause the fuel pump to constantly send a signal to the pump because if the injector are always reading a pulse it would tell the computer the car was in flood mode wouldnt it?
 

01yellercobra

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Just because it's coming out of the schrader valve it doesn't mean it's making 40psi of pressure. But if it's making enough pressure to keep the engine running at 2k I'd hold off on the pump for now.

Since it drops idle when you unplug the IAC I'd at least say it's suspect. Normally I'd say vacuum leak, but if that was the case it would stay up when you unplugged the IAC. You can try cleaning the IAC to see if anything changes.
 

Mkviiiswap97gt

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Just because it's coming out of the schrader valve it doesn't mean it's making 40psi of pressure. But if it's making enough pressure to keep the engine running at 2k I'd hold off on the pump for now.

Since it drops idle when you unplug the IAC I'd at least say it's suspect. Normally I'd say vacuum leak, but if that was the case it would stay up when you unplugged the IAC. You can try cleaning the IAC to see if anything changes.
I cleaned the IAC yesterday with carb cleaner and a little brush and I even got to the dirtier part of the actual cobra intake with some cutips and a vaccum and i thought it would help with the idle but its still at about 2k maybe slightlier less but no real improvement any other suggestions or tips?
 

01yellercobra

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I'm assuming this is a 4V swap into a GT. What ECU are you using? Did you extend or change any wires?
 

railroad

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Check to make sure your MAF sensor is not mounted 180* off, or better stated as backward.
Probably obvious, but symptoms sound like massive air leak after MAF sensor.
 

Blown38

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There is possibly an air bleed valve on the throttle body. It is located between the 2 bores next to the TP sensor. You will probably need to remove the TB to get to it, if it is straight up Mark 8 stuff with the verticle TB mount. There should be a rubber plug in the hole on top of the valve. I had a buddy's car need this recently. It's a Mark 8 swapped T Bird.
 

Blown38

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Heres a pic of the hole missing the valve. Not sure If I still have the pic of the valve and cap. Ah still have it. You could probably just reach your hand back there and feel around for it.
 

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Mkviiiswap97gt

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Did you check the TPS voltage? - this needs to be in between 0.95-1.0v key on engine off
Check to make sure your MAF sensor is not mounted 180* off, or better stated as backward.
Probably obvious, but symptoms sound like massive air leak after MAF sensor.
^^^Winner goes to you guys for making me question the TPs when i was pointing fingers at random s**t
went a bought a $7 harbor freight dvm and it actually helped, after trying to figure out how the tps worked and i noticed that it was getting 4.63v at all times when KeyOnEngineOff. I attempted to reinstall the tps and was able to make it read 1v once, but as soon as I opened the TB the sensor would read up to at 4.6v at WOT but would not go back down to 1v as if the circuit got jumped. I unplugged the iac to see if it affected the voltage at all and i got nothing, i actually think the iac was working perfectly by trying to suck all that air it thought it was getting through the hose attached to the CAI. The TPS also rattled very noticably when shooken so im sure some resistor or something in there was either defective or i broke it upon installation. installed a new TPS last night, tested for around 1v at idle and gradually goes to about 4.6 when opening the TB. Also very happy at the fact that the car started with no starting fluid or hesitation after replacing the sensor and the engine was idling at 1k rpm on a cold ass night, so im assuming my problem is fixed but Id also like to run every test you guys suggest as im sure my swap is not 100%
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